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Sample records for brain reward function

  1. Effects of anabolic-androgens on brain reward function

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    Emanuela eMhillaj

    2015-08-01

    Full Text Available Androgens are mainly prescribed to treat several diseases caused by testosterone deficiency. However, athletes try to promote muscle growth by manipulating testosterone levels or assuming the so called androgen anabolic steroids (AAS. These substances were originally synthesized to obtain anabolic effects greater than testosterone. Although AAS are rarely prescribed compared to testosterone, the off-label utilization is very wide. Furthermore, combination of different steroids, and doses largely higher than those used in therapy are common. Symptoms of the chronic use of supra-therapeutic doses of AAS include anxiety, depression, aggression, paranoia, distractibility, confusion, amnesia. Interestingly, some studies have shown that AAS elicited electroencephalographic changes similar to those observed with amphetamine abuse. Among the AAS abusers, the frequency of side effects is higher, with psychiatric complications such as labile mood, lack of impulse control and high violence. On the other hand, AAS addiction studies are complex because the collection of data is very difficult due to reticent subjects and can be biased by many variables, including physical exercise, that alter the reward system. Moreover, it has been reported that AAS may imbalance neurotransmitter systems involved in reward process, leading to an increased sensitivity toward opioid narcotics and central stimulants. The aim of this review is to discuss what is present in literature in regard to steroid abuse and alteration of reward system in preclinical and clinical studies.

  2. Obesity is marked by distinct functional connectivity in brain networks involved in food reward and salience.

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    Wijngaarden, M A; Veer, I M; Rombouts, S A R B; van Buchem, M A; Willems van Dijk, K; Pijl, H; van der Grond, J

    2015-01-01

    We hypothesized that brain circuits involved in reward and salience respond differently to fasting in obese versus lean individuals. We compared functional connectivity networks related to food reward and saliency after an overnight fast (baseline) and after a prolonged fast of 48 h in lean versus obese subjects. We included 13 obese (2 males, 11 females, BMI 35.4 ± 1.2 kg/m(2), age 31 ± 3 years) and 11 lean subjects (2 males, 9 females, BMI 23.2 ± 0.5 kg/m(2), age 28 ± 3 years). Resting-state functional magnetic resonance imaging scans were made after an overnight fast (baseline) and after a prolonged 48 h fast. Functional connectivity of the amygdala, hypothalamus and posterior cingulate cortex (default-mode) networks was assessed using seed-based correlations. At baseline, we found a stronger connectivity between hypothalamus and left insula in the obese subjects. This effect diminished upon the prolonged fast. After prolonged fasting, connectivity of the hypothalamus with the dorsal anterior cingulate cortex (dACC) increased in lean subjects and decreased in obese subjects. Amygdala connectivity with the ventromedial prefrontal cortex was stronger in lean subjects at baseline, which did not change upon the prolonged fast. No differences in posterior cingulate cortex connectivity were observed. In conclusion, obesity is marked by alterations in functional connectivity networks involved in food reward and salience. Prolonged fasting differentially affected hypothalamic connections with the dACC and the insula between obese and lean subjects. Our data support the idea that food reward and nutrient deprivation are differently perceived and/or processed in obesity.

  3. Brain Reward Circuits in Morphine Addiction

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    Kim, Juhwan; Ham, Suji; Hong, Heeok; Moon, Changjong; Im, Heh-In

    2016-01-01

    Morphine is the most potent analgesic for chronic pain, but its clinical use has been limited by the opiate’s innate tendency to produce tolerance, severe withdrawal symptoms and rewarding properties with a high risk of relapse. To understand the addictive properties of morphine, past studies have focused on relevant molecular and cellular changes in the brain, highlighting the functional roles of reward-related brain regions. Given the accumulated findings, a recent, emerging trend in morphine research is that of examining the dynamics of neuronal interactions in brain reward circuits under the influence of morphine action. In this review, we highlight recent findings on the roles of several reward circuits involved in morphine addiction based on pharmacological, molecular and physiological evidences. PMID:27506251

  4. Brain's reward circuits mediate itch relief. a functional MRI study of active scratching.

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    Alexandru D P Papoiu

    Full Text Available Previous brain imaging studies investigating the brain processing of scratching used an exogenous intervention mimicking scratching, performed not by the subjects themselves, but delivered by an investigator. In real life, scratching is a conscious, voluntary, controlled motor response to itching, which is directed to the perceived site of distress. In this study we aimed to visualize in real-time by brain imaging the core mechanisms of the itch-scratch cycle when scratching was performed by subjects themselves. Secondly, we aimed to assess the correlations between brain patterns of activation and psychophysical ratings of itch relief or pleasurability of scratching. We also compared the patterns of brain activity evoked by self-scratching vs. passive scratching. We used a robust tridimensional Arterial Spin Labeling fMRI technique that is less sensitive to motion artifacts: 3D gradient echo and spin echo (GRASE--Propeller. Active scratching was accompanied by a higher pleasurability and induced a more pronounced deactivation of the anterior cingulate cortex and insula, in comparison with passive scratching. A significant involvement of the reward system including the ventral tegmentum of the midbrain, coupled with a mechanism deactivating the periaqueductal gray matter (PAG, suggests that itch modulation operates in reverse to the mechanism known to suppress pain. Our findings not only confirm a role for the central networks processing reward in the pleasurable aspects of scratching, but also suggest they play a role in mediating itch relief.

  5. Effect of brain structure and function on reward anticipation in children and adults with attention deficit hyperactivity disorder combined subtype.

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    Kappel, Viola; Lorenz, Robert C; Streifling, Martina; Renneberg, Babette; Lehmkuhl, Ulrike; Ströhle, Andreas; Salbach-Andrae, Harriet; Beck, Anne

    2015-07-01

    Attention deficit hyperactivity disorder (ADHD) is associated with decreased ventral-striatal responsiveness during reward anticipation. However, previous research mostly focused on adults with heterogeneous ADHD subtype and divers drug treatment status while studies in children with ADHD are sparse. Moreover, it remains unclear to what degree ADHD is characterized by a delay of normal brain structure or function maturation. We therefore attempt to determine whether results from structural and functional magnetic resonance imaging (fMRI) are associated with childhood and adult ADHD combined subtype (ADHD-CT). This study used fMRI to compare VS structure and function of 30 participants with ADHD-CT (16 adults, 14 children) and 30 controls (20 adults, 10 children), using a monetary incentive delay task. Joint analyses of structural and functional imaging data were conducted with Biological Parametric Mapping. Reward anticipation elicited decreased ventral-striatal responsiveness in adults but not in children with ADHD-CT. Children and adults with ADHD showed reduced ventral-striatal volume. Taking these gray matter differences into account, the results remained the same. These results suggest that decreased ventral-striatal responsiveness during reward anticipation is present in adults but not in children with ADHD-CT, irrespective of structural characteristics. The question arises whether ventral-striatal hypoactivity is an ADHD correlate that develops during the course of illness.

  6. Positive emotions and brain reward circuits in chronic pain.

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    Navratilova, Edita; Morimura, Kozo; Xie, Jennifer Y; Atcherley, Christopher W; Ossipov, Michael H; Porreca, Frank

    2016-06-01

    Chronic pain is an important public health problem that negatively impacts the quality of life of affected individuals and exacts enormous socioeconomic costs. Chronic pain is often accompanied by comorbid emotional disorders including anxiety, depression, and possibly anhedonia. The neural circuits underlying the intersection of pain and pleasure are not well understood. We summarize recent human and animal investigations and demonstrate that aversive aspects of pain are encoded in brain regions overlapping with areas processing reward and motivation. We highlight findings revealing anatomical and functional alterations of reward/motivation circuits in chronic pain. Finally, we review supporting evidence for the concept that pain relief is rewarding and activates brain reward/motivation circuits. Adaptations in brain reward circuits may be fundamental to the pathology of chronic pain. Knowledge of brain reward processing in the context of pain could lead to the development of new therapeutics for the treatment of emotional aspects of pain and comorbid conditions.

  7. Functional connectivity in cortico-subcortical brain networks underlying reward processing in attention-deficit/hyperactivity disorder

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    Marianne Oldehinkel

    2016-01-01

    Conclusions: The present study does not corroborate previous childhood evidence for functional connectivity alterations between key reward processing regions in adolescents and young adults with ADHD. Our findings could point to developmental normalization or indicate that reward-processing deficits result from functional connectivity alterations in general task-related networks.

  8. NMDA receptors regulate nicotine-enhanced brain reward function and intravenous nicotine self-administration: role of the ventral tegmental area and central nucleus of the amygdala.

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    Kenny, Paul J; Chartoff, Elena; Roberto, Marisa; Carlezon, William A; Markou, Athina

    2009-01-01

    Nicotine is considered an important component of tobacco responsible for the smoking habit in humans. Nicotine increases glutamate-mediated transmission throughout brain reward circuitries. This action of nicotine could potentially contribute to its intrinsic rewarding and reward-enhancing properties, which motivate consumption of the drug. Here we show that the competitive N-methyl-D-aspartate (NMDA) receptor antagonist LY235959 (0.5-2.5 mg per kg) abolished nicotine-enhanced brain reward function, reflected in blockade of the lowering of intracranial self-stimulation (ICSS) thresholds usually observed after experimenter-administered (0.25 mg per kg) or intravenously self-administered (0.03 mg per kg per infusion) nicotine injections. The highest LY235959 dose (5 mg per kg) tested reversed the hedonic valence of nicotine from positive to negative, reflected in nicotine-induced elevations of ICSS thresholds. LY235959 doses that reversed nicotine-induced lowering of ICSS thresholds also markedly decreased nicotine self-administration without altering responding for food reinforcement, whereas the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor antagonist NBQX had no effects on nicotine intake. In addition, nicotine self-administration upregulated NMDA receptor subunit expression in the central nucleus of the amygdala (CeA) and ventral tegmental area (VTA), suggesting important interactions between nicotine and the NMDA receptor. Furthermore, nicotine (1 microM) increased NMDA receptor-mediated excitatory postsynaptic currents in rat CeA slices, similar to its previously described effects in the VTA. Finally, infusion of LY235959 (0.1-10 ng per side) into the CeA or VTA decreased nicotine self-administration. Taken together, these data suggest that NMDA receptors, including those in the CeA and VTA, gate the magnitude and valence of the effects of nicotine on brain reward systems, thereby regulating motivation to consume the drug.

  9. Pharmacological differentiation of opioid receptor antagonists by molecular and functional imaging of target occupancy and food reward-related brain activation in humans.

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    Rabiner, E A; Beaver, J; Makwana, A; Searle, G; Long, C; Nathan, P J; Newbould, R D; Howard, J; Miller, S R; Bush, M A; Hill, S; Reiley, R; Passchier, J; Gunn, R N; Matthews, P M; Bullmore, E T

    2011-08-01

    Opioid neurotransmission has a key role in mediating reward-related behaviours. Opioid receptor (OR) antagonists, such as naltrexone (NTX), can attenuate the behaviour-reinforcing effects of primary (food) and secondary rewards. GSK1521498 is a novel OR ligand, which behaves as an inverse agonist at the μ-OR sub-type. In a sample of healthy volunteers, we used [(11)C]-carfentanil positron emission tomography to measure the OR occupancy and functional magnetic resonance imaging (fMRI) to measure activation of brain reward centres by palatable food stimuli before and after single oral doses of GSK1521498 (range, 0.4-100 mg) or NTX (range, 2-50 mg). GSK1521498 had high affinity for human brain ORs (GSK1521498 effective concentration 50 = 7.10 ng ml(-1)) and there was a direct relationship between receptor occupancy (RO) and plasma concentrations of GSK1521498. However, for both NTX and its principal active metabolite in humans, 6-β-NTX, this relationship was indirect. GSK1521498, but not NTX, significantly attenuated the fMRI activation of the amygdala by a palatable food stimulus. We thus have shown how the pharmacological properties of OR antagonists can be characterised directly in humans by a novel integration of molecular and functional neuroimaging techniques. GSK1521498 was differentiated from NTX in terms of its pharmacokinetics, target affinity, plasma concentration-RO relationships and pharmacodynamic effects on food reward processing in the brain. Pharmacological differentiation of these molecules suggests that they may have different therapeutic profiles for treatment of overeating and other disorders of compulsive consumption.

  10. Brain mechanisms of drug reward and euphoria.

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    Wise, R A; Bozarth, M A

    1985-01-01

    Drugs of abuse have in common the fact that they serve as biological rewards. They presumably do so because of their ability to activate endogenous brain circuitry. By determining the brain circuitry activated by rewarding drug injections, much can be learned about the degree to which there is a common basis for the abuse liability of seemingly different drugs. The brain circuitry activated by two classes of abused drugs, psychomotor stimulants and opiates, is now partially understood; the current evidence suggests a shared mechanism of stimulant reward and opiate reward. The identified portion of the circuitry involves dopamine-containing cells of the ventral tegmental area and their fiber projections to the cells of the nucleus accumbens. Morphine activates these cells in the region of the cell bodies; it may have direct actions on receptors imbedded in the dopaminergic cell membrane, or it may act on afferent terminals that synapse on the dopaminergic cell bodies or dendrites. Cocaine and amphetamine act at the terminals of the dopaminergic fibers to nucleus accumbens and perhaps other structures. The shared activation of the dopaminergic input to nucleus accumbens accounts for the behaviorally activating and the rewarding effects of both stimulants and opiates (the opiate stimulant action is not widely known because it is usually masked by depressant actions of opiates in other, antagonistic, brain circuits). The activation of dopaminergic systems also accounts for amphetamine euphoria; it almost certainly accounts for cocaine euphoria and it probably accounts for opiate euphoria as well. Opiates and psychomotor stimulants clearly have many other actions which are not shared; nonshared actions must account for the well-known differences in the subjective effects of opiates and stimulants. One of the major nonshared actions is physical dependence. Opiates gain access to a major component of the circuitry mediating opiate physical dependence through opiate

  11. Improvement of Brain Reward Abnormalities by Antipsychotic Monotherapy in Schizophrenia

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    Nielsen, Mette Ødegaard; Rostrup, Egill; Wulff, Sanne;

    2012-01-01

    CONTEXT Schizophrenic symptoms are linked to a dysfunction of dopamine neurotransmission and the brain reward system. However, it remains unclear whether antipsychotic treatment, which blocks dopamine transmission, improves, alters, or even worsens the reward-related abnormalities. OBJECTIVE To i...

  12. Changes in reward-induced brain activation in opiate addicts

    NARCIS (Netherlands)

    Martin-Soelch, C; Chevalley, AF; Kunig, G; Missimer, J; Magyar, S; Mino, A; Schultz, W; Leenders, KL

    2001-01-01

    Many studies indicate a role of the cerebral dopaminergic reward system in addiction. Motivated by these findings, we examined in opiate addicts whether brain regions involved in the reward circuitry also react to human prototypical rewards. We measured regional cerebral blood flow (rCBF) with (H2O)

  13. Resource Allocation Problems with Concave Reward Functions

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    Grundel, S.; Borm, P.E.M.; Hamers, H.J.M.

    2013-01-01

    Abstract: In a resource allocation problem there is a common-pool resource, which has to be divided among agents. Each agent is characterized by a claim on this pool and an individual concave reward function on assigned resources. An assignment of resources is optimal if the total joint reward is ma

  14. Aerobic exercise reduces neuronal responses in food reward brain regions.

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    Evero, Nero; Hackett, Laura C; Clark, Robert D; Phelan, Suzanne; Hagobian, Todd A

    2012-05-01

    Acute exercise suppresses ad libitum energy intake, but little is known about the effects of exercise on food reward brain regions. After an overnight fast, 30 (17 men, 13 women), healthy, habitually active (age = 22.2 ± 0.7 yr, body mass index = 23.6 ± 0.4 kg/m(2), Vo(2peak) = 44.2 ± 1.5 ml·kg(-1)·min(-1)) individuals completed 60 min of exercise on a cycle ergometer or 60 min of rest (no-exercise) in a counterbalanced, crossover fashion. After each condition, blood oxygen level-dependent responses to high-energy food, low-energy food, and control visual cues, were measured by functional magnetic resonance imaging. Exercise, compared with no-exercise, significantly (P Exercise alone significantly (P exercise alone significantly (P Exercise reduced neuronal responses in brain regions consistent with reduced pleasure of food, reduced incentive motivation to eat, and reduced anticipation and consumption of food. Reduced neuronal response in these food reward brain regions after exercise is in line with the paradigm that acute exercise suppresses subsequent energy intake.

  15. Reward networks in the brain as captured by connectivity measures

    Directory of Open Access Journals (Sweden)

    Estela Camara

    2009-12-01

    Full Text Available An assortment of human behaviors is thought to be driven by rewards including reinforcement learning, novelty processing, learning, decision making, economic choice, incentive motivation, and addiction. In each case the ventral tegmental area / ventral striatum (Nucleus accumbens system (VTA-VS has been implicated as a key structure by functional imaging studies, mostly on the basis of standard, univariate analyses. Here we propose that standard fMRI analysis needs to be complemented by methods that take into account the differential connectivity of the VTA-VS system in the different behavioral contexts in order to describe reward based processes more appropriately. We first consider the wider network for reward processing as it emerged from animal experimentation. Subsequently, an example for a method to assess functional connectivity is given. Finally, we illustrate the usefulness of such analyses by examples regarding reward valuation, reward expectation and the role of reward in addiction.

  16. Toward an autonomous brain machine interface: integrating sensorimotor reward modulation and reinforcement learning.

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    Marsh, Brandi T; Tarigoppula, Venkata S Aditya; Chen, Chen; Francis, Joseph T

    2015-05-13

    For decades, neurophysiologists have worked on elucidating the function of the cortical sensorimotor control system from the standpoint of kinematics or dynamics. Recently, computational neuroscientists have developed models that can emulate changes seen in the primary motor cortex during learning. However, these simulations rely on the existence of a reward-like signal in the primary sensorimotor cortex. Reward modulation of the primary sensorimotor cortex has yet to be characterized at the level of neural units. Here we demonstrate that single units/multiunits and local field potentials in the primary motor (M1) cortex of nonhuman primates (Macaca radiata) are modulated by reward expectation during reaching movements and that this modulation is present even while subjects passively view cursor motions that are predictive of either reward or nonreward. After establishing this reward modulation, we set out to determine whether we could correctly classify rewarding versus nonrewarding trials, on a moment-to-moment basis. This reward information could then be used in collaboration with reinforcement learning principles toward an autonomous brain-machine interface. The autonomous brain-machine interface would use M1 for both decoding movement intention and extraction of reward expectation information as evaluative feedback, which would then update the decoding algorithm as necessary. In the work presented here, we show that this, in theory, is possible.

  17. Reward sensitivity is associated with brain activity during erotic stimulus processing.

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    Victor Costumero

    Full Text Available The behavioral approach system (BAS from Gray's reinforcement sensitivity theory is a neurobehavioral system involved in the processing of rewarding stimuli that has been related to dopaminergic brain areas. Gray's theory hypothesizes that the functioning of reward brain areas is modulated by BAS-related traits. To test this hypothesis, we performed an fMRI study where participants viewed erotic and neutral pictures, and cues that predicted their appearance. Forty-five heterosexual men completed the Sensitivity to Reward scale (from the Sensitivity to Punishment and Sensitivity to Reward Questionnaire to measure BAS-related traits. Results showed that Sensitivity to Reward scores correlated positively with brain activity during reactivity to erotic pictures in the left orbitofrontal cortex, left insula, and right ventral striatum. These results demonstrated a relationship between the BAS and reward sensitivity during the processing of erotic stimuli, filling the gap of previous reports that identified the dopaminergic system as a neural substrate for the BAS during the processing of other rewarding stimuli such as money and food.

  18. The brain correlates of the effects of monetary and verbal rewards on intrinsic motivation.

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    Albrecht, Konstanze; Abeler, Johannes; Weber, Bernd; Falk, Armin

    2014-01-01

    Apart from everyday duties, such as doing the laundry or cleaning the house, there are tasks we do for pleasure and enjoyment. We do such tasks, like solving crossword puzzles or reading novels, without any external pressure or force; instead, we are intrinsically motivated: we do the tasks because we enjoy doing them. Previous studies suggest that external rewards, i.e., rewards from the outside, affect the intrinsic motivation to engage in a task: while performance-based monetary rewards are perceived as controlling and induce a business-contract framing, verbal rewards praising one's competence can enhance the perceived self-determination. Accordingly, the former have been shown to decrease intrinsic motivation, whereas the latter have been shown to increase intrinsic motivation. The present study investigated the neural processes underlying the effects of monetary and verbal rewards on intrinsic motivation in a group of 64 subjects applying functional magnetic resonance imaging (fMRI). We found that, when participants received positive performance feedback, activation in the anterior striatum and midbrain was affected by the nature of the reward; compared to a non-rewarded control group, activation was higher while monetary rewards were administered. However, we did not find a decrease in activation after reward withdrawal. In contrast, we found an increase in activation for verbal rewards: after verbal rewards had been withdrawn, participants showed a higher activation in the aforementioned brain areas when they received success compared to failure feedback. We further found that, while participants worked on the task, activation in the lateral prefrontal cortex was enhanced after the verbal rewards were administered and withdrawn.

  19. Sex-Steroid Hormone Manipulation Reduces Brain Response to Reward

    DEFF Research Database (Denmark)

    Macoveanu, Julian; Henningsson, Susanne; Pinborg, Anja

    2016-01-01

    Mood disorders are twice as frequent in women than in men. Risk mechanisms for major depression include adverse responses to acute changes in sex-steroid hormone levels, eg, postpartum in women. Such adverse responses may involve an altered processing of rewards. Here, we examine how women...... regional brain activity related to the magnitude of risk during choice and to monetary reward. The GnRHa intervention caused a net reduction in ovarian sex steroids (estradiol and testosterone) and increased depression symptoms. Compared with placebo, GnRHa reduced amygdala's reactivity to high monetary......'s vulnerability for mood disorders is linked to sex-steroid dynamics by investigating the effects of a pharmacologically induced fluctuation in ovarian sex steroids on the brain response to monetary rewards. In a double-blinded placebo controlled study, healthy women were randomized to receive either placebo...

  20. Reward mechanisms in the brain and their role in dependence : evidence from neurophysiological and neuroimaging studies

    NARCIS (Netherlands)

    Martin-Soelch, C; Leenders, KL; Chevalley, AF; Missimer, J; Kunig, G; Magyar, S; Mino, A; Schultz, W

    2001-01-01

    This article reviews neuronal activity related to reward processing in primate and human brains. In the primate brain, neurophysiological methods provide a differentiated view of reward processing in a limited number of brain structures. Dopamine neurons respond to unpredictable rewards and produce

  1. Unitizing worker expertise and maximizing the brain reward centers

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Anthony Bert [Los Alamos National Laboratory

    2010-01-01

    People are experts when it comes to the work they do; unfortunately their expertise is not utilized as frequently as it could be. More opportunities need to be provided that allow people to participate in the design of their work including: accident investigations, job planning, and process improvements. Many employers use some form of job hazard analysis process to identify and document hazards and controls, but the front line worker is rarely involved. This presentation will show the core principles supporting employee involvement, provide examples where workers had brilliant ideas but no one listened, and provide examples where workers were given the opportunity to use their expertise to improve occupational safety. According to Abraham Maslow's Hierarch of Needs model, one essential human need is to be innovative and solve problems. Advances in brain science have proven, through functional magnetic resonance imaging (fMRI) studies, the brain reward pathway is activated when people are recognized for their intellectual contributions. As people contribute their expertise to improve occupational safety more frequently they will feel a sense of gratification. In addition, safety professionals will have more time to spend on strategic planning of emerging occupational safety issues. One effect of the current global recession is that SH&E professionals are asked to do more with less. Therefore, to be successful it is essential that SH&E professionals incorporate worker expertise in job planning. This will be illustrated in the presentation through an example where a worker had the answer to a difficult decision on appropriate personal protective equipment for a job but no one asked the worker for his idea during the job planning phase. Fortunately the worker was eventually consulted and his recommendation for the appropriate personal protective equipment for the job was implemented before work began. The goal of this presentation is to expand the awareness and

  2. Flavor vs Energy Sensing in Brain Reward Circuits

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    Ivan E De Araujo

    2014-07-01

    Full Text Available Sweetness functions as a potent natural reinforcer in several species, from flies to rodents to primates including humans. The appreciation of flavored stimuli is greatly enhanced when sweetness is added, the obvious example being sugar-sweetened flavored beverages (the major source of excess added calories in US diets. Different sweet substances are nevertheless attributed greater incentive value than others, with glucose-containing sugars appearing as the uppermost sweet reward. Food choices are indeed prominently determined by nutritional value, with caloric content being highly predictive of both preference and intake. Specifically, for most species studied, glucose-containing sugars are known to exert exquisitely strong effects on food choice via post-ingestive signals. Despite the relevance of the issue to public health, the identity of the physiological signals underlying glucose’s rewarding effects remains incompletely understood. Recently, however, some progress has been achieved in this front: the concept is emerging that the metabolic utilization of glucose moieties contained in sugars drives activity in brain reward circuitries (thereby presumably driving robust intake. Specifically, disruption of glucose utilization in mice was shown to produce an enduring inhibitory effect on artificial (non-nutritive sweetener intake, an effect that did not depend on sweetness perception or aversion [1]. Indeed, such an effect was not observed in mice presented with a less palatable, yet caloric, glucose solution. It is also remarkable that hungry mice shift their preferences away from artificial sweeteners in favor of glucose solutions, especially when the sugar is experienced in a food-depleted state. However, the most striking effect associated with sweet appetite appears to be the strong selectivity of certain brain circuitries to the energy content of the solutions, irrespective of sweetness per se. Indeed, it has been shown that glucose

  3. Diminished social reward anticipation in the broad autism phenotype as revealed by event-related brain potentials.

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    Cox, Anthony; Kohls, Gregor; Naples, Adam J; Mukerji, Cora E; Coffman, Marika C; Rutherford, Helena J V; Mayes, Linda C; McPartland, James C

    2015-10-01

    Diminished responsivity to reward incentives is a key contributor to the social-communication problems seen in autism spectrum disorders (ASDs). Social motivation theories suggest that individuals with ASD do not experience social interactions as rewarding, leading to negative consequences for the development of brain circuitry subserving social information. In this study, we examined neural responses to social and non-social reward anticipation in 35 typically developing young adults, examining modulation of reward sensitivity by level of autistic traits. Using an Event-related potential incentive-delay task incorporating novel, more ecologically valid forms of reward, higher expression of autistic traits was associated with an attenuated P3 response to the anticipation of social (simulated real-time video feedback from an observer), but not non-social (candy), rewards. Exploratory analyses revealed that this was unrelated to mentalizing ability. The P3 component reflects motivated attention to reward signals, suggesting attenuated motivation allocation specific to social incentives. The study extends prior findings of atypical reward anticipation in ASD, demonstrating that attenuated social reward responsiveness extends to autistic traits in the range of typical functioning. Results support the development of innovative paradigms for investigating social and non-social reward responsiveness. Insight into vulnerabilities in reward processing is critical for understanding social function in ASD.

  4. Pubertal status associations with reward and threat sensitivities and subcortical brain volumes during adolescence.

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    Urošević, Snežana; Collins, Paul; Muetzel, Ryan; Lim, Kelvin O; Luciana, Monica

    2014-08-01

    Adolescence is characterized by complex developmental processes that impact behavior, biology, and social functioning. Two such adolescence-specific processes are puberty and increases in reward sensitivity. Relations between these processes are poorly understood. The present study focused on examining unique effects of puberty, age, and sex on reward and threat sensitivities and volumes of subcortical brain structures relevant for reward/threat processing in a healthy sample of 9-18year-olds. Unlike age, pubertal status had a significant unique positive relationship with reward sensitivity. In addition, there was a trend for adolescent females to exhibit higher threat sensitivity with more advanced pubertal development and higher reward and threat sensitivity with older age. Similarly, there were significant puberty by sex interaction effects on striatal volumes, i.e., left nucleus accumbens and right pallidum. The present pattern of results suggests that pubertal development, independent of chronological age, is uniquely associated with reward hypersensitivity and with structural differences in striatal regions implicated in reward processing.

  5. Cannabinoids reward sensitivity in a neurodevelopmental animal model of schizophrenia: a brain stimulation reward study.

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    Gallo, Alexandra; Bouchard, Claude; Fortier, Emmanuel; Ducrot, Charles; Rompré, Pierre-Paul

    2014-09-01

    The comorbidity schizophrenia and cannabis has a high prevalence. The consumption of cannabis is ten times higher among schizophrenia patients, suggesting that these patients could be differentially sensitive to its motivational effects. To study this question, we investigated the motivational effects of cannabinoid agonists using the brain stimulation reward paradigm and a neurodevelopmental model of schizophrenia: neonatal ventral hippocampus lesions (NVHL). Using the curve-shift paradigm, we first compared the effect single dose (0.75mg/kg) of amphetamine in sham and NVHL rats on reward and operant responding. Then, in different groups of NVHL and sham rats, we studied the effect of delta-9-tetrahydrocannabinnol (THC, 0.5mg/kg, i.p.) and WIN55,212-2 (WIN, 1 and 3mg/kg, i.p.) Rats were initially trained to self-administer an electrical stimulation to the posterio-medial mesencephalon. Once responding was stable, reward threshold defined as the frequency required to induce a half maximum response rate was measured before and after injection of the drug or the vehicle. Results show that amphetamine enhanced reward in sham and NVHL rats, an effect that was shorter in duration in NVHL rats. THC produced a weak attenuation of reward in sham rats while WIN produced a dose-dependent attenuation in NVHL; the attenuation effect of WIN was blocked by the cannabinoid antagonist, AM251. WIN also produced an attenuation of performance in sham and NVHL rats, and this effect was partially prevented by AM251. These results provide the additional evidence that the motivational effect of cannabinoids is altered in animals with a schizophrenia-like phenotype.

  6. Opposite modulation of brain stimulation reward by NMDA and AMPA receptors in the ventral tegmental area.

    Directory of Open Access Journals (Sweden)

    Charles eDucrot

    2013-10-01

    Full Text Available Previous studies have shown that blockade of ventral midbrain (VM glutamate N-Methyl-D-Aspartate (NMDA receptors induces reward, stimulates forward locomotion and enhances brain stimulation reward. Glutamate induces two types of excitatory response on VM neurons, a fast and short lasting depolarisation mediated by a-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA receptors and a longer lasting depolarization mediated by NMDA receptors. A role for the two glutamate receptors in modulation of VM neuronal activity is evidenced by the functional change in AMPA and NMDA synaptic responses that result from repeated exposure to reward. Since both receptors contribute to the action of glutamate on VM neuronal activity, we studied the effects of VM AMPA and NMDA receptor blockade on reward induced by electrical brain stimulation. Experiments were performed on rats trained to self-administer electrical pulses in the medial posterior mesencephalon. Reward thresholds were measured with the curve-shift paradigm before and for two hours after bilateral VM microinjections of the AMPA antagonist, NBQX (2,3,-Dioxo-6-nitro-1,2,3,4-tetrahydrobenzo(fquinoxaline-7-sulfonamide, 0, 80, and 800 pmol/0.5ul/side and of a single dose (0.825 nmol/0.5ul/side of the NMDA antagonist, PPPA (2R,4S-4-(3-Phosphonopropyl-2-piperidinecarboxylic acid. NBQX produced a dose-dependent increase in reward threshold with no significant change in maximum rate of responding. Whereas PPPA injected at the same VM sites produced a significant time dependent decrease in reward threshold and increase in maximum rate of responding. We found a negative correlation between the magnitude of the attenuation effect of NBQX and the enhancement effect of PPPA; moreover, NBQX and PPPA were most effective when injected respectively into the anterior and posterior VM. These results suggest that glutamate acts on different receptor sub-types, most likely located on different VM neurons, to modulate

  7. Opposite modulation of brain stimulation reward by NMDA and AMPA receptors in the ventral tegmental area.

    Science.gov (United States)

    Ducrot, Charles; Fortier, Emmanuel; Bouchard, Claude; Rompré, Pierre-Paul

    2013-01-01

    Previous studies have shown that blockade of ventral tegmental area (VTA) glutamate N-Methyl-D-Aspartate (NMDA) receptors induces reward, stimulates forward locomotion and enhances brain stimulation reward. Glutamate induces two types of excitatory response on VTA neurons, a fast and short lasting depolarization mediated by α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptors and a longer lasting depolarization mediated by NMDA receptors. A role for the two glutamate receptors in modulation of VTA neuronal activity is evidenced by the functional change in AMPA and NMDA synaptic responses that result from repeated exposure to reward. Since both receptors contribute to the action of glutamate on VTA neuronal activity, we studied the effects of VTA AMPA and NMDA receptor blockade on reward induced by electrical brain stimulation. Experiments were performed on rats trained to self-administer electrical pulses in the medial posterior mesencephalon. Reward thresholds were measured with the curve-shift paradigm before and for 2 h after bilateral VTA microinjections of the AMPA antagonist, NBQX (2,3,-Dioxo-6-nitro-1,2,3,4-tetrahydrobenzo(f)quinoxaline-7-sulfonamide, 0, 80, and 800 pmol/0.5 μl/side) and of a single dose (0.825 nmol/0.5 μl/side) of the NMDA antagonist, PPPA (2R,4S)-4-(3-Phosphonopropyl)-2-piperidinecarboxylic acid). NBQX produced a dose-dependent increase in reward threshold with no significant change in maximum rate of responding. Whereas PPPA injected at the same VTA sites produced a significant time dependent decrease in reward threshold and increase in maximum rate of responding. We found a negative correlation between the magnitude of the attenuation effect of NBQX and the enhancement effect of PPPA; moreover, NBQX and PPPA were most effective when injected, respectively, into the anterior and posterior VTA. These results suggest that glutamate acts on different receptor sub-types, most likely located on different VTA neurons, to

  8. Independent functional connectivity networks underpin food and monetary reward sensitivity in excess weight.

    Science.gov (United States)

    Verdejo-Román, Juan; Fornito, Alex; Soriano-Mas, Carles; Vilar-López, Raquel; Verdejo-García, Antonio

    2017-02-01

    Overvaluation of palatable food is a primary driver of obesity, and is associated with brain regions of the reward system. However, it remains unclear if this network is specialized in food reward, or generally involved in reward processing. We used functional magnetic resonance imaging (fMRI) to characterize functional connectivity during processing of food and monetary rewards. Thirty-nine adults with excess weight and 37 adults with normal weight performed the Willingness to Pay for Food task and the Monetary Incentive Delay task in the fMRI scanner. A data-driven graph approach was applied to compare whole-brain, task-related functional connectivity between groups. Excess weight was associated with decreased functional connectivity during the processing of food rewards in a network involving primarily frontal and striatal areas, and increased functional connectivity during the processing of monetary rewards in a network involving principally frontal and parietal areas. These two networks were topologically and anatomically distinct, and were independently associated with BMI. The processing of food and monetary rewards involve segregated neural networks, and both are altered in individuals with excess weight.

  9. Dopamine in the Brain: Hypothesizing Surfeit or Deficit Links to Reward and Addiction

    Science.gov (United States)

    Blum, Kenneth; Thanos, Peter K.; Oscar-Berman, Marlene; Febo, Marcelo; Baron, David; Badgaiyan, Rajendra D.; Gardner, Eliot; Demetrovics, Zsolt; Fahlke, Claudia; Haberstick, Brett C.; Dushaj, Kristina; Gold, Mark S.

    2016-01-01

    Recently there has been debate concerning the role of brain dopamine in reward and addiction. David Nutt and associates eloquently proposed that dopamine (DA) may be central to psycho stimulant dependence and some what important for alcohol, but not important for opiates, nicotine or even cannabis. Others have also argued that surfeit theories can explain for example cocaine seeking behavior as well as non-substance-related addictive behaviors. It seems prudent to distinguish between what constitutes “surfeit” compared to” deficit” in terms of short-term (acute) and long-term (chronic) brain reward circuitry responsivity. In an attempt to resolve controversy regarding the contributions of mesolimbic DA systems to reward, we review the three main competing explanatory categories: “liking”, “learning”, and “wanting”. They are (a) the hedonic impact -liking reward, (b) the ability to predict rewarding effects-learning and (c) the incentive salience of reward-related stimuli -wanting. In terms of acute effects, most of the evidence seems to favor the “surfeit theory”. Due to preferential dopamine release at mesolimbic-VTA-caudate-accumbens loci most drugs of abuse and Reward Deficiency Syndrome (RDS) behaviors have been linked to heightened feelings of well-being and hyperdopaminergic states.The “dopamine hypotheses” originally thought to be simple, is now believed to be quite complex and involves encoding the set point of hedonic tone, encoding attention, reward expectancy, and incentive motivation. Importantly, Willuhn et al. shows that in a self-administration paradigm, (chronic) excessive use of cocaine is caused by decreased phasic dopamine signaling in the striatum. In terms of chronic addictions, others have shown a blunted responsivity at brain reward sites with food, nicotine, and even gambling behavior. Finally, we are cognizant of the differences in dopaminergic function as addiction progresses and argue that relapse may be tied

  10. Brain areas activated by uncertain reward-based decision-making in healthy volunteers

    Institute of Scientific and Technical Information of China (English)

    Zongjun Guo; Juan Chen; Shien Liu; Yuhuan Li; Bo Sun; Zhenbo Gao

    2013-01-01

    Reward-based decision-making has been found to activate several brain areas, including the ven-trolateral prefrontal lobe, orbitofrontal cortex, anterior cingulate cortex, ventral striatum, and meso-limbic dopaminergic system. In this study, we observed brain areas activated under three degrees of uncertainty in a reward-based decision-making task (certain, risky, and ambiguous). The tasks were presented using a brain function audiovisual stimulation system. We conducted brain scans of 15 healthy volunteers using a 3.0T magnetic resonance scanner. We used SPM8 to analyze the location and intensity of activation during the reward-based decision-making task, with respect to the three conditions. We found that the orbitofrontal cortex was activated in the certain reward con-dition, while the prefrontal cortex, precentral gyrus, occipital visual cortex, inferior parietal lobe, ce-rebel ar posterior lobe, middle temporal gyrus, inferior temporal gyrus, limbic lobe, and midbrain were activated during the ‘risk’ condition. The prefrontal cortex, temporal pole, inferior temporal gyrus, occipital visual cortex, and cerebel ar posterior lobe were activated during ambiguous deci-sion-making. The ventrolateral prefrontal lobe, frontal pole of the prefrontal lobe, orbitofrontal cortex, precentral gyrus, inferior temporal gyrus, fusiform gyrus, supramarginal gyrus, inferior parietal lo-bule, and cerebel ar posterior lobe exhibited greater activation in the‘risk’ than in the‘certain’ con-dition (P<0.05). The frontal pole and dorsolateral region of the prefrontal lobe, as wel as the ce-rebel ar posterior lobe, showed significantly greater activation in the ‘ambiguous’ condition com-pared to the ‘risk’ condition (P < 0.05). The prefrontal lobe, occipital lobe, parietal lobe, temporal lobe, limbic lobe, midbrain, and posterior lobe of the cerebel um were activated during deci-sion-making about uncertain rewards. Thus, we observed different levels and regions of

  11. Reward-based hypertension control by a synthetic brain-dopamine interface.

    Science.gov (United States)

    Rössger, Katrin; Charpin-El Hamri, Ghislaine; Fussenegger, Martin

    2013-11-05

    Synthetic biology has significantly advanced the design of synthetic trigger-controlled devices that can reprogram mammalian cells to interface with complex metabolic activities. In the brain, the neurotransmitter dopamine coordinates communication with target neurons via a set of dopamine receptors that control behavior associated with reward-driven learning. This dopamine transmission has recently been suggested to increase central sympathetic outflow, resulting in plasma dopamine levels that correlate with corresponding brain activities. By functionally rewiring the human dopamine receptor D1 (DRD1) via the second messenger cyclic adenosine monophosphate (cAMP) to synthetic promoters containing cAMP response element-binding protein 1(CREB1)-specific cAMP-responsive operator modules, we have designed a synthetic dopamine-sensitive transcription controller that reversibly fine-tunes specific target gene expression at physiologically relevant brain-derived plasma dopamine levels. Following implantation of circuit-transgenic human cell lines insulated by semipermeable immunoprotective microcontainers into mice, the designer device interfaced with dopamine-specific brain activities and produced a systemic expression response when the animal's reward system was stimulated by food, sexual arousal, or addictive drugs. Reward-triggered brain activities were able to remotely program peripheral therapeutic implants to produce sufficient amounts of the atrial natriuretic peptide, which reduced the blood pressure of hypertensive mice to the normal physiologic range. Seamless control of therapeutic transgenes by subconscious behavior may provide opportunities for treatment strategies of the future.

  12. Neural signal during immediate reward anticipation in schizophrenia: Relationship to real-world motivation and function.

    Science.gov (United States)

    Subramaniam, Karuna; Hooker, Christine I; Biagianti, Bruno; Fisher, Melissa; Nagarajan, Srikantan; Vinogradov, Sophia

    2015-01-01

    Amotivation in schizophrenia is a central predictor of poor functioning, and is thought to occur due to deficits in anticipating future rewards, suggesting that impairments in anticipating pleasure can contribute to functional disability in schizophrenia. In healthy comparison (HC) participants, reward anticipation is associated with activity in frontal-striatal networks. By contrast, schizophrenia (SZ) participants show hypoactivation within these frontal-striatal networks during this motivated anticipatory brain state. Here, we examined neural activation in SZ and HC participants during the anticipatory phase of stimuli that predicted immediate upcoming reward and punishment, and during the feedback/outcome phase, in relation to trait measures of hedonic pleasure and real-world functional capacity. SZ patients showed hypoactivation in ventral striatum during reward anticipation. Additionally, we found distinct differences between HC and SZ groups in their association between reward-related immediate anticipatory neural activity and their reported experience of pleasure. HC participants recruited reward-related regions in striatum that significantly correlated with subjective consummatory pleasure, while SZ patients revealed activation in attention-related regions, such as the IPL, which correlated with consummatory pleasure and functional capacity. These findings may suggest that SZ patients activate compensatory attention processes during anticipation of immediate upcoming rewards, which likely contribute to their functional capacity in daily life.

  13. Neural signal during immediate reward anticipation in schizophrenia: Relationship to real-world motivation and function

    Directory of Open Access Journals (Sweden)

    Karuna Subramaniam

    2015-01-01

    Full Text Available Amotivation in schizophrenia is a central predictor of poor functioning, and is thought to occur due to deficits in anticipating future rewards, suggesting that impairments in anticipating pleasure can contribute to functional disability in schizophrenia. In healthy comparison (HC participants, reward anticipation is associated with activity in frontal–striatal networks. By contrast, schizophrenia (SZ participants show hypoactivation within these frontal–striatal networks during this motivated anticipatory brain state. Here, we examined neural activation in SZ and HC participants during the anticipatory phase of stimuli that predicted immediate upcoming reward and punishment, and during the feedback/outcome phase, in relation to trait measures of hedonic pleasure and real-world functional capacity. SZ patients showed hypoactivation in ventral striatum during reward anticipation. Additionally, we found distinct differences between HC and SZ groups in their association between reward-related immediate anticipatory neural activity and their reported experience of pleasure. HC participants recruited reward-related regions in striatum that significantly correlated with subjective consummatory pleasure, while SZ patients revealed activation in attention-related regions, such as the IPL, which correlated with consummatory pleasure and functional capacity. These findings may suggest that SZ patients activate compensatory attention processes during anticipation of immediate upcoming rewards, which likely contribute to their functional capacity in daily life.

  14. Rewards.

    Science.gov (United States)

    Gunderman, Richard B; Kamer, Aaron P

    2011-05-01

    For much of the 20th century, psychologists and economists operated on the assumption that work is devoid of intrinsic rewards, and the only way to get people to work harder is through the use of rewards and punishments. This so-called carrot-and-stick model of workplace motivation, when applied to medical practice, emphasizes the use of financial incentives and disincentives to manipulate behavior. More recently, however, it has become apparent that, particularly when applied to certain kinds of work, such approaches can be ineffective or even frankly counterproductive. Instead of focusing on extrinsic rewards such as compensation, organizations and their leaders need to devote more attention to the intrinsic rewards of work itself. This article reviews this new understanding of rewards and traces out its practical implications for radiology today.

  15. Flavor vs Energy Sensing in Brain Reward Circuits

    OpenAIRE

    de Araujo, Ivan E.

    2014-01-01

    Sweetness functions as a potent natural reinforcer in several species, from flies to rodents to primates including humans. The appreciation of flavored stimuli is greatly enhanced when sweetness is added, the obvious example being sugar-sweetened flavored beverages (the major source of excess added calories in US diets). Different sweet substances are nevertheless attributed greater incentive value than others, with glucose-containing sugars appearing as the uppermost sweet reward. Food choi...

  16. Alterations of the Brain Reward System in Antipsychotic Naïve Schizophrenia Patients

    DEFF Research Database (Denmark)

    Nielsen, Mette Ødegaard; Rostrup, Egill; Wulff, Sanne;

    2012-01-01

    BACKGROUND: Various schizophrenic symptoms are suggested to be linked to a dysfunction of the brain reward system. Several studies have found alterations in the reward processing in patients with schizophrenia; however, most previous findings might be confounded by medication effects. METHODS...... as arousing events) into behavioral salience (events where a predicted reward requires performance) and valence anticipation (the anticipation of a monetarily significant outcome). Furthermore, the evaluation of monetary gain and loss was assessed. RESULTS: During reward anticipation, patients had...

  17. GLP-1 receptor activation modulates appetite- and reward-related brain areas in humans.

    Science.gov (United States)

    van Bloemendaal, Liselotte; IJzerman, Richard G; Ten Kulve, Jennifer S; Barkhof, Frederik; Konrad, Robert J; Drent, Madeleine L; Veltman, Dick J; Diamant, Michaela

    2014-12-01

    Gut-derived hormones, such as GLP-1, have been proposed to relay information to the brain to regulate appetite. GLP-1 receptor agonists, currently used for the treatment of type 2 diabetes (T2DM), improve glycemic control and stimulate satiety, leading to decreases in food intake and body weight. We hypothesized that food intake reduction after GLP-1 receptor activation is mediated through appetite- and reward-related brain areas. Obese T2DM patients and normoglycemic obese and lean individuals (n = 48) were studied in a randomized, crossover, placebo-controlled trial. Using functional MRI, we determined the acute effects of intravenous administration of the GLP-1 receptor agonist exenatide, with or without prior GLP-1 receptor blockade using exendin 9-39, on brain responses to food pictures during a somatostatin pancreatic-pituitary clamp. Obese T2DM patients and normoglycemic obese versus lean subjects showed increased brain responses to food pictures in appetite- and reward-related brain regions (insula and amygdala). Exenatide versus placebo decreased food intake and food-related brain responses in T2DM patients and obese subjects (in insula, amygdala, putamen, and orbitofrontal cortex). These effects were largely blocked by prior GLP-1 receptor blockade using exendin 9-39. Our findings provide novel insights into the mechanisms by which GLP-1 regulates food intake and how GLP-1 receptor agonists cause weight loss.

  18. Using the Neuroadaptagen KB200z™ to Ameliorate Terrifying, Lucid Nightmares in RDS Patients: the Role of Enhanced, Brain-Reward, Functional Connectivity and Dopaminergic Homeostasis

    OpenAIRE

    Thomas McLaughlin; Kenneth Blum; Marlene Oscar-Berman; Marcelo Febo; Zsolt Demetrovics; Gozde Agan; James Fratantonio; Gold, Mark S.

    2015-01-01

    Background: Lucid Dreams are a form of dream life, during which the dreamer may be aware that he/she is dreaming, can stop/re-start the dreams, depending on the pleasantness or unpleasant nature of the dream, and experiences the dream as if he/she were fully awake. Depending on their content, they may be pleasant, un-pleasant or terrifying, at least in the context of patients, who also exhibit characteristics of Reward Deficiency Syndrome (RDS) and Posttraumatic Stress Disorder (PTSD). Ca...

  19. Methylphenidate and brain activity in a reward/conflict paradigm: role of the insula in task performance.

    Science.gov (United States)

    Ivanov, Iliyan; Liu, Xun; Clerkin, Suzanne; Schulz, Kurt; Fan, Jin; Friston, Karl; London, Edythe D; Schwartz, Jeffrey; Newcorn, Jeffrey H

    2014-06-01

    Psychostimulants, such as methylphenidate, are thought to improve information processing in motivation-reward and attention-activation networks by enhancing the effects of more relevant signals and suppressing those of less relevant ones; however the nature of such reciprocal influences remains poorly understood. To explore this question, we tested the effect of methylphenidate on performance and associated brain activity in the Anticipation, Conflict, Reward (ACR) task. Sixteen healthy adult volunteers, ages 21-45, were scanned twice using functional magnetic resonance imaging (fMRI) as they performed the ACR task under placebo and methylphenidate conditions. A three-way repeated measures analysis of variance, with cue (reward vs. non-reward), target (congruent vs. incongruent) and medication condition (methylphenidate vs. placebo) as the factors, was used to analyze behaviors on the task. Blood oxygen level dependent (BOLD) signals, reflecting task-related neural activity, were evaluated using linear contrasts. Participants exhibited significantly greater accuracy in the methylphenidate condition than the placebo condition. Compared with placebo, the methylphenidate condition also was associated with lesser task-related activity in components of attention-activation systems irrespective of the reward cue, and less task-related activity in components of the reward-motivation system, particularly the insula, during reward trials irrespective of target difficulty. These results suggest that methylphenidate enhances task performance by improving efficiency of information processing in both reward-motivation and in attention-activation systems.

  20. Neuroethics of deep brain stimulation for mental disorders: brain stimulation reward in humans.

    Science.gov (United States)

    Oshima, Hideki; Katayama, Yoichi

    2010-01-01

    The theoretical basis of some deep brain stimulation (DBS) trials undertaken in the early years was the phenomenon of "brain stimulation reward (BSR)," which was first identified in rats. The animals appeared to be rewarded by pleasure caused by the stimulation of certain brain regions (reward system), such as the septal area. "Self-stimulation" experiments, in which rats were allowed to stimulate their own brain by pressing a freely accessible lever, they quickly learned lever pressing and sometimes continued to stimulate until they exhausted themselves. BSR was also observed with DBS of the septal area in humans. DBS trials in later years were undertaken on other theoretical bases, but unexpected BSR was sometimes induced by stimulation of some areas, such as the locus coeruleus complex. When BSR was induced, the subjects experienced feelings that were described as "cheerful," "alert," "good," "well-being," "comfort," "relaxation," "joy," or "satisfaction." Since the DBS procedure is equivalent to a "self-stimulation" experiment, they could become "addicted to the stimulation itself" or "compulsive about the stimulation," and stimulate themselves "for the entire day," "at maximum amplitude" and, in some instances, "into convulsions." DBS of the reward system has recently been applied to alleviate anhedonia in patients with refractory major depression. Although this approach appears promising, there remains a difficult problem: who can adjust their feelings and reward-oriented behavior within the normal range? With a self-stimulation procedure, the BSR may become uncontrollable. To develop DBS to the level of a standard therapy for mental disorders, we need to discuss "Who has the right to control the mental condition?" and "Who makes decisions" on "How much control is appropriate?" in daily life.

  1. Using the Neuroadaptagen KB200z™ to Ameliorate Terrifying, Lucid Nightmares in RDS Patients: the Role of Enhanced, Brain-Reward, Functional Connectivity and Dopaminergic Homeostasis

    Directory of Open Access Journals (Sweden)

    Thomas McLaughlin

    2015-03-01

    Full Text Available Background: Lucid Dreams are a form of dream life, during which the dreamer may be aware that he/she is dreaming, can stop/re-start the dreams, depending on the pleasantness or unpleasant nature of the dream, and experiences the dream as if he/she were fully awake. Depending on their content, they may be pleasant, un-pleasant or terrifying, at least in the context of patients, who also exhibit characteristics of Reward Deficiency Syndrome (RDS and Posttraumatic Stress Disorder (PTSD. Case Series: We present eight clinical cases, with known substance abuse, childhood abuse and diagnosed PTSD/RDS. The administration of a putative dopamine agonist, KB200Z™, was associated with the elimination of unpleasant and/or terrifying, lucid dreams in 87.5% of the cases presented, whereas one very heavy cocaine abuser showed a minimal response. These results required the continuous use of this nutraceutical. The lucid dreams themselves were distinguishable from typical, PTSD nightmares insofar as their content did not appear to reflect a symbolic rendition of an originally-experienced, historical trauma. Each of the cases was diagnosed with a form of RDS, i.e., ADHD, ADD, and/or Tourette’s syndrome. They all also suffered from some form of Post- Traumatic-Stress-Disorder (PTSD and other psychiatric diagnoses as well. Conclusion: The reduction or elimination of terrifying Lucid Dreams seemed to be dependent on KB220Z, whereby voluntary stopping of the agent results in reinstatement of the terrifying non-pleasant nature of the dreams. Following more required research on a much larger population we anticipate confirmation of these seemingly interesting observations. If these results in a small number of patients are indeed confirmed we may have found a frontline solution to a very perplexing and complicated symptom known as lucid dreams.

  2. Problematic internet use is associated with structural alterations in the brain reward system in females.

    Science.gov (United States)

    Altbäcker, Anna; Plózer, Enikő; Darnai, Gergely; Perlaki, Gábor; Horváth, Réka; Orsi, Gergely; Nagy, Szilvia Anett; Bogner, Péter; Schwarcz, Attila; Kovács, Norbert; Komoly, Sámuel; Clemens, Zsófia; Janszky, József

    2016-12-01

    Neuroimaging findings suggest that excessive Internet use shows functional and structural brain changes similar to substance addiction. Even though it is still under debate whether there are gender differences in case of problematic use, previous studies by-passed this question by focusing on males only or by using gender matched approach without controlling for potential gender effects. We designed our study to find out whether there are structural correlates in the brain reward system of problematic Internet use in habitual Internet user females. T1-weighted Magnetic Resonance (MR) images were collected in 82 healthy habitual Internet user females. Structural brain measures were investigated using both automated MR volumetry and voxel based morphometry (VBM). Self-reported measures of problematic Internet use and hours spent online were also assessed. According to MR volumetry, problematic Internet use was associated with increased grey matter volume of bilateral putamen and right nucleus accumbens while decreased grey matter volume of orbitofrontal cortex (OFC). Similarly, VBM analysis revealed a significant negative association between the absolute amount of grey matter OFC and problematic Internet use. Our findings suggest structural brain alterations in the reward system usually related to addictions are present in problematic Internet use.

  3. Reinforcing brain stimulation in competition with water reward and shock avoidance.

    Science.gov (United States)

    VALENSTEIN, E S; BEER, B

    1962-09-28

    Employing response rate as the index of reinforcing strength in self-stimulation experiments is questioned. With water reward or shock avoidance placed in competition with brain stimulation, self-stimulation rate does not reflect relative reinforcement value. The results agree with preference tests which show that, for a given electrode site, stimulus intensity, not rate, is directly related to reward strength.

  4. Preliminary Evidence for Impaired Brain Activity of Neural Reward Processing in Children and Adolescents with Reactive Attachment Disorder.

    Science.gov (United States)

    Tomoda, Akemi

    2016-01-01

    Childhood maltreatment, which markedly increases risks for psychopathology, is associated with structural and functional brain differences. Especially, exposure to parental verbal abuse (PVA) or interparental violence during childhood is associated with negative outcomes such as depression, posttraumatic stress disorder (PTSD), and reduced cognitive abilities. Other forms of childhood maltreatment have been associated with brain structure or developmental alteration. Our earlier studies elucidated potential discernible effects of PVA and witnessing domestic violence during childhood on brain morphology, including gray matter volume or cortical thickness. Brain regions that process and convey the adverse sensory input of the abuse might be modified specifically by such experiences, particularly in subjects exposed to a single type of maltreatment. Exposure to multiple types of maltreatment is more commonly associated with morphological alterations in the corticolimbic regions. These findings fit with preclinical studies showing that sensory cortices are highly plastic structures. Using tasks with high and low monetary rewards while subjects underwent functional MRI, we also examined whether neural activity during reward processing was altered, or not, in children and adolescents with reactive attachment disorder (RAD). Significantly reduced activity in the caudate and nucleus accumbens was observed during a high monetary reward condition in the RAD group compared to the typically developed group. The striatal neural reward activity in the RAD group was also markedly decreased. The present results suggest that dopaminergic dysfunction occurred in the striatum in children and adolescents with RAD, potentially leading to a future risk of psychiatric disorders such as dependence.

  5. The computational psychiatry of reward: Broken brains or misguided minds?

    Directory of Open Access Journals (Sweden)

    Michael eMoutoussis

    2015-09-01

    Full Text Available Research into the biological basis of emotional and motivational disorders is in danger of riding roughshod over a patient-centred psychiatry and falling into the dualist errors of the past, i.e. by treating mind and brain as conceptually distinct. We argue that a psychiatry informed by computational neuroscience, computational psychiatry, can obviate this danger. Through a focus on the reasoning processes by which humans attempt to maximise reward (and minimise punishment, and how such reasoning is expressed neurally, computational psychiatry can render obsolete the polarity between biological and psychosocial conceptions of illness. Here, the term 'psychological' comes to refer to information processing performed by biological agents, seen in light of underlying goals. We reflect on the implications of this perspective for a definition of mental disorder, including what is entailed in asserting that a particular disorder is ‘biological’ or ‘psychological’ in origin. We propose that a computational approach assists in understanding the topography of mental disorder, while cautioning that the point at which eccentric reasoning constitutes disorder often remains a matter of cultural judgement.

  6. General functioning predicts reward and punishment learning in schizophrenia.

    Science.gov (United States)

    Somlai, Zsuzsanna; Moustafa, Ahmed A; Kéri, Szabolcs; Myers, Catherine E; Gluck, Mark A

    2011-04-01

    Previous studies investigating feedback-driven reinforcement learning in patients with schizophrenia have provided mixed results. In this study, we explored the clinical predictors of reward and punishment learning using a probabilistic classification learning task. Patients with schizophrenia (n=40) performed similarly to healthy controls (n=30) on the classification learning task. However, more severe negative and general symptoms were associated with lower reward-learning performance, whereas poorer general psychosocial functioning was correlated with both lower reward- and punishment-learning performances. Multiple linear regression analyses indicated that general psychosocial functioning was the only significant predictor of reinforcement learning performance when education, antipsychotic dose, and positive, negative and general symptoms were included in the analysis. These results suggest a close relationship between reinforcement learning and general psychosocial functioning in schizophrenia.

  7. Dopamine neurons share common response function for reward prediction error.

    Science.gov (United States)

    Eshel, Neir; Tian, Ju; Bukwich, Michael; Uchida, Naoshige

    2016-03-01

    Dopamine neurons are thought to signal reward prediction error, or the difference between actual and predicted reward. How dopamine neurons jointly encode this information, however, remains unclear. One possibility is that different neurons specialize in different aspects of prediction error; another is that each neuron calculates prediction error in the same way. We recorded from optogenetically identified dopamine neurons in the lateral ventral tegmental area (VTA) while mice performed classical conditioning tasks. Our tasks allowed us to determine the full prediction error functions of dopamine neurons and compare them to each other. We found marked homogeneity among individual dopamine neurons: their responses to both unexpected and expected rewards followed the same function, just scaled up or down. As a result, we were able to describe both individual and population responses using just two parameters. Such uniformity ensures robust information coding, allowing each dopamine neuron to contribute fully to the prediction error signal.

  8. Functional changes of the reward system underlie blunted response to social gaze in cocaine users.

    Science.gov (United States)

    Preller, Katrin H; Herdener, Marcus; Schilbach, Leonhard; Stämpfli, Philipp; Hulka, Lea M; Vonmoos, Matthias; Ingold, Nina; Vogeley, Kai; Tobler, Philippe N; Seifritz, Erich; Quednow, Boris B

    2014-02-18

    Social interaction deficits in drug users likely impede treatment, increase the burden of the affected families, and consequently contribute to the high costs for society associated with addiction. Despite its significance, the neural basis of altered social interaction in drug users is currently unknown. Therefore, we investigated basal social gaze behavior in cocaine users by applying behavioral, psychophysiological, and functional brain-imaging methods. In study I, 80 regular cocaine users and 63 healthy controls completed an interactive paradigm in which the participants' gaze was recorded by an eye-tracking device that controlled the gaze of an anthropomorphic virtual character. Valence ratings of different eye-contact conditions revealed that cocaine users show diminished emotional engagement in social interaction, which was also supported by reduced pupil responses. Study II investigated the neural underpinnings of changes in social reward processing observed in study I. Sixteen cocaine users and 16 controls completed a similar interaction paradigm as used in study I while undergoing functional magnetic resonance imaging. In response to social interaction, cocaine users displayed decreased activation of the medial orbitofrontal cortex, a key region of reward processing. Moreover, blunted activation of the medial orbitofrontal cortex was significantly correlated with a decreased social network size, reflecting problems in real-life social behavior because of reduced social reward. In conclusion, basic social interaction deficits in cocaine users as observed here may arise from altered social reward processing. Consequently, these results point to the importance of reinstatement of social reward in the treatment of stimulant addiction.

  9. Witnessing hateful people in pain modulates brain activity in regions associated with physical pain and reward.

    Directory of Open Access Journals (Sweden)

    Glenn Ryan Fox

    2013-10-01

    Full Text Available How does witnessing a hateful person in pain compare to witnessing a likable person in pain? The current study compared the brain bases for how we perceive likable people in pain with those of viewing hateful people in pain. While social bonds are built through sharing the plight and pain of others in the name of empathy, viewing a hateful person in pain also has many potential ramifications. In this functional Magnetic Resonance Imaging (fMRI study, Caucasian Jewish male participants viewed videos of (1 disliked, hateful, anti-Semitic individuals, and (2 liked, non-hateful, tolerant individuals in pain. The results showed that, compared with viewing liked people, viewing hateful people in pain elicited increased responses in regions associated with observation of physical pain (the insular cortex, the anterior cingulate cortex, and the somatosensory cortex, reward processing (the striatum, and frontal regions associated with emotion regulation. Functional connectivity analyses revealed connections between seed regions in the left anterior cingulate cortex and right insular cortex with reward regions, the amygdala, and frontal regions associated with emotion regulation. These data indicate that regions of the brain active while viewing someone in pain may be more active in response to the danger or threat posed by witnessing the pain of a hateful individual more so than the desire to empathize with a likable person’s pain.

  10. Deep Brain Stimulation of the Subthalamic Nucleus improves Reward-based decision-learning in Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    Nelleke Corine Van Wouwe

    2011-04-01

    Full Text Available Recently, the subthalamic nucleus (STN has been shown to be critically involved in decision-making, action selection, and motor control. Here we investigate the effect of deep brain stimulation (DBS of the STN on reward-based decision-learning in patients diagnosed with Parkinson’s disease (PD. We determined computational measures of outcome evaluation and reward prediction from PD patients who performed a probabilistic reward-based decision-learning task. In previous work, these measures covaried with activation in the nucleus caudatus (outcome evaluation during the early phases of learning and the putamen (reward prediction during later phases of learning. We observed that stimulation of the STN motor regions in PD patients served to improve reward-based decision-learning, probably through its effect on activity in frontostriatal motor loops (prominently involving the putamen and, hence, reward prediction. In a subset of relatively younger patients with relatively shorter disease duration, the effects of DBS appeared to spread to more cognitive regions of the STN, benefitting loops that connect the caudate to various prefrontal areas important for outcome evaluation. These results highlight positive effects of STN stimulation on cognitive functions that may benefit PD patients in daily-life association-learning situations.

  11. Fifty Years in the Development of a Glutaminergic-Dopaminergic Optimization Complex (KB220) to Balance Brain Reward Circuitry in Reward Deficiency Syndrome: A Pictorial

    Science.gov (United States)

    Blum, K; Febo, M; Badgaiyan, RD

    2016-01-01

    Dopamine along with other chemical messengers like serotonin, cannabinoids, endorphins and glutamine, play significant roles in brain reward processing. There is a devastating opiate/opioid epidemicin the United States. According to the Centers for Disease Control and Prevention (CDC), at least 127 people, young and old, are dying every day due to narcotic overdose and alarmingly heroin overdose is on the rise. The Food and Drug Administration (FDA) has approved some Medication-Assisted Treatments (MATs) for alcoholism, opiate and nicotine dependence, but nothing for psychostimulant and cannabis abuse. While these pharmaceuticals are essential for the short-term induction of “psychological extinction,” in the long-term caution is necessary because their use favors blocking dopaminergic function indispensable for achieving normal satisfaction in life. The two institutions devoted to alcoholism and drug dependence (NIAAA & NIDA) realize that MATs are not optimal and continue to seek better treatment options. We review, herein, the history of the development of a glutaminergic-dopaminergic optimization complex called KB220 to provide for the possible eventual balancing of the brain reward system and the induction of “dopamine homeostasis.” This complex may provide substantial clinical benefit to the victims of Reward Deficiency Syndrome (RDS) and assist in recovery from iatrogenically induced addiction to unwanted opiates/opioids and other addictive behaviors. PMID:27840857

  12. Involvement of the GABAergic septo-hippocampal pathway in brain stimulation reward.

    Directory of Open Access Journals (Sweden)

    Germán Vega-Flores

    Full Text Available The hippocampus is a structure related to several cognitive processes, but not very much is known about its putative involvement in positive reinforcement. In its turn, the septum has been related to instrumental brain stimulation reward (BSR by its electrical stimulation with trains of pulses. Although the anatomical relationships of the septo-hippocampal pathway are well established, the functional relationship between these structures during rewarding behaviors remains poorly understood. To explore hippocampal mechanisms involved in BSR, CA3-evoked field excitatory and inhibitory postsynaptic potentials (fEPSPs, fIPSPs were recorded in the CA1 area during BSR in alert behaving mice. The synaptic efficiency was determined from changes in fEPSP and fIPSP amplitudes across the learning of a BSR task. The successive BSR sessions evoked a progressive increase of the performance in inverse relationship with a decrease in the amplitude of fEPSPs, but not of fIPSPs. Additionally, we evaluated CA1 local field potentials (LFPs during a preference task, comparing 8-, 20-, and 100-Hz trains of septal BSR. We corroborate a clear preference for BSR at 100 Hz (in comparison with BSR at 20 Hz or 8 Hz, in parallel with an increase in the spectral power of the low theta band, and a decrease in the gamma. These results were replicated by intrahippocampal injections of a GABAB antagonist. Thus, the GABAergic septo-hippocampal pathway seems to carry information involved in the encoding of reward properties, where GABAB receptors seem to play a key role. With regard to the dorsal hippocampus, fEPSPs evoked at the CA3-CA1 synapse seem to reflect the BSR learning process, while hippocampal rhythmic activities are more related to reward properties.

  13. Abnormal reward functioning across substance use disorders and major depressive disorder: Considering reward as a transdiagnostic mechanism.

    Science.gov (United States)

    Baskin-Sommers, Arielle R; Foti, Dan

    2015-11-01

    A common criticism of the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 2013) is that its criteria are based more on behavioral descriptions than on underlying biological mechanisms. Increasingly, calls have intensified for a more biologically-based approach to conceptualizing, studying, and treating psychological disorders, as exemplified by the Research Domain Criteria Project (RDoC). Among the most well-studied neurobiological mechanisms is reward processing. Moreover, individual differences in reward sensitivity are related to risk for substance abuse and depression. The current review synthesizes the available preclinical, electrophysiological, and neuroimaging literature on reward processing from a transdiagnostic, multidimensional perspective. Findings are organized with respect to key reward constructs within the Positive Valence Systems domain of the RDoC matrix, including initial responsiveness to reward (physiological 'liking'), approach motivation (physiological 'wanting'), and reward learning/habit formation. In the current review, we (a) describe the neural basis of reward, (b) elucidate differences in reward activity in substance abuse and depression, and (c) suggest a framework for integrating these disparate literatures and discuss the utility of shifting focus from diagnosis to process for understanding liability and co-morbidity. Ultimately, we believe that an integrative focus on abnormal reward functioning across the full continuum of clinically heterogeneous samples, rather than within circumscribed diagnostic categories, might actually help to refine the phenotypes and improve the prediction of onset and recovery of these disorders.

  14. Neuroendocrinology and brain imaging of reward in eating disorders: A possible key to the treatment of anorexia nervosa and bulimia nervosa.

    Science.gov (United States)

    Monteleone, Alessio Maria; Castellini, Giovanni; Volpe, Umberto; Ricca, Valdo; Lelli, Lorenzo; Monteleone, Palmiero; Maj, Mario

    2017-03-01

    Anorexia nervosa and bulimia nervosa are severe eating disorders whose etiopathogenesis is still unknown. Clinical features suggest that eating disorders may develop as reward-dependent syndromes, since eating less food is perceived as rewarding in anorexia nervosa while consumption of large amounts of food during binge episodes in bulimia nervosa aims at reducing the patient's negative emotional states. Therefore, brain reward mechanisms have been a major focus of research in the attempt to contribute to the comprehension of the pathophysiology of these disorders. Structural brain imaging data provided the evidence that brain reward circuits may be altered in patients with anorexia or bulimia nervosa. Similarly, functional brain imaging studies exploring the activation of brain reward circuits by food stimuli as well as by stimuli recognized to be potentially rewarding for eating disordered patients, such as body image cues or stimuli related to food deprivation and physical hyperactivity, showed several dysfunctions in ED patients. Moreover, very recently, it has been demonstrated that some of the biochemical homeostatic modulators of eating behavior are also implicated in the regulation of food-related and non-food-related reward, representing a possible link between the aberrant behaviors of ED subjects and their hypothesized deranged reward processes. In particular, changes in leptin and ghrelin occur in patients with anorexia or bulimia nervosa and have been suggested to represent not only homeostatic adaptations to an altered energy balance but to contribute also to the acquisition and/or maintenance of persistent starvation, binge eating and physical hyperactivity, which are potentially rewarding for ED patients. On the basis of such findings new pathogenetic models of EDs have been proposed, and these models may provide new theoretical basis for the development of innovative treatment strategies, either psychological and pharmacological, with the aim to

  15. Peers Increase Adolescent Risk Taking by Enhancing Activity in the Brain's Reward Circuitry

    Science.gov (United States)

    Chein, Jason; Albert, Dustin; O'Brien, Lia; Uckert, Kaitlyn; Steinberg, Laurence

    2011-01-01

    The presence of peers increases risk taking among adolescents but not adults. We posited that the presence of peers may promote adolescent risk taking by sensitizing brain regions associated with the anticipation of potential rewards. Using fMRI, we measured brain activity in adolescents, young adults, and adults as they made decisions in a…

  16. Regional brain activation supporting cognitive control in the context of reward is associated with treated adolescents’ marijuana problem severity at follow-up: A preliminary study

    Directory of Open Access Journals (Sweden)

    Tammy Chung

    2015-12-01

    Full Text Available This preliminary study examined the extent to which regional brain activation during a reward cue antisaccade (AS task was associated with 6-month treatment outcome in adolescent substance users. Antisaccade performance provides a sensitive measure of executive function and cognitive control, and generally improves with reward cues. We hypothesized that when preparing to execute an AS, greater activation in regions associated with cognitive and oculomotor control supporting AS, particularly during reward cue trials, would be associated with lower substance use severity at 6-month follow-up. Adolescents (n = 14, ages 14–18 recruited from community-based outpatient treatment completed an fMRI reward cue AS task (reward and neutral conditions, and provided follow-up data. Results indicated that AS errors decreased in reward, compared to neutral, trials. AS behavioral performance, however, was not associated with treatment outcome. As hypothesized, activation in regions of interest (ROIs associated with cognitive (e.g., ventrolateral prefrontal cortex and oculomotor control (e.g., supplementary eye field during reward trials were inversely correlated with marijuana problem severity at 6-months. ROI activation during neutral trials was not associated with outcomes. Results support the role of motivational (reward cue factors to enhance cognitive control processes, and suggest a potential brain-based correlate of youth treatment outcome.

  17. Neural networks involved in adolescent reward processing: An activation likelihood estimation meta-analysis of functional neuroimaging studies.

    Science.gov (United States)

    Silverman, Merav H; Jedd, Kelly; Luciana, Monica

    2015-11-15

    Behavioral responses to, and the neural processing of, rewards change dramatically during adolescence and may contribute to observed increases in risk-taking during this developmental period. Functional MRI (fMRI) studies suggest differences between adolescents and adults in neural activation during reward processing, but findings are contradictory, and effects have been found in non-predicted directions. The current study uses an activation likelihood estimation (ALE) approach for quantitative meta-analysis of functional neuroimaging studies to: (1) confirm the network of brain regions involved in adolescents' reward processing, (2) identify regions involved in specific stages (anticipation, outcome) and valence (positive, negative) of reward processing, and (3) identify differences in activation likelihood between adolescent and adult reward-related brain activation. Results reveal a subcortical network of brain regions involved in adolescent reward processing similar to that found in adults with major hubs including the ventral and dorsal striatum, insula, and posterior cingulate cortex (PCC). Contrast analyses find that adolescents exhibit greater likelihood of activation in the insula while processing anticipation relative to outcome and greater likelihood of activation in the putamen and amygdala during outcome relative to anticipation. While processing positive compared to negative valence, adolescents show increased likelihood for activation in the posterior cingulate cortex (PCC) and ventral striatum. Contrasting adolescent reward processing with the existing ALE of adult reward processing reveals increased likelihood for activation in limbic, frontolimbic, and striatal regions in adolescents compared with adults. Unlike adolescents, adults also activate executive control regions of the frontal and parietal lobes. These findings support hypothesized elevations in motivated activity during adolescence.

  18. Reduced reward processing in the brains of Parkinsonian patients

    NARCIS (Netherlands)

    Kunig, G; Leenders, KL; Martin-Solch, C; Missimer, J; Magyar, S; Schultz, W

    2000-01-01

    Regional cerebral blood flow (rCBF) in healthy controls and non-demented, non-depressed Parkinsonian patients was measured using H(2)(15)0 PET while subjects performed a prelearned pattern recognition task with delayed response. To investigate differences between the two groups in response to reward

  19. Processing of primary and secondary rewards: a quantitative meta-analysis and review of human functional neuroimaging studies

    NARCIS (Netherlands)

    Sescousse, G.T.; Caldu, X.; Segura, B.; Dreher, J.C.

    2013-01-01

    One fundamental question concerning brain reward mechanisms is to determine how reward-related activity is influenced by the nature of rewards. Here, we review the neuroimaging literature and explicitly assess to what extent the representations of primary and secondary rewards overlap in the human b

  20. Brain structural correlates of reward sensitivity and impulsivity in adolescents with normal and excess weight.

    Directory of Open Access Journals (Sweden)

    Laura Moreno-López

    Full Text Available INTRODUCTION: Neuroscience evidence suggests that adolescent obesity is linked to brain dysfunctions associated with enhanced reward and somatosensory processing and reduced impulse control during food processing. Comparatively less is known about the role of more stable brain structural measures and their link to personality traits and neuropsychological factors on the presentation of adolescent obesity. Here we aimed to investigate regional brain anatomy in adolescents with excess weight vs. lean controls. We also aimed to contrast the associations between brain structure and personality and cognitive measures in both groups. METHODS: Fifty-two adolescents (16 with normal weight and 36 with excess weight were scanned using magnetic resonance imaging and completed the Sensitivity to Punishment and Sensitivity to Reward Questionnaire (SPSRQ, the UPPS-P scale, and the Stroop task. Voxel-based morphometry (VBM was used to assess possible between-group differences in regional gray matter (GM and to measure the putative differences in the way reward and punishment sensitivity, impulsivity and inhibitory control relate to regional GM volumes, which were analyzed using both region of interest (ROI and whole brain analyses. The ROIs included areas involved in reward/somatosensory processing (striatum, somatosensory cortices and motivation/impulse control (hippocampus, prefrontal cortex. RESULTS: Excess weight adolescents showed increased GM volume in the right hippocampus. Voxel-wise volumes of the second somatosensory cortex (SII were correlated with reward sensitivity and positive urgency in lean controls, but this association was missed in excess weight adolescents. Moreover, Stroop performance correlated with dorsolateral prefrontal cortex volumes in controls but not in excess weight adolescents. CONCLUSION: Adolescents with excess weight have structural abnormalities in brain regions associated with somatosensory processing and motivation.

  1. Reward Contingencies Improve Goal-Directed Behavior by Enhancing Posterior Brain Attentional Regions and Increasing Corticostriatal Connectivity in Cocaine Addicts

    Science.gov (United States)

    Rosell-Negre, Patricia; Bustamante, Juan-Carlos; Fuentes-Claramonte, Paola; Costumero, Víctor; Llopis-Llacer, Juan-José; Barrós-Loscertales, Alfonso

    2016-01-01

    The dopaminergic system provides the basis for the interaction between motivation and cognition. It is triggered by the possibility of obtaining rewards to initiate the neurobehavioral adaptations necessary to achieve them by directing the information from motivational circuits to cognitive and action circuits. In drug addiction, the altered dopamine (DA) modulation of the meso-cortico-limbic reward circuitry, such as the prefrontal cortex (PFC), underlies the disproportionate motivational value of drug use at the expense of other non-drug reinforcers and the user’s loss of control over his/her drug intake. We examine how the magnitude of the reward affects goal-directed processes in healthy control (HC) subjects and abstinent cocaine dependent (ACD) patients by using functional magnetic resonance imaging (fMRI) during a counting Stroop task with blocked levels of monetary incentives of different magnitudes (€0, €0.01, €0.5, €1 or €1.5). Our results showed that increasing reward magnitude enhances (1) performance facilitation in both groups; (2) left dorsolateral prefrontal cortex (DLPFC) activity in HC and left superior occipital cortex activity in ACD; and (3) left DLPFC and left putamen connectivity in ACD compared to HC. Moreover, we observed that (4) dorsal striatal and pallidum activity was associated with craving and addiction severity during the parametric increases in the monetary reward. In conclusion, the brain response to gradients in monetary value was different in HC and ACD, but both groups showed improved task performance due to the possibility of obtaining greater monetary rewards. PMID:27907134

  2. Atypical Brain Responses to Reward Cues in Autism as Revealed by Event-Related Potentials

    Science.gov (United States)

    Kohls, Gregor; Peltzer, Judith; Schulte-Ruther, Martin; Kamp-Becker, Inge; Remschmidt, Helmut; Herpertz-Dahlmann, Beate; Konrad, Kerstin

    2011-01-01

    Social motivation deficit theories suggest that children with autism do not properly anticipate and appreciate the pleasure of social stimuli. In this study, we investigated event-related brain potentials evoked by cues that triggered social versus monetary reward anticipation in children with autism. Children with autism showed attenuated P3…

  3. Uncertainty, reward, and attention in the Bayesian brain

    DEFF Research Database (Denmark)

    Whiteley, Louise Emma

    2008-01-01

    The ‘Bayesian Coding Hypothesis’ formalises the classic Helmholtzian picture of perception as inverse inference, stating that the brain uses Bayes’ rule to compute posterior belief distributions over states of the world. There is much behavioural evidence that human observers can behave Bayes...... in the focus of attention. When faced instead with a complex scene, the brain can’t be Bayes-optimal everywhere. We suggest that a general limitation on the representation of complex posteriors causes the brain to make approximations, which are then locally re¿ned by attention. This framework extends ideas...... of attention as Bayesian prior, and uni¿es apparently disparate attentional ‘bottlenecks’. We present simulations of three key paradigms, and discuss how such modelling could be extended to more detailed, neurally inspired settings. Broadening the Bayesian picture of perception and strengthening its connection...

  4. Obesity is associated with high serotonin 4 receptor availability in the brain reward circuitry

    DEFF Research Database (Denmark)

    Haahr, M. E.; Rasmussen, Peter Mondrup; Madsen, K.;

    2012-01-01

    The neurobiology underlying obesity is not fully understood. The neurotransmitter serotonin (5-HT) is established as a satiety-generating signal, but its rewarding role in feeding is less well elucidated. From animal experiments there is now evidence that the 5-HT4 receptor (5-HT4R) is involved...... in food intake, and that pharmacological or genetic manipulation of the receptor in reward-related brain areas alters food intake.Here, we used positron emission tomography in humans to examine the association between cerebral 5-HT4Rs and common obesity.We found in humans a strong positive association......'s food intake. They also suggest that pharmacological stimulation of the cerebral 5-HT4R may reduce reward-related overeating in humans....

  5. Lutein and Brain Function

    Directory of Open Access Journals (Sweden)

    John W. Erdman

    2015-10-01

    Full Text Available Lutein is one of the most prevalent carotenoids in nature and in the human diet. Together with zeaxanthin, it is highly concentrated as macular pigment in the foveal retina of primates, attenuating blue light exposure, providing protection from photo-oxidation and enhancing visual performance. Recently, interest in lutein has expanded beyond the retina to its possible contributions to brain development and function. Only primates accumulate lutein within the brain, but little is known about its distribution or physiological role. Our team has begun to utilize the rhesus macaque (Macaca mulatta model to study the uptake and bio-localization of lutein in the brain. Our overall goal has been to assess the association of lutein localization with brain function. In this review, we will first cover the evolution of the non-human primate model for lutein and brain studies, discuss prior association studies of lutein with retina and brain function, and review approaches that can be used to localize brain lutein. We also describe our approach to the biosynthesis of 13C-lutein, which will allow investigation of lutein flux, localization, metabolism and pharmacokinetics. Lastly, we describe potential future research opportunities.

  6. Operant behavior to obtain palatable food modifies ERK activity in the brain reward circuit

    OpenAIRE

    Guegan, Thomas, 1983-; Cutando, Laura; Gangarossa, Giuseppe; Santini, Emanuela; Fisone, Gilberto; Martínez, Albert; Valjent, Emmanuel; Maldonado, Rafael; Martín Sánchez, Miquel, 1971-

    2013-01-01

    Food palatability produces behavioral modifications that resemble those induced by drugs of abuse. Palatability-induced behavioral changes require both, the activation of the endogenous cannabinoid system, and changes in structural plasticity in neurons of the brain reward pathway. The ERK intracellular pathway is activated by CB1 receptors (CB1-R) and plays a crucial role in neuroplasticity. We investigated the activation of the ERK signaling cascade in the mesocorticolimbic system induced b...

  7. Operant behavior to obtain palatable food modifies neuronal plasticity in the brain reward circuit

    OpenAIRE

    Guegan, Thomas, 1983-; Cutando, Laura; Ayuso, Eduard; Santini, Emanuela; Fisone, Gilberto; Bosch, Fatima; Martínez, Albert; Valjent, Emmanuel; Maldonado, Rafael; Martín Sánchez, Miquel, 1971-

    2013-01-01

    Palatability enhances food intake by hedonic mechanisms that prevail over caloric necessities. Different studies have demonstrated the role of endogenous cannabinoids in the mesocorticolimbic system in controlling food hedonic value and consumption. We hypothesize that the endogenous cannabinoid system could also be involved in the development of food-induced behavioral alterations, such as food-seeking and binge-eating, by a mechanism that requires neuroplastic changes in the brain reward pa...

  8. Reward optimization in the primate brain: a probabilistic model of decision making under uncertainty.

    Directory of Open Access Journals (Sweden)

    Yanping Huang

    Full Text Available A key problem in neuroscience is understanding how the brain makes decisions under uncertainty. Important insights have been gained using tasks such as the random dots motion discrimination task in which the subject makes decisions based on noisy stimuli. A descriptive model known as the drift diffusion model has previously been used to explain psychometric and reaction time data from such tasks but to fully explain the data, one is forced to make ad-hoc assumptions such as a time-dependent collapsing decision boundary. We show that such assumptions are unnecessary when decision making is viewed within the framework of partially observable Markov decision processes (POMDPs. We propose an alternative model for decision making based on POMDPs. We show that the motion discrimination task reduces to the problems of (1 computing beliefs (posterior distributions over the unknown direction and motion strength from noisy observations in a bayesian manner, and (2 selecting actions based on these beliefs to maximize the expected sum of future rewards. The resulting optimal policy (belief-to-action mapping is shown to be equivalent to a collapsing decision threshold that governs the switch from evidence accumulation to a discrimination decision. We show that the model accounts for both accuracy and reaction time as a function of stimulus strength as well as different speed-accuracy conditions in the random dots task.

  9. Is avoiding an aversive outcome rewarding? Neural substrates of avoidance learning in the human brain.

    Science.gov (United States)

    Kim, Hackjin; Shimojo, Shinsuke; O'Doherty, John P

    2006-07-01

    Avoidance learning poses a challenge for reinforcement-based theories of instrumental conditioning, because once an aversive outcome is successfully avoided an individual may no longer experience extrinsic reinforcement for their behavior. One possible account for this is to propose that avoiding an aversive outcome is in itself a reward, and thus avoidance behavior is positively reinforced on each trial when the aversive outcome is successfully avoided. In the present study we aimed to test this possibility by determining whether avoidance of an aversive outcome recruits the same neural circuitry as that elicited by a reward itself. We scanned 16 human participants with functional MRI while they performed an instrumental choice task, in which on each trial they chose from one of two actions in order to either win money or else avoid losing money. Neural activity in a region previously implicated in encoding stimulus reward value, the medial orbitofrontal cortex, was found to increase, not only following receipt of reward, but also following successful avoidance of an aversive outcome. This neural signal may itself act as an intrinsic reward, thereby serving to reinforce actions during instrumental avoidance.

  10. Reward Sensitivity Modulates Brain Activity in the Prefrontal Cortex, ACC and Striatum during Task Switching

    Science.gov (United States)

    Fuentes-Claramonte, Paola; Ávila, César; Rodríguez-Pujadas, Aina; Ventura-Campos, Noelia; Bustamante, Juan C.; Costumero, Víctor; Rosell-Negre, Patricia; Barrós-Loscertales, Alfonso

    2015-01-01

    Current perspectives on cognitive control acknowledge that individual differences in motivational dispositions may modulate cognitive processes in the absence of reward contingencies. This work aimed to study the relationship between individual differences in Behavioral Activation System (BAS) sensitivity and the neural underpinnings involved in processing a switching cue in a task-switching paradigm. BAS sensitivity was hypothesized to modulate brain activity in frontal regions, ACC and the striatum. Twenty-eight healthy participants underwent fMRI while performing a switching task, which elicited activity in fronto-striatal regions during the processing of the switch cue. BAS sensitivity was negatively associated with activity in the lateral prefrontal cortex, anterior cingulate cortex and the ventral striatum. Combined with previous results, our data indicate that BAS sensitivity modulates the neurocognitive processes involved in task switching in a complex manner depending on task demands. Therefore, individual differences in motivational dispositions may influence cognitive processing in the absence of reward contingencies. PMID:25875640

  11. Altered function of ventral striatum during reward-based decision making in old age

    Directory of Open Access Journals (Sweden)

    Thomas Mell

    2009-10-01

    Full Text Available Normal aging is associated with a decline in different cognitive domains and local structural atrophy as well as decreases in dopamine concentration and receptor density. To date, it is largely unknown how these reductions in dopaminergic neurotransmission affect human brain regions responsible for reward-based decision making in older adults. Using a learning criterion in a probabilistic object reversal task, we found a learning stage by age interaction in the dorsolateral prefrontal cortex (dlPFC during decision making. While young adults recruited the dlPFC in an early stage of learning reward associations, older adults recruited the dlPFC when reward associations had already been learned. Furthermore, we found a reduced change in ventral striatal BOLD signal in older as compared to younger adults in response to high probability rewards. Our data are in line with behavioral evidence that older adults show altered stimulus reward learning and support the view of an altered fronto-striatal interaction during reward-based decision making in old age, which contributes to prolonged learning of reward associations.

  12. Altered brain activity during reward anticipation in pathological gambling and obsessive-compulsive disorder.

    Directory of Open Access Journals (Sweden)

    Jung-Seok Choi

    Full Text Available BACKGROUND: Pathological gambling (PG and obsessive-compulsive disorder (OCD are conceptualized as a behavioral addiction, with a dependency on repetitive gambling behavior and rewarding effects following compulsive behavior, respectively. However, no neuroimaging studies to date have examined reward circuitry during the anticipation phase of reward in PG compared with in OCD while considering repetitive gambling and compulsion as addictive behaviors. METHODS/PRINCIPAL FINDINGS: To elucidate the neural activities specific to the anticipation phase of reward, we performed event-related functional magnetic resonance imaging (fMRI in young adults with PG and compared them with those in patients with OCD and healthy controls. Fifteen male patients with PG, 13 patients with OCD, and 15 healthy controls, group-matched for age, gender, and IQ, participated in a monetary incentive delay task during fMRI scanning. Neural activation in the ventromedial caudate nucleus during anticipation of both gain and loss decreased in patients with PG compared with that in patients with OCD and healthy controls. Additionally, reduced activation in the anterior insula during anticipation of loss was observed in patients with PG compared with that in patients with OCD which was intermediate between that in OCD and healthy controls (healthy controls < PG < OCD, and a significant positive correlation between activity in the anterior insula and South Oaks Gambling Screen score was found in patients with PG. CONCLUSIONS: Decreased neural activity in the ventromedial caudate nucleus during anticipation may be a specific neurobiological feature for the pathophysiology of PG, distinguishing it from OCD and healthy controls. Correlation of anterior insular activity during loss anticipation with PG symptoms suggests that patients with PG fit the features of OCD associated with harm avoidance as PG symptoms deteriorate. Our findings have identified functional disparities and

  13. Disrupted Brain Circuitry for Pain-Related Reward/Punishment in Fibromyalgia

    Science.gov (United States)

    Loggia, Marco L.; Berna, Chantal; Kim, Jieun; Cahalan, Christine M.; Gollub, Randy L.; Wasan, Ajay D.; Harris, Richard E.; Edwards, Robert R.; Napadow, Vitaly

    2015-01-01

    Objective While patients suffering from fibromyalgia (FM) are known to exhibit hyperalgesia, the central mechanisms contributing to this altered pain processing are not fully understood. In this study we investigate potential dysregulation of the neural circuitry underlying cognitive and hedonic aspects of the subjective experience of pain such as anticipation of pain and of pain relief. Methods FMRI was performed on 31 FM patients and 14 controls while they received cuff pressure pain stimuli on their leg, calibrated to elicit a pain rating of ∼50/100. During the scan, subjects also received visual cues informing them of impending pain onset (pain anticipation) and pain offset (relief anticipation). Results Patients exhibited less robust activations during both anticipation of pain and anticipation of relief within regions commonly thought to be involved in sensory, affective, cognitive and pain-modulatory processes. In healthy controls, direct searches and region-of-interest analyses in the ventral tegmental area (VTA) revealed a pattern of activity compatible with the encoding of punishment: activation during pain anticipation and pain stimulation, but deactivation during relief anticipation. In FM patients, however, VTA activity during pain and anticipation (of both pain and relief) periods was dramatically reduced or abolished. Conclusion FM patients exhibit disrupted brain responses to reward/punishment. The VTA is a source for reward-linked dopaminergic/GABAergic neurotransmission in the brain and our observations are compatible with reports of altered dopaminergic/GABAergic neurotransmission in FM. Reduced reward/punishment signaling in FM may relate to the augmented central processing of pain and reduced efficacy of opioid treatments in these patients. PMID:24449585

  14. DeltaFosB in brain reward circuits mediates resilience to stress and antidepressant responses.

    Science.gov (United States)

    Vialou, Vincent; Robison, Alfred J; Laplant, Quincey C; Covington, Herbert E; Dietz, David M; Ohnishi, Yoshinori N; Mouzon, Ezekiell; Rush, Augustus J; Watts, Emily L; Wallace, Deanna L; Iñiguez, Sergio D; Ohnishi, Yoko H; Steiner, Michel A; Warren, Brandon L; Krishnan, Vaishnav; Bolaños, Carlos A; Neve, Rachael L; Ghose, Subroto; Berton, Olivier; Tamminga, Carol A; Nestler, Eric J

    2010-06-01

    In contrast with the many studies of stress effects on the brain, relatively little is known about the molecular mechanisms of resilience, the ability of some individuals to escape the deleterious effects of stress. We found that the transcription factor DeltaFosB mediates an essential mechanism of resilience in mice. Induction of DeltaFosB in the nucleus accumbens, an important brain reward-associated region, in response to chronic social defeat stress was both necessary and sufficient for resilience. DeltaFosB induction was also required for the standard antidepressant fluoxetine to reverse behavioral pathology induced by social defeat. DeltaFosB produced these effects through induction of the GluR2 AMPA glutamate receptor subunit, which decreased the responsiveness of nucleus accumbens neurons to glutamate, and through other synaptic proteins. Together, these findings establish a previously unknown molecular pathway underlying both resilience and antidepressant action.

  15. Cognition and brain functional aging

    Directory of Open Access Journals (Sweden)

    Hui-jie LI

    2014-03-01

    Full Text Available China has the largest population of elderly adults. Meanwhile, it is one of the countries showing fastest aging speed in the world. Aging processing is always companied with a series of brain structural and functional changes, which result in the decline of processing speed, working memory, long-term memory and executive function, etc. The studies based on functional magnetic resonance imaging (fMRI found certain aging effects on brain function activation, spontaneous activity and functional connectivity in old people. However, few studies have explored the brain functional curve during the aging process while most previous studies explored the differences in the brain function between young people and old people. Delineation of the human brain functional aging curve will promote the understanding of brain aging mechanisms and support the normal aging monitoring and early detection of abnormal aging changes. doi: 10.3969/j.issn.1672-6731.2014.03.005

  16. Trisomy of the G protein-coupled K+ channel gene, Kcnj6, affects reward mechanisms, cognitive functions, and synaptic plasticity in mice

    OpenAIRE

    Cooper, Ayelet; Grigoryan, Gayane; Guy-David, Liora; Tsoory, Michael M; Chen, Alon; Reuveny, Eitan

    2012-01-01

    G protein-activated inwardly rectifying K+ channels (GIRK) generate slow inhibitory postsynaptic potentials in the brain via Gi/o protein-coupled receptors. GIRK2, a GIRK subunit, is widely abundant in the brain and has been implicated in various functions and pathologies, such as learning and memory, reward, motor coordination, and Down syndrome. Down syndrome, the most prevalent cause of mental retardation, results from the presence of an extra maternal chromosome 21 (trisomy 21), which com...

  17. Fat/carbohydrate ratio but not energy density determines snack food intake and activates brain reward areas.

    Science.gov (United States)

    Hoch, Tobias; Kreitz, Silke; Gaffling, Simone; Pischetsrieder, Monika; Hess, Andreas

    2015-05-14

    The snack food potato chips induces food intake in ad libitum fed rats, which is associated with modulation of the brain reward system and other circuits. Here, we show that food intake in satiated rats is triggered by an optimal fat/carbohydrate ratio. Like potato chips, an isocaloric fat/carbohydrate mixture influenced whole brain activity pattern of rats, affecting circuits related e.g. to reward/addiction, but the number of modulated areas and the extent of modulation was lower compared to the snack food itself.

  18. Fat/carbohydrate ratio but not energy density determines snack food intake and activates brain reward areas

    OpenAIRE

    Hoch, Tobias; Kreitz, Silke; Gaffling, Simone; Pischetsrieder, Monika; Hess, Andreas

    2015-01-01

    The snack food potato chips induces food intake in ad libitum fed rats, which is associated with modulation of the brain reward system and other circuits. Here, we show that food intake in satiated rats is triggered by an optimal fat/carbohydrate ratio. Like potato chips, an isocaloric fat/carbohydrate mixture influenced whole brain activity pattern of rats, affecting circuits related e.g. to reward/addiction, but the number of modulated areas and the extent of modulation was lower compared t...

  19. It's in the eye of the beholder: selective attention to drink properties during tasting influences brain activation in gustatory and reward regions.

    Science.gov (United States)

    van Rijn, Inge; de Graaf, Cees; Smeets, Paul A M

    2017-03-20

    Statements regarding pleasantness, taste intensity or caloric content on a food label may influence the attention consumers pay to such characteristics during consumption. There is little research on the effects of selective attention on taste perception and associated brain activation in regular drinks. The aim of this study was to investigate the effect of selective attention on hedonics, intensity and caloric content on brain responses during tasting drinks. Using functional MRI brain responses of 27 women were measured while they paid attention to the intensity, pleasantness or caloric content of fruit juice, tomato juice and water. Brain activation during tasting largely overlapped between the three selective attention conditions and was found in the rolandic operculum, insula and overlying frontal operculum, striatum, amygdala, thalamus, anterior cingulate cortex and middle orbitofrontal cortex (OFC). Brain activation was higher during selective attention to taste intensity compared to calories in the right middle OFC and during selective attention to pleasantness compared to intensity in the right putamen, right ACC and bilateral middle insula. Intensity ratings correlated with brain activation during selective attention to taste intensity in the anterior insula and lateral OFC. Our data suggest that not only the anterior insula but also the middle and lateral OFC are involved in evaluating taste intensity. Furthermore, selective attention to pleasantness engaged regions associated with food reward. Overall, our results indicate that selective attention to food properties can alter the activation of gustatory and reward regions. This may underlie effects of food labels on the consumption experience of consumers.

  20. Effects of reward sensitivity and regional brain volumes on substance use initiation in adolescence.

    Science.gov (United States)

    Urošević, Snežana; Collins, Paul; Muetzel, Ryan; Schissel, Ann; Lim, Kelvin O; Luciana, Monica

    2015-01-01

    This longitudinal study examines associations between baseline individual differences and developmental changes in reward [i.e. behavioral approach system (BAS)] sensitivity and relevant brain structures' volumes to prospective substance use initiation during adolescence. A community sample of adolescents ages 15-18 with no prior substance use was assessed for substance use initiation (i.e. initiation of regular alcohol use and/or any use of other substances) during a 2-year follow-up period and for alcohol use frequency in the last year of the follow-up. Longitudinal 'increases' in BAS sensitivity were associated with substance use initiation and increased alcohol use frequency during the follow-up. Moreover, adolescents with smaller left nucleus accumbens at baseline were more likely to initiate substance use during the follow-up period. This study provides support for the link between developmental increases in reward sensitivity and substance use initiation in adolescence. The study also emphasizes the potential importance of individual differences in volumes of subcortical regions and their structural development for substance use initiation during adolescence.

  1. Deep brain stimulation of the subthalamic nucleus improves reward-based decision-learning in Parkinson’s disease

    NARCIS (Netherlands)

    Wouwe, N.C. van; Ridderinkhof, K.R.; Wildenberg, W.P.M. van den; Band, G.P.H.; Abisogun, A.; Elias, W.J.; Frysinger, R.; Wylie, S.A.

    2011-01-01

    Recently, the subthalamic nucleus (STN) has been shown to be critically involved in decision-making, action selection, and motor control. Here we investigate the effect of deep brain stimulation (DBS) of the STN on reward-based decision-learning in patients diagnosed with Parkinson’s disease (PD). W

  2. Sugar overconsumption during adolescence selectively alters motivation and reward function in adult rats.

    Directory of Open Access Journals (Sweden)

    Leandro F Vendruscolo

    Full Text Available BACKGROUND: There has been a dramatic escalation in sugar intake in the last few decades, most strikingly observed in the adolescent population. Sugar overconsumption has been associated with several adverse health consequences, including obesity and diabetes. Very little is known, however, about the impact of sugar overconsumption on mental health in general, and on reward-related behavioral disorders in particular. This study examined in rats the effects of unlimited access to sucrose during adolescence on the motivation for natural and pharmacological rewards in adulthood. METHODOLOGY/PRINCIPAL FINDINGS: Adolescent rats had free access to 5% sucrose or water from postnatal day 30 to 46. The control group had access to water only. In adulthood, rats were tested for self-administration of saccharin (sweet, maltodextrin (non-sweet, and cocaine (a potent drug of abuse using fixed- and progressive-ratio schedules, and a concentration-response curve for each substance. Adult rats, exposed or not exposed to sucrose, were tested for saccharin self-administration later in life to verify the specificity of adolescence for the sugar effects. Sugar overconsumption during adolescence, but not during adulthood, reduced the subsequent motivation for saccharin and maltodextrin, but not cocaine. This selective decrease in motivation is more likely due to changes in brain reward processing than changes in gustatory perception. CONCLUSIONS/SIGNIFICANCE: Sugar overconsumption induces a developmental stage-specific chronic depression in reward processing that may contribute to an increase in the vulnerability to reward-related psychiatric disorders.

  3. Sarcosine attenuates toluene-induced motor incoordination, memory impairment, and hypothermia but not brain stimulation reward enhancement in mice

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Ming-Huan [Department of Pharmacology and Toxicology, Tzu Chi University, Hualien, Taiwan (China); Institute of Neuroscience, National Changchi University, Taipei, Taiwan (China); Chung, Shiang-Sheng [Department of Pharmacology and Toxicology, Tzu Chi University, Hualien, Taiwan (China); Department of Pharmacy, Yuli Veterans Hospital, Hualien, Taiwan (China); Stoker, Astrid K.; Markou, Athina [Department of Psychiatry, School of Medicine, University of California San Diego, La Jolla, CA (United States); Chen, Hwei-Hsien, E-mail: hwei@nhri.org.tw [Department of Pharmacology and Toxicology, Tzu Chi University, Hualien, Taiwan (China); Division of Mental Health and Addiction Medicine, Institute of Population Health Sciences, National Health Research Institutes, Zhunan, Miaoli County, Taiwan (China)

    2012-12-01

    Toluene, a widely used and commonly abused organic solvent, produces various behavioral disturbances, including motor incoordination and cognitive impairment. Toluene alters the function of a large number of receptors and ion channels. Blockade of N-methyl-D-aspartate (NMDA) receptors has been suggested to play a critical role in toluene-induced behavioral manifestations. The present study determined the effects of various toluene doses on motor coordination, recognition memory, body temperature, and intracranial self-stimulation (ICSS) thresholds in mice. Additionally, the effects of sarcosine on the behavioral and physiological effects induced by toluene were evaluated. Sarcosine may reverse toluene-induced behavioral manifestations by acting as an NMDA receptor co-agonist and by inhibiting the effects of the type I glycine transporter (GlyT1). Mice were treated with toluene alone or combined with sarcosine pretreatment and assessed for rotarod performance, object recognition memory, rectal temperature, and ICSS thresholds. Toluene dose-dependently induced motor incoordination, recognition memory impairment, and hypothermia and lowered ICSS thresholds. Sarcosine pretreatment reversed toluene-induced changes in rotarod performance, novel object recognition, and rectal temperature but not ICSS thresholds. These findings suggest that the sarcosine-induced potentiation of NMDA receptors may reverse motor incoordination, memory impairment, and hypothermia but not the enhancement of brain stimulation reward function associated with toluene exposure. Sarcosine may be a promising compound to prevent acute toluene intoxications by occupational or intentional exposure. -- Highlights: ► Toluene induces impairments in Rotarod test and novel object recognition test. ► Toluene lowers rectal temperature and ICSS thresholds in mice. ► Sarcosine reverses toluene-induced changes in motor, memory and body temperature. ► Sarcosine pretreatment does not affect toluene

  4. Function of the centromedial amygdala in reward devaluation and open-field activity.

    Science.gov (United States)

    Kawasaki, K; Glueck, A C; Annicchiarico, I; Papini, M R

    2015-09-10

    The present research aimed at determining the role played by the amygdala in reward devaluation using transient inactivation induced by lidocaine microinfusions into the centromedial region. Two situations involving reward devaluation were tested in rats: consummatory successive negative contrast (cSNC) and anticipatory negative contrast (ANC). In cSNC, rats exposed to a downshift from 32% to 4% sucrose consume less 4% sucrose than rats always exposed to 4% sucrose. Extensive evidence suggests that reward devaluation in the cSNC situation is accompanied by negative emotion. In ANC, rats consume less 4% sucrose when each session is closely followed by access to 32% sucrose rather than by 4% sucrose. Evidence suggests that reward devaluation in the ANC situation does not involve negative emotions; rather, ANC appears to involve Pavlovian anticipation of the higher value solution. To test the effects of lidocaine microinfusions in a situation known to induce negative emotion, but unrelated to reward devaluation, animals were also exposed to a lighted open field. Centromedial amygdala inactivation reduced the cSNC effect and increased exploratory behavior in the open field, both effects consistent with a reduction in negative emotional state. However, no detectable effects of amygdala inactivation were observed in the ANC situation. These results suggest that, first, the function of the amygdala is not unique to reward devaluation and, second, it is concerned with tagging the devaluation experience with aversive valence.

  5. Relation of reward from food intake and anticipated food intake to obesity: a functional magnetic resonance imaging study.

    Science.gov (United States)

    Stice, Eric; Spoor, Sonja; Bohon, Cara; Veldhuizen, Marga G; Small, Dana M

    2008-11-01

    The authors tested the hypothesis that obese individuals experience greater reward from food consumption (consummatory food reward) and anticipated consumption (anticipatory food reward) than lean individuals using functional magnetic resonance imaging (fMRI) with 33 adolescent girls (mean age = 15.7, SD = 0.9). Obese relative to lean adolescent girls showed greater activation bilaterally in the gustatory cortex (anterior and mid insula, frontal operculum) and in somatosensory regions (parietal operculum and Rolandic operculum) in response to anticipated intake of chocolate milkshake (vs. a tasteless solution) and to actual consumption of milkshake (vs. a tasteless solution); these brain regions encode the sensory and hedonic aspects of food. However, obese relative to lean adolescent girls also showed decreased activation in the caudate nucleus in response to consumption of milkshake versus a tasteless solution, potentially because they have reduced dopamine receptor availability. Results suggest that individuals who show greater activation in the gustatory cortex and somatosensory regions in response to anticipation and consumption of food, but who show weaker activation in the striatum during food intake, may be at risk for overeating and consequent weight gain.

  6. Operant behavior to obtain palatable food modifies ERK activity in the brain reward circuit.

    Science.gov (United States)

    Guegan, Thomas; Cutando, Laura; Gangarossa, Giuseppe; Santini, Emanuela; Fisone, Gilberto; Martinez, Albert; Valjent, Emmanuel; Maldonado, Rafael; Martin, Miquel

    2013-03-01

    Food palatability produces behavioral modifications that resemble those induced by drugs of abuse. Palatability-induced behavioral changes require both, the activation of the endogenous cannabinoid system, and changes in structural plasticity in neurons of the brain reward pathway. The ERK intracellular pathway is activated by CB1 receptors (CB1-R) and plays a crucial role in neuroplasticity. We investigated the activation of the ERK signaling cascade in the mesocorticolimbic system induced by operant training to obtain highly palatable isocaloric food and the involvement of the CB1-R in these responses. Using immunofluorescence techniques, we analyzed changes in ERK intracellular pathway activation in the mesocorticolimbic system of wild-type and CB1 knockout mice (CB1-/-) trained on an operant paradigm to obtain standard, highly caloric or highly palatable isocaloric food. Operant training for highly palatable isocaloric food, but not for standard or highly caloric food, produced a robust activation of the ERK signaling cascade in the same brain areas where this training modified structural plasticity. These changes induced by the operant training were absent in CB1-/-. We can conclude that the activation of the ERK pathway is associated to the neuroplasticity induced by operant training for highly palatable isocaloric food and might be involved in CB1-R mediated alterations in behavior and structural plasticity.

  7. GABRB1 Single Nucleotide Polymorphism Associated with Altered Brain Responses (but not Performance) during Measures of Impulsivity and Reward Sensitivity in Human Adolescents

    Science.gov (United States)

    Duka, Theodora; Nikolaou, Kyriaki; King, Sarah L.; Banaschewski, Tobias; Bokde, Arun L. W.; Büchel, Christian; Carvalho, Fabiana M.; Conrod, Patricia J.; Flor, Herta; Gallinat, Jürgen; Garavan, Hugh; Heinz, Andreas; Jia, Tianye; Gowland, Penny; Martinot, Jean-Luc; Paus, Tomáš; Rietschel, Marcella; Robbins, Trevor W.; Smolka, Michael; Schumann, Gunter; Stephens, David N.

    2017-01-01

    Variations in genes encoding several GABAA receptors have been associated with human drug and alcohol abuse. Among these, a number of human studies have suggested an association between GABRB1, the gene encoding GABAA receptor β1 subunits, with Alcohol dependence (AD), both on its own and comorbid with other substance dependence and psychiatric illnesses. In the present study, we hypothesized that the GABRB1 genetically-associated increased risk for developing alcoholism may be associated with impaired behavioral control and altered sensitivity to reward, as a consequence of altered brain function. Exploiting the IMAGEN database (Schumann et al., 2010), we explored in a human adolescent population whether possession of the minor (T) variant of the single nucleotide polymorphism (SNP) rs2044081 is associated with performance of tasks measuring aspects of impulsivity, and reward sensitivity that are implicated in drug and alcohol abuse. Allelic variation did not associate with altered performance in either a stop-signal task (SST), measuring one aspect of impulsivity, or a monetary incentive delay (MID) task assessing reward anticipation. However, increased functional magnetic resonance imaging (fMRI) blood-oxygen-level dependent (BOLD) response in the right hemisphere inferior frontal gyrus (IFG), left hemisphere caudate/insula and left hemisphere inferior temporal gyrus (ITG) during MID performance was higher in the minor (T) allelic group. In contrast, during SST performance, the BOLD response found in the right hemisphere supramarginal gyrus, right hemisphere lingual and left hemisphere inferior parietal gyrus indicated reduced responses in the minor genotype. We suggest that β1-containing GABAA receptors may play a role in excitability of brain regions important in controlling reward-related behavior, which may contribute to susceptibility to addictive behavior. PMID:28261068

  8. Neural coding of basic reward terms of animal learning theory, game theory, microeconomics and behavioural ecology.

    Science.gov (United States)

    Schultz, Wolfram

    2004-04-01

    Neurons in a small number of brain structures detect rewards and reward-predicting stimuli and are active during the expectation of predictable food and liquid rewards. These neurons code the reward information according to basic terms of various behavioural theories that seek to explain reward-directed learning, approach behaviour and decision-making. The involved brain structures include groups of dopamine neurons, the striatum including the nucleus accumbens, the orbitofrontal cortex and the amygdala. The reward information is fed to brain structures involved in decision-making and organisation of behaviour, such as the dorsolateral prefrontal cortex and possibly the parietal cortex. The neural coding of basic reward terms derived from formal theories puts the neurophysiological investigation of reward mechanisms on firm conceptual grounds and provides neural correlates for the function of rewards in learning, approach behaviour and decision-making.

  9. Neural processing of reward in adolescent rodents

    Directory of Open Access Journals (Sweden)

    Nicholas W. Simon

    2015-02-01

    Full Text Available Immaturities in adolescent reward processing are thought to contribute to poor decision making and increased susceptibility to develop addictive and psychiatric disorders. Very little is known; however, about how the adolescent brain processes reward. The current mechanistic theories of reward processing are derived from adult models. Here we review recent research focused on understanding of how the adolescent brain responds to rewards and reward-associated events. A critical aspect of this work is that age-related differences are evident in neuronal processing of reward-related events across multiple brain regions even when adolescent rats demonstrate behavior similar to adults. These include differences in reward processing between adolescent and adult rats in orbitofrontal cortex and dorsal striatum. Surprisingly, minimal age related differences are observed in ventral striatum, which has been a focal point of developmental studies. We go on to discuss the implications of these differences for behavioral traits affected in adolescence, such as impulsivity, risk-taking, and behavioral flexibility. Collectively, this work suggests that reward-evoked neural activity differs as a function of age and that regions such as the dorsal striatum that are not traditionally associated with affective processing in adults may be critical for reward processing and psychiatric vulnerability in adolescents.

  10. The impact of financial reward contingencies on cognitive function profiles in adult ADHD.

    Directory of Open Access Journals (Sweden)

    Ivo Marx

    Full Text Available OBJECTIVES: Although it is well established that cognitive performance in children with attention-deficit/hyperactivity disorder (ADHD is affected by reward and that key deficits associated with the disorder may thereby be attenuated or even compensated, this phenomenon in adults with ADHD has thus far not been addressed. Therefore, the aim of the present study was to examine the motivating effect of financial reward on task performance in adults with ADHD by focusing on the domains of executive functioning, attention, time perception, and delay aversion. METHODS: We examined male and female adults aged 18-40 years with ADHD (n = 38 along with a matched control group (n = 40 using six well-established experimental paradigms. RESULTS: Impaired performance in the ADHD group was observed for stop-signal omission errors, n-back accuracy, reaction time variability in the continuous performance task, and time reproduction accuracy, and reward normalized time reproduction accuracy. Furthermore, when rewarded, subjects with ADHD exhibited longer reaction times and fewer false positives in the continuous performance task, which suggests the use of strategies to prevent impulsivity errors. CONCLUSIONS: Taken together, our results support the existence of both cognitive and motivational mechanisms for the disorder, which is in line with current models of ADHD. Furthermore, our data suggest cognitive strategies of "stopping and thinking" as a possible underlying mechanism for task improvement that seems to be mediated by reward, which highlights the importance of the interaction between motivation and cognition in adult ADHD.

  11. Rewards teach visual selective attention.

    Science.gov (United States)

    Chelazzi, Leonardo; Perlato, Andrea; Santandrea, Elisa; Della Libera, Chiara

    2013-06-07

    Visual selective attention is the brain function that modulates ongoing processing of retinal input in order for selected representations to gain privileged access to perceptual awareness and guide behavior. Enhanced analysis of currently relevant or otherwise salient information is often accompanied by suppressed processing of the less relevant or salient input. Recent findings indicate that rewards exert a powerful influence on the deployment of visual selective attention. Such influence takes different forms depending on the specific protocol adopted in the given study. In some cases, the prospect of earning a larger reward in relation to a specific stimulus or location biases attention accordingly in order to maximize overall gain. This is mediated by an effect of reward acting as a type of incentive motivation for the strategic control of attention. In contrast, reward delivery can directly alter the processing of specific stimuli by increasing their attentional priority, and this can be measured even when rewards are no longer involved, reflecting a form of reward-mediated attentional learning. As a further development, recent work demonstrates that rewards can affect attentional learning in dissociable ways depending on whether rewards are perceived as feedback on performance or instead are registered as random-like events occurring during task performance. Specifically, it appears that visual selective attention is shaped by two distinct reward-related learning mechanisms: one requiring active monitoring of performance and outcome, and a second one detecting the sheer association between objects in the environment (whether attended or ignored) and the more-or-less rewarding events that accompany them. Overall this emerging literature demonstrates unequivocally that rewards "teach" visual selective attention so that processing resources will be allocated to objects, features and locations which are likely to optimize the organism's interaction with the

  12. Operant behavior to obtain palatable food modifies neuronal plasticity in the brain reward circuit.

    Science.gov (United States)

    Guegan, Thomas; Cutando, Laura; Ayuso, Eduard; Santini, Emanuela; Fisone, Gilberto; Bosch, Fatima; Martinez, Albert; Valjent, Emmanuel; Maldonado, Rafael; Martin, Miquel

    2013-02-01

    Palatability enhances food intake by hedonic mechanisms that prevail over caloric necessities. Different studies have demonstrated the role of endogenous cannabinoids in the mesocorticolimbic system in controlling food hedonic value and consumption. We hypothesize that the endogenous cannabinoid system could also be involved in the development of food-induced behavioral alterations, such as food-seeking and binge-eating, by a mechanism that requires neuroplastic changes in the brain reward pathway. For this purpose, we evaluated the role of the CB1 cannabinoid receptor (CB1-R) in the behavioral and neuroplastic changes induced by operant training for standard, highly caloric or highly palatable isocaloric food using different genetics, viral and pharmacological approaches. Neuroplasticity was evaluated by measuring changes in dendritic spine density in neurons previously labeled with the dye DiI. Only operant training to obtain highly palatable isocaloric food induced neuroplastic changes in neurons of the nucleus accumbens shell and prefrontal cortex that were associated to changes in food-seeking behavior. These behavioral and neuroplastic modifications induced by highly palatable isocaloric food were dependent on the activity of the CB1-R. Neuroplastic changes induced by highly palatable isocaloric food are similar to those produced by some drugs of abuse and may be crucial in the alteration of food-seeking behavior leading to overweight and obesity.

  13. Longitudinal Changes in Behavioral Approach System Sensitivity and Brain Structures Involved in Reward Processing during Adolescence

    Science.gov (United States)

    Urosevic, Snezana; Collins, Paul; Muetzel, Ryan; Lim, Kelvin; Luciana, Monica

    2012-01-01

    Adolescence is a period of radical normative changes and increased risk for substance use, mood disorders, and physical injury. Researchers have proposed that increases in reward sensitivity (i.e., sensitivity of the behavioral approach system [BAS]) and/or increases in reactivity to all emotional stimuli (i.e., reward and threat sensitivities)…

  14. Epigenetic programming of reward function in offspring: a role for maternal diet.

    Science.gov (United States)

    Grissom, Nicola; Bowman, Nicole; Reyes, Teresa M

    2014-02-01

    Early life development, through gestation and lactation, represents a timeframe of extreme vulnerability for the developing fetus in general, and for the central nervous system in particular. An adverse perinatal environment can have a lasting negative impact on brain development, increasing the risk for developmental disorders and broader psychopathologies. A major determinant of the fetal developmental environment is maternal diet. The present review summarizes the current literature regarding the effect of poor maternal perinatal nutrition on offspring brain development, with an emphasis on reward-related neural systems and behaviors. Epigenetic mechanisms represent a likely link between maternal diet and persistent changes in offspring brain development, and these mechanisms are presented and discussed within the context of perinatal maternal nutrition.

  15. Imbalanced functional link between reward circuits and the cognitive control system in patients with obsessive-compulsive disorder.

    Science.gov (United States)

    Xie, Chunming; Ma, Lisha; Jiang, Nan; Huang, Ruyan; Li, Li; Gong, Liang; He, Cancan; Xiao, Chaoyong; Liu, Wen; Xu, Shu; Zhang, Zhijun

    2016-08-23

    Altered reward processing and cognitive deficits are often observed in patients with obsessive-compulsive disorder (OCD); however, whether the imbalance in activity between reward circuits and the cognitive control (CC) system is associated with compulsive behavior remains unknown. Sixty-eight OCD patients and 33 cognitively normal (CN) healthy subjects participated in this resting-state functional magnetic resonance imaging study. Alterations in the functional connectivity between reward circuits and the CC system were quantitatively assessed and compared between the groups. A Granger causality analysis was used to determine the causal informational influence between and within reward circuits and the CC system across all subjects. OCD patients showed a dichotomous pattern of enhanced functional coupling in their reward circuits and a weakened functional coupling in their CC system when compared to CN subjects. Neural correlates of compulsive behavior were primarily located in the reward circuits and CC system in OCD patients. Importantly, the CC system exerted a reduced interregional causal influence over the reward system in OCD patients relative to its effect in CN subjects. The limitations of this study are that it was a cross-sectional study and the potential effects of environmental and genetic factors were not explored. OCD patients showed an imbalance in the functional link between reward circuits and the CC system at rest. This bias toward a loss of control may define a pathological state in which subjects are more vulnerable to engaging in compulsive behaviors.

  16. Functional Brain Imaging: A Comprehensive Survey

    CERN Document Server

    Sarraf, Saman

    2016-01-01

    Functional brain imaging allows measuring dynamic functionality in all brain regions. It is broadly used in clinical cognitive neuroscience as, well as in research. It will allow the observation of neural activities in the brain simultaneously. From the beginning when functional brain imaging was initiated by the mapping of brain functions proposed by phrenologists, many scientists were asking why we need to image brain functionality since we have already structural information. Simply, their important question was including a great answer. Functional information of the human brain would definitely complement structural information, helping to have a better understanding of what is happening in the brain. This paper, which could be useful to those who have an interest in functional brain imaging, such as engineers, will present a quick review of modalities used in functional brain imaging. We will concentrate on the most used techniques in functional imaging which are functional magnetic resonance imaging (fM...

  17. Natural reward experience alters AMPA and NMDA receptor distribution and function in the nucleus accumbens.

    Directory of Open Access Journals (Sweden)

    Kyle K Pitchers

    Full Text Available Natural reward and drugs of abuse converge upon the mesolimbic system which mediates motivation and reward behaviors. Drugs induce neural adaptations in this system, including transcriptional, morphological, and synaptic changes, which contribute to the development and expression of drug-related memories and addiction. Previously, it has been reported that sexual experience in male rats, a natural reward behavior, induces similar neuroplasticity in the mesolimbic system and affects natural reward and drug-related behavior. The current study determined whether sexual experience causes long-lasting changes in mating, or ionotropic glutamate receptor trafficking or function in the nucleus accumbens (NAc, following 3 different reward abstinence periods: 1 day, 1 week, or 1 month after final mating session. Male Sprague Dawley rats mated during 5 consecutive days (sexual experience or remained sexually naïve to serve as controls. Sexually experienced males displayed facilitation of initiation and performance of mating at each time point. Next, intracellular and membrane surface expression of N-methyl-D-aspartate (NMDA: NR1 subunit and α-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA: GluA1, GluA2 subunits receptors in the NAc was determined using a bis(sulfosuccinimidylsuberate (BS(3 protein cross-linking assay followed by Western Blot analysis. NR1 expression was increased at 1 day abstinence both at surface and intracellular, but decreased at surface at 1 week of abstinence. GluA2 was increased intracellularly at 1 week and increased at the surface after 1 month of abstinence. Finally, whole-cell patch clamp electrophysiological recordings determined reduced AMPA/NMDA ratio of synaptic currents in NAc shell neurons following stimulation of cortical afferents in sexually experienced males after all reward abstinence periods. Together, these data show that sexual experience causes long-term alterations in glutamate receptor expression and

  18. Gambling for self, friends, and antagonists: differential contributions of affective and social brain regions on adolescent reward processing.

    Science.gov (United States)

    Braams, Barbara R; Peters, Sabine; Peper, Jiska S; Güroğlu, Berna; Crone, Eveline A

    2014-10-15

    Adolescence is a time of increasing emotional arousal, sensation-seeking and risk-taking, especially in the context of peers. Recent neuroscientific studies have pinpointed to the role of the ventral striatum as a brain region which is particularly sensitive to reward, and to 'social brain' regions, such as the medial prefrontal cortex (mPFC), the precuneus, and the temporal parietal junction, as being particularly responsive to social contexts. However, no study to date has examined adolescents' sensitivity to reward across different social contexts. In this study we examined 249 participants between the ages 8 and 25, on a monetary reward-processing task. Participants could win or lose money for themselves, their best friend and a disliked peer. Winning for self resulted in a mid- to late adolescent specific peak in neural activation in the ventral striatum, whereas winning for a disliked peer resulted in a mid- to late adolescent specific peak in the mPFC. Our findings reveal that ventral striatum and mPFC hypersensitivity in adolescence is dependent on social context. Taken together, these results suggest that increased risk-taking and sensation seeking observed in adolescence might not be purely related to hyperactivity of the ventral striatum, but that these behaviors are probably strongly related to the social context in which they occur.

  19. Neural response to reward anticipation is modulated by Gray's impulsivity.

    Science.gov (United States)

    Hahn, Tim; Dresler, Thomas; Ehlis, Ann-Christine; Plichta, Michael M; Heinzel, Sebastian; Polak, Thomas; Lesch, Klaus-Peter; Breuer, Felix; Jakob, Peter M; Fallgatter, Andreas J

    2009-07-15

    According to the Reinforcement Sensitivity Theory (RST), Gray's dimension of impulsivity, reflecting human trait reward sensitivity, determines the extent to which stimuli activate the Behavioural Approach System (BAS). The potential neural underpinnings of the BAS, however, remain poorly understood. In the present study, we examined the association between Gray's impulsivity as defined by the RST and event-related fMRI BOLD-response to anticipation of reward in twenty healthy human subjects in brain regions previously associated with reward processing. Anticipation of reward during a Monetary Incentive Delay Task elicited activation in key components of the human reward circuitry such as the ventral striatum, the amygdala and the orbitofrontal cortex. Interindividual differences in Gray's impulsivity accounted for a significant amount of variance of the reward-related BOLD-response in the ventral striatum and the orbitofrontal cortex. Specifically, higher trait reward sensitivity was associated with increased activation in response to cues indicating potential reward. Extending previous evidence, here we show that variance in functional brain activation during anticipation of reward is attributed to interindividual differences regarding Gray's dimension of impulsivity. Thus, trait reward sensitivity contributes to the modulation of responsiveness in major components of the human reward system which thereby display a core property of the BAS. Generally, fostering our understanding of the neural underpinnings of the association of reward-related interindividual differences in affective traits might aid researchers in quest for custom-tailored treatments of psychiatric disorders, further disentangling the complex relationship between personality traits, emotion, and health.

  20. Increased functional connectivity between prefrontal cortex and reward system in pathological gambling.

    Directory of Open Access Journals (Sweden)

    Saskia Koehler

    Full Text Available Pathological gambling (PG shares clinical characteristics with substance-use disorders and is thus discussed as a behavioral addiction. Recent neuroimaging studies on PG report functional changes in prefrontal structures and the mesolimbic reward system. While an imbalance between these structures has been related to addictive behavior, whether their dysfunction in PG is reflected in the interaction between them remains unclear. We addressed this question using functional connectivity resting-state fMRI in male subjects with PG and controls. Seed-based functional connectivity was computed using two regions-of-interest, based on the results of a previous voxel-based morphometry study, located in the prefrontal cortex and the mesolimbic reward system (right middle frontal gyrus and right ventral striatum. PG patients demonstrated increased connectivity from the right middle frontal gyrus to the right striatum as compared to controls, which was also positively correlated with nonplanning aspect of impulsiveness, smoking and craving scores in the PG group. Moreover, PG patients demonstrated decreased connectivity from the right middle frontal gyrus to other prefrontal areas as compared to controls. The right ventral striatum demonstrated increased connectivity to the right superior and middle frontal gyrus and left cerebellum in PG patients as compared to controls. The increased connectivity to the cerebellum was positively correlated with smoking in the PG group. Our results provide further evidence for alterations in functional connectivity in PG with increased connectivity between prefrontal regions and the reward system, similar to connectivity changes reported in substance use disorder.

  1. Financial segment reporting in the function of building a motivation and rewarding system

    Directory of Open Access Journals (Sweden)

    Ljubica Gajic

    2010-07-01

    Full Text Available One of the main factors of a company’s business performance is complete mobility andorientation of the employees towards realizing common interests and goals of the company as awhole. Activities aimed at that goal are also related to building a motivation system in thecompany. One of the means of motivation policy is the system of incentive rewards, where theinformation input is the calculation of costs and business results of a company, relying oncomplete tracking of business processes, according to functions, fields and centres ofresponsibility for achieved success or failure. Profit, as the final financial product of thecompany’s activities, is basically the main activating force for all the employees. Their motivationhelps successful achievement of a company’s business policy and strategic development, througha functional system of measuring and evaluating results and adequate rewards.

  2. Cognitive control of drug craving inhibits brain reward regions in cocaine abusers

    Energy Technology Data Exchange (ETDEWEB)

    Volkow, N.D.; Fowler, J.; Wang, G.J.; Telang, F.; Logan, J.; Jayne, M.; Ma, Y.; Pradhan, K.; Wong, C.T.; Swanson, J.M.

    2010-01-01

    Loss of control over drug taking is considered a hallmark of addiction and is critical in relapse. Dysfunction of frontal brain regions involved with inhibitory control may underlie this behavior. We evaluated whether addicted subjects when instructed to purposefully control their craving responses to drug-conditioned stimuli can inhibit limbic brain regions implicated in drug craving. We used PET and 2-deoxy-2[18F]fluoro-D-glucose to measure brain glucose metabolism (marker of brain function) in 24 cocaine abusers who watched a cocaine-cue video and compared brain activation with and without instructions to cognitively inhibit craving. A third scan was obtained at baseline (without video). Statistical parametric mapping was used for analysis and corroborated with regions of interest. The cocaine-cue video increased craving during the no-inhibition condition (pre 3 {+-} 3, post 6 {+-} 3; p < 0.001) but not when subjects were instructed to inhibit craving (pre 3 {+-} 2, post 3 {+-} 3). Comparisons with baseline showed visual activation for both cocaine-cue conditions and limbic inhibition (accumbens, orbitofrontal, insula, cingulate) when subjects purposefully inhibited craving (p < 0.001). Comparison between cocaine-cue conditions showed lower metabolism with cognitive inhibition in right orbitofrontal cortex and right accumbens (p < 0.005), which was associated with right inferior frontal activation (r = -0.62, p < 0.005). Decreases in metabolism in brain regions that process the predictive (nucleus accumbens) and motivational value (orbitofrontal cortex) of drug-conditioned stimuli were elicited by instruction to inhibit cue-induced craving. This suggests that cocaine abusers may retain some ability to inhibit craving and that strengthening fronto-accumbal regulation may be therapeutically beneficial in addiction.

  3. Stimulus-dependent adjustment of reward prediction error in the midbrain.

    Directory of Open Access Journals (Sweden)

    Hiromasa Takemura

    Full Text Available Previous reports have described that neural activities in midbrain dopamine areas are sensitive to unexpected reward delivery and omission. These activities are correlated with reward prediction error in reinforcement learning models, the difference between predicted reward values and the obtained reward outcome. These findings suggest that the reward prediction error signal in the brain updates reward prediction through stimulus-reward experiences. It remains unknown, however, how sensory processing of reward-predicting stimuli contributes to the computation of reward prediction error. To elucidate this issue, we examined the relation between stimulus discriminability of the reward-predicting stimuli and the reward prediction error signal in the brain using functional magnetic resonance imaging (fMRI. Before main experiments, subjects learned an association between the orientation of a perceptually salient (high-contrast Gabor patch and a juice reward. The subjects were then presented with lower-contrast Gabor patch stimuli to predict a reward. We calculated the correlation between fMRI signals and reward prediction error in two reinforcement learning models: a model including the modulation of reward prediction by stimulus discriminability and a model excluding this modulation. Results showed that fMRI signals in the midbrain are more highly correlated with reward prediction error in the model that includes stimulus discriminability than in the model that excludes stimulus discriminability. No regions showed higher correlation with the model that excludes stimulus discriminability. Moreover, results show that the difference in correlation between the two models was significant from the first session of the experiment, suggesting that the reward computation in the midbrain was modulated based on stimulus discriminability before learning a new contingency between perceptually ambiguous stimuli and a reward. These results suggest that the human

  4. Brain reward-system activation in response to anticipation and consumption of palatable food is altered by glucagon-like peptide-1 receptor activation in humans

    NARCIS (Netherlands)

    van Bloemendaal, L.; Veltman, D. J.; ten Kulve, J. S.; Groot, P. F. C.; Ruhe, H. G.; Barkhof, F.; Sloan, J. H.; Diamant, M.; Ijzerman, R. G.

    2015-01-01

    AimTo test the hypothesis that food intake reduction after glucagon-like peptide-1 (GLP-1) receptor activation is mediated through brain areas regulating anticipatory and consummatory food reward. MethodsAs part of a larger study, we determined the effects of GLP-1 receptor activation on brain respo

  5. Floral reward presentation favored the expression of male function in the pollen-only flower Melastoma malabathricum

    Institute of Scientific and Technical Information of China (English)

    Zhong-Lai LUO; Shi CHEN; Dian-Xiang ZHANG

    2012-01-01

    Animal-pollinated plant species modulate the presentation of pollinator rewards to maximize reproductive success.In plants providing pollen as the only reward for pollinators,it is usually difficult to unravel the dual roles of reward presentation and the realization of male and female functions (pollen removal and deposition).Exploiting the two types of anther in the androecia of Melastoma malabathricum L.,we examined whether the removal of pollen for reward is regulated primarily to favor male function or female function.Pollen removal by carpenter bees from the feeding and pollination anthers,as well as pollen deposition on the stigmas,were quantified during anthesis of M.malabathricum.There was no significant difference in pollen removal rates from the feeding and pollination anthers of M.malabathricum between the onset of anthesis and flower wilting.The stigmatic pollen loads exceeded the ovule number after three sonication bouts,and female function was satisfied earlier than male function.The results support the hypothesis that the presentation of pollination reward in this species is regulated primarily to favor the expression of male function,rather than female function,in agreement with the pollen-donation hypothesis.A cooperative relationship between the feeding and pollination anthers was demonstrated in heterantherous flowers,which optimizes the balance in investments between pollinator rewards and "functional pollen" for gene transfer.

  6. Reward expectation regulates brain responses to task-relevant and task-irrelevant emotional words: ERP evidence.

    Science.gov (United States)

    Wei, Ping; Wang, Di; Ji, Liyan

    2016-02-01

    We investigated the effect of reward expectation on the processing of emotional words in two experiments using event-related potentials (ERPs). A cue indicating the reward condition of each trial (incentive vs non-incentive) was followed by the presentation of a negative or neutral word, the target. Participants were asked to discriminate the emotional content of the target word in Experiment 1 and to discriminate the color of the target word in Experiment 2, rendering the emotionality of the target word task-relevant in Experiment 1, but task-irrelevant in Experiment 2. The negative bias effect, in terms of the amplitude difference between ERPs for negative and neutral targets, was modulated by the task-set. In Experiment 1, P31 and early posterior negativity revealed a larger negative bias effect in the incentive condition than that in the non-incentive condition. However, in Experiment 2, P31 revealed a diminished negative bias effect in the incentive condition compared with that in the non-incentive condition. These results indicate that reward expectation improves top-down attentional concentration to task-relevant information, with enhanced sensitivity to the emotional content of target words when emotionality is task-relevant, but with reduced differential brain responses to emotional words when their content is task-irrelevant.

  7. Dopamine agonist increases risk taking but blunts reward-related brain activity.

    Directory of Open Access Journals (Sweden)

    Jordi Riba

    Full Text Available The use of D2/D3 dopaminergic agonists in Parkinson's disease (PD may lead to pathological gambling. In a placebo-controlled double-blind study in healthy volunteers, we observed riskier choices in a lottery task after administration of the D3 receptor-preferring agonist pramipexole thus mimicking risk-taking behavior in PD. Moreover, we demonstrate decreased activation in the rostral basal ganglia and midbrain, key structures of the reward system, following unexpected high gains and therefore propose that pathological gambling in PD results from the need to seek higher rewards to overcome the blunted response in this system.

  8. Omission of expected reward sensitizes the brain dopaminergic system of classically conditioned Atlantic salmon

    DEFF Research Database (Denmark)

    Vindas, M.A.; Höglund, Erik; Folkedal, O.

    in fishes. Here we show that the omission of expected reward (OER) leads to increased aggression towards conspecifics in classically conditioned Atlantic salmon (Salmo salar). Furthermore, in response to an acute stressor, OER fish displayed increased dopaminergic (DA) neurotransmission compared to controls....... There was also a general downregulation of dopamine receptor D1 gene expression in the telencephalon of OER groups, which suggests a coping mechanism in response to unbalanced DA metabolism. These results indicate that animals subjected to unpredictable reward conditions develop a senzitation of the DA...

  9. Endocannabinoid Signaling in Motivation, Reward, and Addiction: Influences on Mesocorticolimbic Dopamine Function.

    Science.gov (United States)

    Sagheddu, Claudia; Muntoni, Anna Lisa; Pistis, Marco; Melis, Miriam

    2015-01-01

    Evidence suggests that the endocannabinoid system has been conserved in the animal kingdom for 500 million years, and this system influences many critical behavioral processes including associative learning, reward signaling, goal-directed behavior, motor skill learning, and action-habit transformation. Additionally, the neurotransmitter dopamine has long been recognized to play a critical role in the processing of natural rewards, as well as of motivation that regulates approach and avoidance behavior. This motivational role of dopamine neurons is also based upon the evidence provided by several studies investigating disorders of dopamine pathways such as drug addiction and Parkinson's disease. From an evolutionary point of view, individuals engage in behaviors aimed at maximizing and minimizing positive and aversive consequences, respectively. Accordingly, those with the greatest fitness have a better potential to survival. Hence, deviations from fitness can be viewed as a part of the evolutionary process by means of natural selection. Given the long evolutionary history of both the endocannabinoid and dopaminergic systems, it is plausible that they must serve as fundamental and basic modulators of physiological functions and needs. Notably, endocannabinoids regulate dopamine neuronal activity and its influence on behavioral output. The goal of this chapter is to examine the endocannabinoid influence on dopamine signaling specifically related to (i) those behavioral processes that allow us to successfully adapt to ever-changing environments (i.e., reward signaling and motivational processes) and (ii) derangements from behavioral flexibility that underpin drug addiction.

  10. Neural basis of reward anticipation and its genetic determinants.

    Science.gov (United States)

    Jia, Tianye; Macare, Christine; Desrivières, Sylvane; Gonzalez, Dante A; Tao, Chenyang; Ji, Xiaoxi; Ruggeri, Barbara; Nees, Frauke; Banaschewski, Tobias; Barker, Gareth J; Bokde, Arun L W; Bromberg, Uli; Büchel, Christian; Conrod, Patricia J; Dove, Rachel; Frouin, Vincent; Gallinat, Jürgen; Garavan, Hugh; Gowland, Penny A; Heinz, Andreas; Ittermann, Bernd; Lathrop, Mark; Lemaitre, Hervé; Martinot, Jean-Luc; Paus, Tomáš; Pausova, Zdenka; Poline, Jean-Baptiste; Rietschel, Marcella; Robbins, Trevor; Smolka, Michael N; Müller, Christian P; Feng, Jianfeng; Rothenfluh, Adrian; Flor, Herta; Schumann, Gunter

    2016-04-05

    Dysfunctional reward processing is implicated in various mental disorders, including attention deficit hyperactivity disorder (ADHD) and addictions. Such impairments might involve different components of the reward process, including brain activity during reward anticipation. We examined brain nodes engaged by reward anticipation in 1,544 adolescents and identified a network containing a core striatal node and cortical nodes facilitating outcome prediction and response preparation. Distinct nodes and functional connections were preferentially associated with either adolescent hyperactivity or alcohol consumption, thus conveying specificity of reward processing to clinically relevant behavior. We observed associations between the striatal node, hyperactivity, and the vacuolar protein sorting-associated protein 4A (VPS4A) gene in humans, and the causal role of Vps4 for hyperactivity was validated in Drosophila Our data provide a neurobehavioral model explaining the heterogeneity of reward-related behaviors and generate a hypothesis accounting for their enduring nature.

  11. Video Game Training and the Reward System

    Directory of Open Access Journals (Sweden)

    Robert C. Lorenz

    2015-02-01

    Full Text Available Video games contain elaborate reinforcement and reward schedules that have the potential to maximize motivation. Neuroimaging studies suggest that video games might have an influence on the reward system. However, it is not clear whether reward-related properties represent a precondition, which biases an individual towards playing video games, or if these changes are the result of playing video games. Therefore, we conducted a longitudinal study to explore reward-related functional predictors in relation to video gaming experience as well as functional changes in the brain in response to video game training.Fifty healthy participants were randomly assigned to a video game training (TG or control group (CG. Before and after training/control period, functional magnetic resonance imaging (fMRI was conducted using a non-video game related reward task.At pretest, both groups showed strongest activation in ventral striatum (VS during reward anticipation. At posttest, the TG showed very similar VS activity compared to pretest. In the CG, the VS activity was significantly attenuated.This longitudinal study revealed that video game training may preserve reward responsiveness in the ventral striatum in a retest situation over time. We suggest that video games are able to keep striatal responses to reward flexible, a mechanism which might be of critical value for applications such as therapeutic cognitive training.

  12. Video game training and the reward system.

    Science.gov (United States)

    Lorenz, Robert C; Gleich, Tobias; Gallinat, Jürgen; Kühn, Simone

    2015-01-01

    Video games contain elaborate reinforcement and reward schedules that have the potential to maximize motivation. Neuroimaging studies suggest that video games might have an influence on the reward system. However, it is not clear whether reward-related properties represent a precondition, which biases an individual toward playing video games, or if these changes are the result of playing video games. Therefore, we conducted a longitudinal study to explore reward-related functional predictors in relation to video gaming experience as well as functional changes in the brain in response to video game training. Fifty healthy participants were randomly assigned to a video game training (TG) or control group (CG). Before and after training/control period, functional magnetic resonance imaging (fMRI) was conducted using a non-video game related reward task. At pretest, both groups showed strongest activation in ventral striatum (VS) during reward anticipation. At posttest, the TG showed very similar VS activity compared to pretest. In the CG, the VS activity was significantly attenuated. This longitudinal study revealed that video game training may preserve reward responsiveness in the VS in a retest situation over time. We suggest that video games are able to keep striatal responses to reward flexible, a mechanism which might be of critical value for applications such as therapeutic cognitive training.

  13. An obesity-associated risk allele within the FTO gene affects human brain activity for areas important for emotion, impulse control and reward in response to food images.

    Science.gov (United States)

    Wiemerslage, Lyle; Nilsson, Emil K; Solstrand Dahlberg, Linda; Ence-Eriksson, Fia; Castillo, Sandra; Larsen, Anna L; Bylund, Simon B A; Hogenkamp, Pleunie S; Olivo, Gaia; Bandstein, Marcus; Titova, Olga E; Larsson, Elna-Marie; Benedict, Christian; Brooks, Samantha J; Schiöth, Helgi B

    2016-05-01

    Understanding how genetics influences obesity, brain activity and eating behaviour will add important insight for developing strategies for weight-loss treatment, as obesity may stem from different causes and as individual feeding behaviour may depend on genetic differences. To this end, we examined how an obesity risk allele for the FTO gene affects brain activity in response to food images of different caloric content via functional magnetic resonance imaging (fMRI). Thirty participants homozygous for the rs9939609 single nucleotide polymorphism were shown images of low- or high-calorie food while brain activity was measured via fMRI. In a whole-brain analysis, we found that people with the FTO risk allele genotype (AA) had increased activity compared with the non-risk (TT) genotype in the posterior cingulate, cuneus, precuneus and putamen. Moreover, higher body mass index in the AA genotype was associated with reduced activity to food images in areas important for emotion (cingulate cortex), but also in areas important for impulse control (frontal gyri and lentiform nucleus). Lastly, we corroborate our findings with behavioural scales for the behavioural inhibition and activation systems. Our results suggest that the two genotypes are associated with differential neural processing of food images, which may influence weight status through diminished impulse control and reward processing.

  14. Linking variability in brain chemistry and circuit function through multimodal human neuroimaging

    DEFF Research Database (Denmark)

    Fisher, Patrick M; Hariri, A R

    2012-01-01

    to assay in vivo regional brain chemistry and function, respectively. Typically, these neuroimaging modalities are implemented independently despite the capacity for integrated data sets to offer unique insight into molecular mechanisms associated with brain function. Through examples from the serotonin...... and dopamine system and its effects on threat- and reward-related brain function, we review evidence for how such a multimodal neuroimaging strategy can be successfully implemented. Furthermore, we discuss how multimodal PET-fMRI can be integrated with techniques such as imaging genetics, pharmacological...

  15. Thermodynamic laws apply to brain function.

    Science.gov (United States)

    Salerian, Alen J

    2010-02-01

    Thermodynamic laws and complex system dynamics govern brain function. Thus, any change in brain homeostasis by an alteration in brain temperature, neurotransmission or content may cause region-specific brain dysfunction. This is the premise for the Salerian Theory of Brain built upon a new paradigm for neuropsychiatric disorders: the governing influence of neuroanatomy, neurophysiology, thermodynamic laws. The principles of region-specific brain function thermodynamics are reviewed. The clinical and supporting evidence including the paradoxical effects of various agents that alter brain homeostasis is demonstrated.

  16. Eloquent Brain, Ethical Challenges: Functional Brain Mapping in Neurosurgery.

    Science.gov (United States)

    Klein, Eran

    2015-06-01

    Functional brain mapping is an increasingly relied upon tool in presurgical planning and intraoperative decision making. Mapping allows personalization of structure-function relationships when surgical or other treatment of pathology puts eloquent functioning like language or vision at risk. As an innovative technology, functional brain mapping holds great promise but also raises important ethical questions. In this article, recent work in neuroethics on functional imaging and functional neurosurgery is explored and applied to functional brain mapping. Specific topics discussed in this article are incidental findings, responsible innovation, and informed consent.

  17. Functional brain imaging across development.

    Science.gov (United States)

    Rubia, Katya

    2013-12-01

    The developmental cognitive neuroscience literature has grown exponentially over the last decade. This paper reviews the functional magnetic resonance imaging (fMRI) literature on brain function development of typically late developing functions of cognitive and motivation control, timing and attention as well as of resting state neural networks. Evidence shows that between childhood and adulthood, concomitant with cognitive maturation, there is progressively increased functional activation in task-relevant lateral and medial frontal, striatal and parieto-temporal brain regions that mediate these higher level control functions. This is accompanied by progressively stronger functional inter-regional connectivity within task-relevant fronto-striatal and fronto-parieto-temporal networks. Negative age associations are observed in earlier developing posterior and limbic regions, suggesting a shift with age from the recruitment of "bottom-up" processing regions towards "top-down" fronto-cortical and fronto-subcortical connections, leading to a more mature, supervised cognition. The resting state fMRI literature further complements this evidence by showing progressively stronger deactivation with age in anti-correlated task-negative resting state networks, which is associated with better task performance. Furthermore, connectivity analyses during the resting state show that with development increasingly stronger long-range connections are being formed, for example, between fronto-parietal and fronto-cerebellar connections, in both task-positive networks and in task-negative default mode networks, together with progressively lesser short-range connections, suggesting progressive functional integration and segregation with age. Overall, evidence suggests that throughout development between childhood and adulthood, there is progressive refinement and integration of both task-positive fronto-cortical and fronto-subcortical activation and task-negative deactivation, leading to

  18. Employee reward

    OpenAIRE

    2014-01-01

    Objectives: • To present the main historical and theoretical foundations underpinning contemporary employee reward practice. • To define employee reward and identify the key components of reward. • To explore the concept of reward management and the benefits and difficulties associated with introducing a strategic approach to reward. • To consider key employee reward choices facing organisations in the contemporary era. • To explore the economic and legal context for reward and the implicatio...

  19. Functional brain imaging; Funktionelle Hirnbildgebung

    Energy Technology Data Exchange (ETDEWEB)

    Gizewski, E.R. [Medizinische Universitaet Innsbruck, Universitaetsklinik fuer Neuroradiologie, Innsbruck (Austria)

    2016-02-15

    Functional magnetic resonance imaging (fMRI) is a non-invasive method that has become one of the major tools for understanding human brain function and in recent years has also been developed for clinical applications. Changes in hemodynamic signals correspond to changes in neuronal activity with good spatial and temporal resolution in fMRI. Using high-field MR systems and increasingly dedicated statistics and postprocessing, activated brain areas can be detected and superimposed on anatomical images. Currently, fMRI data are often combined in multimodal imaging, e. g. with diffusion tensor imaging (DTI) sequences. This method is helping to further understand the physiology of cognitive brain processes and is also being used in a number of clinical applications. In addition to the blood oxygenation level-dependent (BOLD) signals, this article deals with the construction of fMRI investigations, selection of paradigms and evaluation in the clinical routine. Clinically, this method is mainly used in the planning of brain surgery, analyzing the location of brain tumors in relation to eloquent brain areas and the lateralization of language processing. As the BOLD signal is dependent on the strength of the magnetic field as well as other limitations, an overview of recent developments is given. Increases of magnetic field strength (7 T), available head coils and advances in MRI analytical methods have led to constant improvement in fMRI signals and experimental design. Especially the depiction of eloquent brain regions can be done easily and quickly and has become an essential part of presurgical planning. (orig.) [German] Mittlerweile ist die funktionelle MRT (fMRT) eine Methode, die nicht mehr nur in der neurowissenschaftlichen Routine verwendet wird. Die fMRT ermoeglicht die nichtinvasive Darstellung der Hirnaktivitaet in guter raeumlicher und zeitlicher Aufloesung unter Ausnutzung der Durchblutungsaenderung aufgrund der erhoehten Nervenzellaktivitaet. Unter

  20. Resting state brain activity and functional brain mapping

    Institute of Scientific and Technical Information of China (English)

    Zhao Xiaohu; Wang Peijun; Tang Xiaowei

    2007-01-01

    Functional brain imaging studies commonly use either resting or passive task states as their control conditions, and typically identify the activation brain region associated with a specific task by subtracting the resting from the active task conditions. Numerous studies now suggest, however, that the resting state may not reflect true mental "rest" conditions. The mental activity that occurs during"rest" might therefore greatly influence the functional neuroimaging observations that are collected through the usual subtracting analysis strategies. Exploring the ongoing mental processes that occur during resting conditions is thus of particular importance for deciphering functional brain mapping results and obtaining a more comprehensive understanding of human brain functions. In this review article, we will mainly focus on the discussion of the current research background of functional brain mapping at resting state and the physiological significance of the available neuroimaging data.

  1. Functional Prions in the Brain.

    Science.gov (United States)

    Rayman, Joseph B; Kandel, Eric R

    2017-01-03

    Prions are proteins that can adopt self-perpetuating conformations and are traditionally regarded as etiological agents of infectious neurodegenerative diseases in humans, such as Creutzfeldt-Jakob disease, kuru, and transmissible encephalopathies. More recently, a growing consensus has emerged that prion-like, self-templating mechanisms also underlie a variety of neurodegenerative disorders, including amyotrophic lateral sclerosis, Alzheimer's disease, and Huntington's disease. Perhaps most surprising, not all prion-like aggregates are associated with pathological changes. There are now several examples of prion-like proteins in mammals that serve positive biological functions in their aggregated state. In this review, we discuss functional prions in the nervous system, with particular emphasis on the cytoplasmic polyadenylation element-binding protein (CPEB) and the role of its prion-like aggregates in synaptic plasticity and memory. We also mention a more recent example of a functional prion-like protein in the brain, TIA-1, and its role during stress. These studies of functional prion-like proteins have provided a number of generalizable insights on how prion-based protein switches may operate to serve physiological functions in higher eukaryotes.

  2. Aging and functional brain networks

    Energy Technology Data Exchange (ETDEWEB)

    Tomasi D.; Tomasi, D.; Volkow, N.D.

    2011-07-11

    Aging is associated with changes in human brain anatomy and function and cognitive decline. Recent studies suggest the aging decline of major functional connectivity hubs in the 'default-mode' network (DMN). Aging effects on other networks, however, are largely unknown. We hypothesized that aging would be associated with a decline of short- and long-range functional connectivity density (FCD) hubs in the DMN. To test this hypothesis, we evaluated resting-state data sets corresponding to 913 healthy subjects from a public magnetic resonance imaging database using functional connectivity density mapping (FCDM), a voxelwise and data-driven approach, together with parallel computing. Aging was associated with pronounced long-range FCD decreases in DMN and dorsal attention network (DAN) and with increases in somatosensory and subcortical networks. Aging effects in these networks were stronger for long-range than for short-range FCD and were also detected at the level of the main functional hubs. Females had higher short- and long-range FCD in DMN and lower FCD in the somatosensory network than males, but the gender by age interaction effects were not significant for any of the networks or hubs. These findings suggest that long-range connections may be more vulnerable to aging effects than short-range connections and that, in addition to the DMN, the DAN is also sensitive to aging effects, which could underlie the deterioration of attention processes that occurs with aging.

  3. Cocaine enhances resistance to extinction of responding for brain-stimulation reward in adult prenatally stressed rats.

    Science.gov (United States)

    Gao, Shuibo; Suenaga, Toshiko; Oki, Yutaka; Yukie, Masao; Nakahara, Daiichiro

    2011-10-01

    The present experiment assessed whether prenatal stress (PS) can alter the ability of acute and chronic cocaine administration to increase and decrease the rewarding effectiveness of the medial forebrain bundle (MFB) using intracranial self-stimulation (ICSS), and also whether PS can affect the extinction of the MFB stimulation response. Adult male offspring of female rats that received PS or no PS (nPS) were implanted with MFB stimulating electrodes, and were then tested in ICSS paradigms. In both nPS and PS offspring, acute cocaine injection decreased ICSS thresholds dose-dependently. However, the threshold-lowering effects at any dose were not significantly different between groups. There was also no group-difference in the threshold-elevating effects of chronic cocaine administration. Nevertheless, chronically drug-administered PS rats exhibited a resistance to the extinguishing of the response for brain-stimulation reward when acutely treated with cocaine, as compared to extinction without cocaine treatment. The results suggest that PS may weaken the ability for response inhibition under cocaine loading in male adult offspring.

  4. Toward discovery science of human brain function

    DEFF Research Database (Denmark)

    Biswal, Bharat B; Mennes, Maarten; Zuo, Xi-Nian

    2010-01-01

    Although it is being successfully implemented for exploration of the genome, discovery science has eluded the functional neuroimaging community. The core challenge remains the development of common paradigms for interrogating the myriad functional systems in the brain without the constraints...... in the brain. To initiate discovery science of brain function, the 1000 Functional Connectomes Project dataset is freely accessible at www.nitrc.org/projects/fcon_1000/....

  5. Personality is reflected in the brain's intrinsic functional architecture.

    Directory of Open Access Journals (Sweden)

    Jonathan S Adelstein

    Full Text Available Personality describes persistent human behavioral responses to broad classes of environmental stimuli. Investigating how personality traits are reflected in the brain's functional architecture is challenging, in part due to the difficulty of designing appropriate task probes. Resting-state functional connectivity (RSFC can detect intrinsic activation patterns without relying on any specific task. Here we use RSFC to investigate the neural correlates of the five-factor personality domains. Based on seed regions placed within two cognitive and affective 'hubs' in the brain--the anterior cingulate and precuneus--each domain of personality predicted RSFC with a unique pattern of brain regions. These patterns corresponded with functional subdivisions responsible for cognitive and affective processing such as motivation, empathy and future-oriented thinking. Neuroticism and Extraversion, the two most widely studied of the five constructs, predicted connectivity between seed regions and the dorsomedial prefrontal cortex and lateral paralimbic regions, respectively. These areas are associated with emotional regulation, self-evaluation and reward, consistent with the trait qualities. Personality traits were mostly associated with functional connections that were inconsistently present across participants. This suggests that although a fundamental, core functional architecture is preserved across individuals, variable connections outside of that core encompass the inter-individual differences in personality that motivate diverse responses.

  6. Behavioral and Brain Functions. A new journal

    Directory of Open Access Journals (Sweden)

    Sagvolden Terje

    2005-04-01

    Full Text Available Abstract Behavioral and Brain Functions (BBF is an Open Access, peer-reviewed, online journal considering original research, review, and modeling articles in all aspects of neurobiology or behavior, favoring research that relates to both domains. Behavioral and Brain Functions is published by BioMed Central. The greatest challenge for empirical science is to understand human behavior; how human behavior arises from the myriad functions such as attention, language, memory and emotion; how these functions are reflected in brain structures and functions; and how the brain and behavior are altered in disease. Behavioral and Brain Functions covers the entire area of behavioral and cognitive neuroscience – an area where animal studies traditionally play a prominent role. Behavioral and Brain Functions is published online, allowing unlimited space for figures, extensive datasets to allow readers to study the data for themselves, and moving pictures, which are important qualities assisting communication in modern science.

  7. Cocaine- and amphetamine-regulated transcript (CART) peptide immunoreactivity in feeding- and reward-related brain areas of young OLETF rats.

    NARCIS (Netherlands)

    Armbruszt, S.; Abraham, H.; Figler, M.; Kozicz, T.L.; Hajnal, A.

    2013-01-01

    Cocaine- and amphetamine-regulated transcript (CART) peptide is expressed in brain areas involved in the control of appetite, drug reward and homeostatic regulation and it has an overall anorexigenic effect. Recently, we have shown that CART peptide immunoreactivity was significantly reduced in the

  8. Spatiotemporal dissociation of brain activity underlying threat and reward in social anxiety disorder.

    Science.gov (United States)

    A Richey, John; Ghane, Merage; Valdespino, Andrew; Coffman, Marika C; Strege, Marlene V; White, Susan W; Ollendick, Thomas H

    2016-10-19

    Social anxiety disorder (SAD) involves abnormalities in social motivation, which may be independent of well-documented differences in fear and arousal systems. Yet, the neurobiology underlying motivational difficulties in SAD is not well understood. The aim of the current study was to spatiotemporally dissociate reward circuitry dysfunction from alterations in fear and arousal-related neural activity during anticipation and notification of social and non-social reward and punishment. During fMRI acquisition, non-depressed adults with social anxiety disorder (SAD; N = 21) and age-, sex- and IQ-matched control subjects (N = 22) completed eight runs of an incentive delay task, alternating between social and monetary outcomes and interleaved in alternating order between gain and loss outcomes. Adults with SAD demonstrated significantly reduced neural activity in ventral striatum during the anticipation of positive but not negative social outcomes. No differences between the SAD and control groups were observed during anticipation of monetary gain or loss outcomes or during anticipation of negative social images. However, consistent with previous work, the SAD group demonstrated amygdala hyper-activity upon notification of negative social outcomes. Degraded anticipatory processing in bilateral ventral striatum in SAD was constrained exclusively to anticipation of positive social information and dissociable from the effects of negative social outcomes previously observed in the amygdala. Alterations in anticipation-related neural signals may represent a promising target for treatment that is not addressed by available evidence-based interventions, which focus primarily on fear extinction and habituation processes.

  9. Dietary fat induces sustained reward response in the human brain without primary taste cortex discrimination

    Directory of Open Access Journals (Sweden)

    Hélène eTzieropoulos

    2013-02-01

    Full Text Available To disentangle taste from reward responses in the human gustatory cortex, we combined high density electro-encephalography with a gustometer delivering tastant puffs to the tip of the tongue. Stimuli were pure tastants (salt solutions at two concentrations, caloric emulsions of identical taste (two milk preparations differing in fat content and a mixture of high fat milk with the lowest salt concentration. Early event-related potentials showed a dose-response effect for increased taste intensity, with higher amplitude and shorter latency for high compared to low salt concentration, but not for increased fat content. However, the amplitude and distribution of late potentials were modulated by fat content independently of reported intensity and discrimination. Neural source estimation revealed a sustained activation of reward areas to the two high-fat stimuli. The results suggest calorie detection through specific sensors on the tongue independent of perceived taste. Finally, amplitude variation of the first peak in the event-related potential to the different stimuli correlated with papilla density, suggesting a higher discrimination power for subjects with more fungiform papillae.

  10. Novelty increases the mesolimbic functional connectivity of the substantia nigra/ventral tegmental area (SN/VTA) during reward anticipation: Evidence from high-resolution fMRI.

    Science.gov (United States)

    Krebs, R M; Heipertz, D; Schuetze, H; Duzel, E

    2011-09-15

    Reward and novelty are potent learning signals that critically rely on dopaminergic midbrain responses. Recent findings suggest that although reward and novelty are likely to interact, both functions may be subserved by distinct neuronal clusters. We used high-resolution functional magnetic resonance imaging (fMRI) to isolate neural responses to reward and novelty within the human substantia nigra/ventral tegmental area (SN/VTA) complex to investigate the spatial delineation and integration of reward- and novelty-related activity clusters. We demonstrate that distinct clusters within the caudal portion of the medial SN/VTA and the lateral portion of the right SN are predominantly modulated by the anticipation of reward, while a more rostral part of the medial SN/VTA was exclusively modulated by novelty. In addition, the caudal medial SN/VTA cluster embodied an interaction between novelty and reward where novelty selectively increased reward-anticipation responses. This interaction, in turn, was paralleled by differences in the functional-connectivity patterns of these SN/VTA regions. Specifically, novel as compared to familiar reward-predictive stimuli increased the functional connectivity of the medial SN/VTA with mesolimbic regions, including the nucleus accumbens and the hippocampus, as well as with the primary visual cortex. This functional correlation may highlight how afferents of the medial SN/VTA provide integrative information about novelty and reward, or, alternatively, how medial SN/VTA activity may modulate memory processes for novel events associated with rewards.

  11. Reward and decision processes in the brains of humans and nonhuman primates.

    Science.gov (United States)

    Sirigu, Angela; Duhamel, Jean-René

    2016-03-01

    Choice behavior requires weighing multiple decision variables, such as utility, uncertainty, delay, or effort, that combine to define a subjective value for each considered option or course of action. This capacity is based on prior learning about potential rewards (and punishments) that result from prior actions. When made in a social context, decisions can involve strategic thinking about the intentions of others and about the impact of others' behavior on one's own outcome. Valuation is also influenced by different emotions that serve to adaptively regulate our choices in order to, for example, stay away from excessively risky gambles, prevent future regrets, or avoid personal rejection or conflicts. Drawing on economic theory and on advances in the study of neuronal mechanisms, we review relevant recent experiments in nonhuman primates and clinical observations made in neurologically impaired patients suffering from impaired decision-making capacities.

  12. Optogenetics in Freely Moving Mammals: Dopamine and Reward.

    Science.gov (United States)

    Zhang, Feng; Tsai, Hsing-Chen; Airan, Raag D; Stuber, Garret D; Adamantidis, Antoine R; de Lecea, Luis; Bonci, Antonello; Deisseroth, Karl

    2015-08-03

    Brain reward systems play a central role in the cognitive and hedonic behaviors of mammals. Multiple neuron types and brain regions are involved in reward processing, posing fascinating scientific questions, and major experimental challenges. Using diverse approaches including genetics, electrophysiology, imaging, and behavioral analysis, a large body of research has focused on both normal functioning of the reward circuitry and on its potential significance in neuropsychiatric diseases. In this introduction, we illustrate a real-world application of optogenetics to mammalian behavior and physiology, delineating procedures and technologies for optogenetic control of individual components of the reward circuitry. We describe the experimental setup and protocol for integrating optogenetic modulation of dopamine neurons with fast-scan cyclic voltammetry, conditioned place preference, and operant conditioning to assess the causal role of well-defined electrical and biochemical signals in reward-related behavior.

  13. Addiction: Beyond dopamine reward circuitry

    Energy Technology Data Exchange (ETDEWEB)

    Volkow, N.D.; Wang, G.; Volkow, N.D.; Wang, G.-J.; Fowler, J.S.; Tomasi, D.; Telang, F.

    2011-09-13

    Dopamine (DA) is considered crucial for the rewarding effects of drugs of abuse, but its role in addiction is much less clear. This review focuses on studies that used PET to characterize the brain DA system in addicted subjects. These studies have corroborated in humans the relevance of drug-induced fast DA increases in striatum [including nucleus accumbens (NAc)] in their rewarding effects but have unexpectedly shown that in addicted subjects, drug-induced DA increases (as well as their subjective reinforcing effects) are markedly blunted compared with controls. In contrast, addicted subjects show significant DA increases in striatum in response to drug-conditioned cues that are associated with self-reports of drug craving and appear to be of a greater magnitude than the DA responses to the drug. We postulate that the discrepancy between the expectation for the drug effects (conditioned responses) and the blunted pharmacological effects maintains drug taking in an attempt to achieve the expected reward. Also, whether tested during early or protracted withdrawal, addicted subjects show lower levels of D2 receptors in striatum (including NAc), which are associated with decreases in baseline activity in frontal brain regions implicated in salience attribution (orbitofrontal cortex) and inhibitory control (anterior cingulate gyrus), whose disruption results in compulsivity and impulsivity. These results point to an imbalance between dopaminergic circuits that underlie reward and conditioning and those that underlie executive function (emotional control and decision making), which we postulate contributes to the compulsive drug use and loss of control in addiction.

  14. Validation and extension of the reward-mountain model

    Directory of Open Access Journals (Sweden)

    Yannick-André eBreton

    2013-10-01

    Full Text Available The reward-mountain model relates the vigor of reward seeking to the strength and cost of reward. Application of this model provides information about the stage of processing at which manipulations such as drug administration, lesions, deprivation states, and optogenetic interventions act to alter reward seeking. The model has been updated by incorporation of new information about frequency following in the directly stimulated neurons responsible for brain stimulation reward and about the function that maps objective opportunity costs into subjective ones. The behavioral methods for applying the model have been updated and improved as well. To assess the impact of these changes, two related predictions of the model that were supported by earlier work have been retested: 1 altering the duration of rewarding brain stimulation should change the pulse frequency required to produce a reward of half-maximal intensity, and 2 this manipulation should not change the opportunity cost at which half-maximal performance is directed at earning a maximally intense reward. Prediction 1 was supported in all six subjects, but prediction 2 was supported in only three. The latter finding is interpreted to reflect recruitment, at some stimulation sites, of a heterogeneous reward substrate comprising dual, parallel circuits that integrate the stimulation-induced neural signals.

  15. The hypocretins and the reward function: what have we learned so far?

    Directory of Open Access Journals (Sweden)

    Benjamin eBoutrel

    2013-06-01

    Full Text Available A general consensus acknowledges that drug consumption (including alcohol, tobacco and illicit drugs constitutes the leading cause of preventable death worldwide. Dramatically, drug abuse is not only a major cause of mortality. The comorbid long-term debilitating effects also significantly deteriorates the quality of life of individuals suffering from addiction disorders. Despite the large body of evidence delineating the cellular and molecular adaptations induced by chronic drug consumption, the brain mechanisms responsible for drug craving and relapse remain insufficiently understood, and even the most recent developments in the field have not brought significant improvement in the management of drug dependence. Though, recent preclinical evidence suggests that disrupting the hypocretin (orexin system may serve as an anticraving medication therapy. Here, we discuss how the hypocretins, which orchestrate normal wakefulness, metabolic health and the execution of goal-oriented behaviors, may be compromised and contribute to elicit compulsive drug seeking. We propose an overview on the most recent studies demonstrating an important role for the hypocretin neuropeptide system in the regulation of drug reward and the prevention of drug relapse, and we question the relevance of disrupting the hypocretin system to alleviate symptoms of drug addiction.

  16. A reward-modulated hebbian learning rule can explain experimentally observed network reorganization in a brain control task.

    Science.gov (United States)

    Legenstein, Robert; Chase, Steven M; Schwartz, Andrew B; Maass, Wolfgang

    2010-06-23

    It has recently been shown in a brain-computer interface experiment that motor cortical neurons change their tuning properties selectively to compensate for errors induced by displaced decoding parameters. In particular, it was shown that the three-dimensional tuning curves of neurons whose decoding parameters were reassigned changed more than those of neurons whose decoding parameters had not been reassigned. In this article, we propose a simple learning rule that can reproduce this effect. Our learning rule uses Hebbian weight updates driven by a global reward signal and neuronal noise. In contrast to most previously proposed learning rules, this approach does not require extrinsic information to separate noise from signal. The learning rule is able to optimize the performance of a model system within biologically realistic periods of time under high noise levels. Furthermore, when the model parameters are matched to data recorded during the brain-computer interface learning experiments described above, the model produces learning effects strikingly similar to those found in the experiments.

  17. Imbalance in the sensitivity to different types of rewards in pathological gambling.

    Science.gov (United States)

    Sescousse, Guillaume; Barbalat, Guillaume; Domenech, Philippe; Dreher, Jean-Claude

    2013-08-01

    Pathological gambling is an addictive disorder characterized by a persistent and compulsive desire to engage in gambling activities. This maladaptive behaviour has been suggested to result from a decreased sensitivity to experienced rewards, regardless of reward type. Alternatively, pathological gambling might reflect an imbalance in the sensitivity to monetary versus non-monetary incentives. To directly test these two hypotheses, we examined how the brain reward circuit of pathological gamblers responds to different types of rewards. Using functional magnetic resonance imaging, we compared the brain responses of 18 pathological gamblers and 20 healthy control subjects while they engaged in a simple incentive task manipulating both monetary and visual erotic rewards. During reward anticipation, the ventral striatum of pathological gamblers showed a differential response to monetary versus erotic cues, essentially driven by a blunted reactivity to cues predicting erotic stimuli. This differential response correlated with the severity of gambling symptoms and was paralleled by a reduced behavioural motivation for erotic rewards. During reward outcome, a posterior orbitofrontal cortex region, responding to erotic rewards in both groups, was further recruited by monetary gains in pathological gamblers but not in control subjects. Moreover, while ventral striatal activity correlated with subjective ratings assigned to monetary and erotic rewards in control subjects, it only correlated with erotic ratings in gamblers. Our results point to a differential sensitivity to monetary versus non-monetary rewards in pathological gambling, both at the motivational and hedonic levels. Such an imbalance might create a bias towards monetary rewards, potentially promoting addictive gambling behaviour.

  18. Trisomy of the G protein-coupled K+ channel gene, Kcnj6, affects reward mechanisms, cognitive functions, and synaptic plasticity in mice.

    Science.gov (United States)

    Cooper, Ayelet; Grigoryan, Gayane; Guy-David, Liora; Tsoory, Michael M; Chen, Alon; Reuveny, Eitan

    2012-02-14

    G protein-activated inwardly rectifying K+ channels (GIRK) generate slow inhibitory postsynaptic potentials in the brain via G(i/o) protein-coupled receptors. GIRK2, a GIRK subunit, is widely abundant in the brain and has been implicated in various functions and pathologies, such as learning and memory, reward, motor coordination, and Down syndrome. Down syndrome, the most prevalent cause of mental retardation, results from the presence of an extra maternal chromosome 21 (trisomy 21), which comprises the Kcnj6 gene (GIRK2). The present study examined the behaviors and cellular physiology properties in mice harboring a single trisomy of the Kcnj6 gene. Kcnj6 triploid mice exhibit deficits in hippocampal-dependent learning and memory, altered responses to rewards, hampered depotentiation, a form of excitatory synaptic plasticity, and have accentuated long-term synaptic depression. Collectively the findings suggest that triplication of Kcnj6 gene may play an active role in some of the abnormal neurological phenotypes found in Down syndrome.

  19. Toward discovery science of human brain function.

    Science.gov (United States)

    Biswal, Bharat B; Mennes, Maarten; Zuo, Xi-Nian; Gohel, Suril; Kelly, Clare; Smith, Steve M; Beckmann, Christian F; Adelstein, Jonathan S; Buckner, Randy L; Colcombe, Stan; Dogonowski, Anne-Marie; Ernst, Monique; Fair, Damien; Hampson, Michelle; Hoptman, Matthew J; Hyde, James S; Kiviniemi, Vesa J; Kötter, Rolf; Li, Shi-Jiang; Lin, Ching-Po; Lowe, Mark J; Mackay, Clare; Madden, David J; Madsen, Kristoffer H; Margulies, Daniel S; Mayberg, Helen S; McMahon, Katie; Monk, Christopher S; Mostofsky, Stewart H; Nagel, Bonnie J; Pekar, James J; Peltier, Scott J; Petersen, Steven E; Riedl, Valentin; Rombouts, Serge A R B; Rypma, Bart; Schlaggar, Bradley L; Schmidt, Sein; Seidler, Rachael D; Siegle, Greg J; Sorg, Christian; Teng, Gao-Jun; Veijola, Juha; Villringer, Arno; Walter, Martin; Wang, Lihong; Weng, Xu-Chu; Whitfield-Gabrieli, Susan; Williamson, Peter; Windischberger, Christian; Zang, Yu-Feng; Zhang, Hong-Ying; Castellanos, F Xavier; Milham, Michael P

    2010-03-09

    Although it is being successfully implemented for exploration of the genome, discovery science has eluded the functional neuroimaging community. The core challenge remains the development of common paradigms for interrogating the myriad functional systems in the brain without the constraints of a priori hypotheses. Resting-state functional MRI (R-fMRI) constitutes a candidate approach capable of addressing this challenge. Imaging the brain during rest reveals large-amplitude spontaneous low-frequency (science of brain function, the 1000 Functional Connectomes Project dataset is freely accessible at www.nitrc.org/projects/fcon_1000/.

  20. Effort responses to suboptimal reward cues are related to striatal dopaminergic functioning

    NARCIS (Netherlands)

    Pas, P.; Custers, R.; Bijleveld, E.H.; Vink, M.

    2014-01-01

    Reward cues have been found to increase the investment of effort in tasks even when cues are presented suboptimally (i.e. very briefly), making them hard to consciously detect. Such effort responses to suboptimal reward cues are assumed to rely mainly on the mesolimbic dopamine system, including the

  1. Pain and suicidality: insights from reward and addiction neuroscience.

    Science.gov (United States)

    Elman, Igor; Borsook, David; Volkow, Nora D

    2013-10-01

    Suicidality is exceedingly prevalent in pain patients. Although the pathophysiology of this link remains unclear, it may be potentially related to the partial congruence of physical and emotional pain systems. The latter system's role in suicide is also conspicuous during setbacks and losses sustained in the context of social attachments. Here we propose a model based on the neural pathways mediating reward and anti-reward (i.e., allostatic adjustment to recurrent activation of the reward circuitry); both are relevant etiologic factors in pain, suicide and social attachments. A comprehensive literature search on neurobiology of pain and suicidality was performed. The collected articles were critically reviewed and relevant data were extracted and summarized within four key areas: (1) physical and emotional pain, (2) emotional pain and social attachments, (3) pain- and suicide-related alterations of the reward and anti-reward circuits as compared to addiction, which is the premier probe for dysfunction of these circuits and (4) mechanistically informed treatments of co-occurring pain and suicidality. Pain-, stress- and analgesic drugs-induced opponent and proponent states of the mesolimbic dopaminergic pathways may render reward and anti-reward systems vulnerable to sensitization, cross-sensitization and aberrant learning of contents and contexts associated with suicidal acts and behaviors. These findings suggest that pain patients exhibit alterations in the brain circuits mediating reward (depressed function) and anti-reward (sensitized function) that may affect their proclivity for suicide and support pain and suicidality classification among other "reward deficiency syndromes" and a new proposal for "enhanced anti-reward syndromes". We suggest that interventions aimed at restoring the balance between the reward and anti-reward networks in patients with chronic pain may help decreasing their suicide risk.

  2. Brain activity in advantageous and disadvantageous situations: implications for reward/punishment sensitivity in different situations.

    Directory of Open Access Journals (Sweden)

    Guangheng Dong

    Full Text Available OBJECTIVE: This study modeled win and lose trials in a simple gambling task to examine the effect of entire win-lose situations (WIN, LOSS, or TIE on single win/lose trials and related neural underpinnings. METHODS: The behavior responses and brain activities of 17 participants were recorded by an MRI scanner while they performed a gambling task. Different conditions were compared to determine the effect of the task on the behavior and brain activity of the participants. Correlations between brain activity and behavior were calculated to support the imaging results. RESULTS: In win trials, LOSS caused less intense posterior cingulate activity than TIE. In lose trials, LOSS caused more intense activity in the right superior temporal gyrus, bilateral superior frontal gyrus, bilateral anterior cingulate, bilateral insula cortex, and left orbitofrontal cortex than WIN and TIE. CONCLUSIONS: The experiences of the participants in win trials showed great similarity among different win-lose situations. However, the brain activity and behavior responses of the participants in lose trials indicated that they experienced stronger negative emotion in LOSS. The participants also showed an increased desire to win in LOSS than in WIN or TIE conditions.

  3. The gravitational field and brain function

    Science.gov (United States)

    Mei, Lei; Zhou, Chuan-Dai; Lan, Jing-Quan; Wang, Zhi-Ging; Wu, Wen-Can; Xue, Xin-Min

    The frontal cortex is recognized as the highest adaptive control center of the human brain. The principle of the ``frontalization'' of human brain function offers new possibilities for brain research in space. There is evolutionary and experimental evidence indicating the validity of the principle, including it's role in nervous response to gravitational stimulation. The gravitational field is considered here as one of the more constant and comprehensive factors acting on brain evolution, which has undergone some successive crucial steps: ``encephalization'', ``corticalization'', ``lateralization'' and ``frontalization''. The dominating effects of electrical responses from the frontal cortex have been discovered 1) in experiments under gravitational stimulus; and 2) in processes potentially relating to gravitational adaptation, such as memory and learning, sensory information processing, motor programing, and brain state control. A brain research experiment during space flight is suggested to test the role of the frontal cortex in space adaptation and it's potentiality in brain control.

  4. Loss in Connectivity (LoCo) among regions of the brain reward system in alcohol dependence

    OpenAIRE

    Kuceyeski, Amy; Meyerhoff, Dieter J.; Timothy C. Durazzo; Raj, Ashish

    2012-01-01

    A recently developed measure of structural brain connectivity disruption, the Loss in Connectivity (LoCo), is adapted for studies in alcohol dependence. LoCo uses independent tractography information from young healthy controls to project the location of white matter microstructure abnormalities in alcohol dependent vs. non-dependent individuals onto connected gray matter regions. The LoCo scores are computed from white matter abnormality masks derived at two levels: 1) group-wise differences...

  5. Loss in connectivity among regions of the brain reward system in alcohol dependence

    OpenAIRE

    Kuceyeski, A.; Meyerhoff, DJ; Durazzo, TC; Raj, A.

    2013-01-01

    A recently developed measure of structural brain connectivity disruption, the loss in connectivity (LoCo), is adapted for studies in alcohol dependence. LoCo uses independent tractography information from young healthy controls to project the location of white matter (WM) microstructure abnormalities in alcohol-dependent versus nondependent individuals onto connected gray matter (GM) regions. LoCo scores are computed from WM abnormality masks derived at two levels: (1) groupwise differences o...

  6. Network Assemblies in the Functional Brain

    Science.gov (United States)

    Sepulcre, Jorge; Sabuncu, Mert R.; Johnson, Keith A.

    2012-01-01

    Purpose of review This review focuses on recent advances in functional connectivity MRI and renewed interest in knowing the large-scale functional network assemblies in the brain. We also consider some methodological aspects of graph theoretical analysis. Recent findings Network science applied to neuroscience is quickly growing in recent years. The characterization of the functional connectomes in normal and pathological brain conditions is now a priority for researchers in the neuropsychiatric field and current findings have provided new insights regarding the pivotal role of network epicenters and specific configurations of the functional networks in the brain. Summary Functional connectivity and its analytical tools are providing organization of the functional brain that will be key for the understanding of pathologies in neurology. PMID:22766721

  7. On development of functional brain connectivity in the young brain

    Directory of Open Access Journals (Sweden)

    G.E. Anna-Jasmijn eHoff

    2013-10-01

    Full Text Available Our brain is a complex network of structurally and functionally interconnected regions, shaped to efficiently process and integrate information. The development from a brain equipped with basic functionalities to an efficient network facilitating complex behavior starts during gestation and continues into adulthood. Resting-state functional MRI (rs-fMRI enables the examination of developmental aspects of functional connectivity and functional brain networks. This review will discuss changes observed in the developing brain on the level of network functional connectivity (FC from a gestational age of 20 weeks onwards. We discuss findings of resting-state fMRI studies showing that functional network development starts during gestation, creating a foundation for each of the resting-state networks to be established. Visual and sensorimotor areas are reported to develop first, with other networks, at different rates, increasing both in network connectivity and size over time. Reaching childhood, marked fine-tuning and specialization takes place in the regions necessary for higher-order cognitive functions.

  8. Is avolition in schizophrenia associated with a deficit of dorsal caudate activity? A functional magnetic resonance imaging study during reward anticipation and feedback

    OpenAIRE

    Mucci, A.; D. Dima; Soricelli, A; Volpe, U.; Bucci, P.; Frangou, S.; Prinster, A.; Salvatore, M; Galderisi, S.; Maj, M.

    2015-01-01

    BACKGROUND: The neurobiological underpinnings of avolition in schizophrenia remain unclear. Most brain imaging research has focused on reward prediction deficit and on ventral striatum dysfunction, but findings are not consistent. In the light of accumulating evidence that both ventral striatum and dorsal caudate play a key role in motivation, we investigated ventral striatum and dorsal caudate activation during processing of reward or loss in patients with schizophrenia. METHOD: We used ...

  9. Decision and Reward in Intertemporal Choice: The Roles of Brain Development, Inter-individual Differences and Pharmacological Influences

    OpenAIRE

    Ripke, Stephan

    2013-01-01

    Human decision making is closely related to reward processing because many decisions rely to a certain degree on the evaluation of different outcome values. Reward-based decisions can be health-related, for example if someone has to compare the outcome value of the instant reward of smoking a cigarette to that of the long term goal of keeping well and fit. Such comparisons do not only rely on the nominal value of the alternatives but also on devaluation of rewards over time. The value of bein...

  10. No laughing matter: intranasal oxytocin administration changes functional brain connectivity during exposure to infant laughter.

    Science.gov (United States)

    Riem, Madelon M E; van IJzendoorn, Marinus H; Tops, Mattie; Boksem, Maarten A S; Rombouts, Serge A R B; Bakermans-Kranenburg, Marian J

    2012-04-01

    Infant laughter is a rewarding experience. It activates neural reward circuits and promotes parental proximity and care, thus facilitating parent-infant attachment. The neuropeptide oxytocin might enhance the incentive salience of infant laughter by modulating neural circuits related to the perception of infant cues. In a randomized controlled trial with functional magnetic resonance imaging we investigated the influence of intranasally administered oxytocin on functional brain connectivity in response to infant laughter. Blood oxygenation level-dependent responses to infant laughter were measured in 22 nulliparous women who were administered oxytocin and 20 nulliparous women who were administered a placebo. Elevated oxytocin levels reduced activation in the amygdala during infant laughter and enhanced functional connectivity between the amygdala and the orbitofrontal cortex, the anterior cingulate, the hippocampus, the precuneus, the supramarginal gyri, and the middle temporal gyrus. Increased functional connectivity between the amygdala and regions involved in emotion regulation may reduce negative emotional arousal while enhancing the incentive salience of the infant laughter.

  11. On Optimality of Greedy Policy for a Class of Standard Reward Function of Restless Multi-armed Bandit Problem

    CERN Document Server

    Liu, Quan; Chen, Lin

    2011-01-01

    In this paper,we consider the restless bandit problem, which is one of the most well-studied generalizations of the celebrated stochastic multi-armed bandit problem in decision theory. However, it is known be PSPACE-Hard to approximate to any non-trivial factor. Thus the optimality is very difficult to obtain due to its high complexity. A natural method is to obtain the greedy policy considering its stability and simplicity. However, the greedy policy will result in the optimality loss for its intrinsic myopic behavior generally. In this paper, by analyzing one class of so-called standard reward function, we establish the closed-form condition about the discounted factor \\beta such that the optimality of the greedy policy is guaranteed under the discounted expected reward criterion, especially, the condition \\beta = 1 indicating the optimality of the greedy policy under the average accumulative reward criterion. Thus, the standard form of reward function can easily be used to judge the optimality of the greed...

  12. Functional changes in the reward circuit in response to gaming-related cues after training with a commercial video game.

    Science.gov (United States)

    Gleich, Tobias; Lorenz, Robert C; Gallinat, Jürgen; Kühn, Simone

    2017-03-16

    In the present longitudinal study, we aimed to investigate video game training associated neuronal changes in reward processing using functional magnetic resonance imaging (fMRI). We recruited 48 healthy young participants which were assigned to one of 2 groups: A group in which participants were instructed to play a commercial video game ("Super Mario 64 DS") on a portable Nintendo DS handheld console at least 30minutes a day over a period of two months (video gaming group; VG) or to a matched passive control group (CG). Before and after the training phase, in both groups, fMRI imaging was conducted during passively viewing reward and punishment-related videos sequences recorded from the trained video game. The results show that video game training may lead to reward related decrease in neuronal activation in the dorsolateral prefrontal cortex (DLPFC) and increase in the hippocampus. Additionally, the decrease in DLPFC activation was associated with gaming related parameters experienced during playing. Specifically, we found that in in the VG, gaming related parameters like performance, experienced fun and frustration (assessed during the training period) were correlated to decrease in reward related DLPFC activity. Thus, neuronal changes in terms of video game training seem to be highly related to the appetitive character and reinforcement schedule of the game. Those neuronal changes may also be related to the often reported video game associated improvements in cognitive functions.

  13. Strengthening connections: functional connectivity and brain plasticity

    OpenAIRE

    2014-01-01

    The ascendancy of functional neuroimaging has facilitated the addition of network-based approaches to the neuropsychologist’s toolbox for evaluating the sequelae of brain insult. In particular, intrinsic functional connectivity (iFC) mapping of resting state fMRI (R-fMRI) data constitutes an ideal approach to measuring macro-scale networks in the human brain. Beyond the value of iFC mapping for charting how the functional topography of the brain is altered by insult and injury, iFC analyses c...

  14. Altered functional brain networks in Prader-Willi syndrome.

    Science.gov (United States)

    Zhang, Yi; Zhao, Heng; Qiu, Siyou; Tian, Jie; Wen, Xiaotong; Miller, Jennifer L; von Deneen, Karen M; Zhou, Zhenyu; Gold, Mark S; Liu, Yijun

    2013-06-01

    Prader-Willi syndrome (PWS) is a genetic imprinting disorder characterized mainly by hyperphagia and early childhood obesity. Previous functional neuroimaging studies used visual stimuli to examine abnormal activities in the eating-related neural circuitry of patients with PWS. It was found that patients with PWS exhibited both excessive hunger and hyperphagia consistently, even in situations without any food stimulation. In the present study, we employed resting-state functional MRI techniques to investigate abnormal brain networks related to eating disorders in children with PWS. First, we applied amplitude of low-frequency fluctuation analysis to define the regions of interest that showed significant alterations in resting-state brain activity levels in patients compared with their sibling control group. We then applied a functional connectivity (FC) analysis to these regions of interest in order to characterize interactions among the brain regions. Our results demonstrated that patients with PWS showed decreased FC strength in the medial prefrontal cortex (MPFC)/inferior parietal lobe (IPL), MPFC/precuneus, IPL/precuneus and IPL/hippocampus in the default mode network; decreased FC strength in the pre-/postcentral gyri and dorsolateral prefrontal cortex (DLPFC)/orbitofrontal cortex (OFC) in the motor sensory network and prefrontal cortex network, respectively; and increased FC strength in the anterior cingulate cortex/insula, ventrolateral prefrontal cortex (VLPFC)/OFC and DLPFC/VLPFC in the core network and prefrontal cortex network, respectively. These findings indicate that there are FC alterations among the brain regions implicated in eating as well as rewarding, even during the resting state, which may provide further evidence supporting the use of PWS as a model to study obesity and to provide information on potential neural targets for the medical treatment of overeating.

  15. Simple models of human brain functional networks.

    Science.gov (United States)

    Vértes, Petra E; Alexander-Bloch, Aaron F; Gogtay, Nitin; Giedd, Jay N; Rapoport, Judith L; Bullmore, Edward T

    2012-04-10

    Human brain functional networks are embedded in anatomical space and have topological properties--small-worldness, modularity, fat-tailed degree distributions--that are comparable to many other complex networks. Although a sophisticated set of measures is available to describe the topology of brain networks, the selection pressures that drive their formation remain largely unknown. Here we consider generative models for the probability of a functional connection (an edge) between two cortical regions (nodes) separated by some Euclidean distance in anatomical space. In particular, we propose a model in which the embedded topology of brain networks emerges from two competing factors: a distance penalty based on the cost of maintaining long-range connections; and a topological term that favors links between regions sharing similar input. We show that, together, these two biologically plausible factors are sufficient to capture an impressive range of topological properties of functional brain networks. Model parameters estimated in one set of functional MRI (fMRI) data on normal volunteers provided a good fit to networks estimated in a second independent sample of fMRI data. Furthermore, slightly detuned model parameters also generated a reasonable simulation of the abnormal properties of brain functional networks in people with schizophrenia. We therefore anticipate that many aspects of brain network organization, in health and disease, may be parsimoniously explained by an economical clustering rule for the probability of functional connectivity between different brain areas.

  16. Markov reward processes

    Science.gov (United States)

    Smith, R. M.

    1991-01-01

    Numerous applications in the area of computer system analysis can be effectively studied with Markov reward models. These models describe the behavior of the system with a continuous-time Markov chain, where a reward rate is associated with each state. In a reliability/availability model, upstates may have reward rate 1 and down states may have reward rate zero associated with them. In a queueing model, the number of jobs of certain type in a given state may be the reward rate attached to that state. In a combined model of performance and reliability, the reward rate of a state may be the computational capacity, or a related performance measure. Expected steady-state reward rate and expected instantaneous reward rate are clearly useful measures of the Markov reward model. More generally, the distribution of accumulated reward or time-averaged reward over a finite time interval may be determined from the solution of the Markov reward model. This information is of great practical significance in situations where the workload can be well characterized (deterministically, or by continuous functions e.g., distributions). The design process in the development of a computer system is an expensive and long term endeavor. For aerospace applications the reliability of the computer system is essential, as is the ability to complete critical workloads in a well defined real time interval. Consequently, effective modeling of such systems must take into account both performance and reliability. This fact motivates our use of Markov reward models to aid in the development and evaluation of fault tolerant computer systems.

  17. Neuroenergetics: How energy constraints shape brain function

    CERN Document Server

    CERN. Geneva

    2016-01-01

    The nervous system consumes a disproportionate fraction of the resting body’s energy production. In humans, the brain represents 2% of the body’s mass, yet it accounts for ~20% of the total oxygen consumption. Expansion in the size of the brain relative to the body and an increase in the number of connections between neurons during evolution underpin our cognitive powers and are responsible for our brains’ high metabolic rate. The molecules at the center of cellular energy metabolism also act as intercellular signals and constitute an important communication pathway, coordinating for instance the immune surveillance of the brain. Despite the significance of energy consumption in the nervous system, how energy constrains and shapes brain function is often under appreciated. I will illustrate the importance of brain energetics and metabolism with two examples from my recent work. First, I will show how the brain trades information for energy savings in the visual pathway. Indeed, a significant fraction ...

  18. Neural dissociation of food- and money-related reward processing using an abstract incentive delay task.

    Science.gov (United States)

    Simon, Joe J; Skunde, Mandy; Wu, Mudan; Schnell, Knut; Herpertz, Sabine C; Bendszus, Martin; Herzog, Wolfgang; Friederich, Hans-Christoph

    2015-08-01

    Food is an innate reward stimulus related to energy homeostasis and survival, whereas money is considered a more general reward stimulus that gains a rewarding value through learning experiences. Although the underlying neural processing for both modalities of reward has been investigated independently from one another, a more detailed investigation of neural similarities and/or differences between food and monetary reward is still missing. Here, we investigated the neural processing of food compared with monetary-related rewards in 27 healthy, normal-weight women using functional magnetic resonance imaging. We developed a task distinguishing between the anticipation and the receipt of either abstract food or monetary reward. Both tasks activated the ventral striatum during the expectation of a reward. Compared with money, greater food-related activations were observed in prefrontal, parietal and central midline structures during the anticipation and lateral orbitofrontal cortex (lOFC) during the receipt of food reward. Furthermore, during the receipt of food reward, brain activation in the secondary taste cortex was positively related to the body mass index. These results indicate that food-dependent activations encompass to a greater extent brain regions involved in self-control and self-reflection during the anticipation and phylogenetically older parts of the lOFC during the receipt of reward.

  19. Functional changes of the reward system underlie blunted response to social gaze in cocaine users

    OpenAIRE

    Preller, K H; Herdener, M; Quednow, B. B.; Schilbach, L.; Stampfli, P.; Hulka, L. M.; Vonmoos, M.; Ingold, N.; Vogeley, K.; Tobler, P N; Seifritz, E.

    2014-01-01

    Social interaction deficits in drug users likely impede treatment, increase the burden of the affected families, and consequently contribute to the high costs for society associated with addiction. Despite its significance, the neural basis of altered social interaction in drug users is currently unknown. Therefore, we investigated basal social gaze behavior in cocaine users by applying behavioral, psychophysiological, and functional brain-imaging methods. In study I, 80 regular cocaine users...

  20. Functional states of rat cortical circuits during the unpredictable availability of a reward-related cue.

    Science.gov (United States)

    Fernández-Lamo, Iván; Sánchez-Campusano, Raudel; Gruart, Agnès; Delgado-García, José M

    2016-11-21

    Proper performance of acquired abilities can be disturbed by the unexpected occurrence of external changes. Rats trained with an operant conditioning task (to press a lever in order to obtain a food pellet) using a fixed-ratio (1:1) schedule were subsequently placed in a Skinner box in which the lever could be removed randomly. Field postsynaptic potentials (fPSPs) were chronically evoked in perforant pathway-hippocampal CA1 (PP-CA1), CA1-subiculum (CA1-SUB), CA1-medial prefrontal cortex (CA1-mPFC), mPFC-nucleus accumbens (mPFC-NAc), and mPFC-basolateral amygdala (mPFC-BLA) synapses during lever IN and lever OUT situations. While lever presses were accompanied by a significant increase in fPSP slopes at the five synapses, the unpredictable absence of the lever were accompanied by decreased fPSP slopes in all, except PP-CA1 synapses. Spectral analysis of local field potentials (LFPs) recorded when the animal approached the corresponding area in the lever OUT situation presented lower spectral powers than during lever IN occasions for all recording sites, apart from CA1. Thus, the unpredictable availability of a reward-related cue modified the activity of cortical and subcortical areas related with the acquisition of operant learning tasks, suggesting an immediate functional reorganization of these neural circuits to address the changed situation and to modify ongoing behaviors accordingly.

  1. Forthergillian Lecture. Imaging human brain function.

    Science.gov (United States)

    Frackowiak, R S

    The non-invasive brain scanning techniques introduced a quarter of a century ago have become crucial for diagnosis in clinical neurology. They have also been used to investigate brain function and have provided information about normal activity and pathogenesis. They have been used to investigate functional specialization in the brain and how specialized areas communicate to generate complex integrated functions such as speech, memory, the emotions and so on. The phenomenon of brain plasticity is poorly understood and yet clinical neurologists are aware, from everyday observations, that spontaneous recovery from brain lesions is common. An improved understanding of the mechanisms of recovery may generate new therapeutic strategies and indicate ways of modulating mechanisms that promote plastic compensation for loss of function. The main methods used to investigate these issues are positron emission tomography and magnetic resonance imaging (M.R.I.). M.R.I. is also used to map brain structure. The techniques of functional brain mapping and computational morphometrics depend on high performance scanners and a validated set of analytic statistical procedures that generate reproducible data and meaningful inferences from brain scanning data. The motor system presents a good paradigm to illustrate advances made by scanning towards an understanding of plasticity at the level of brain areas. The normal motor system is organized in a nested hierarchy. Recovery from paralysis caused by internal capsule strokes involves functional reorganization manifesting itself as changed patterns of activity in the component brain areas of the normal motor system. The pattern of plastic modification depends in part on patterns of residual or disturbed connectivity after brain injury. Therapeutic manipulations in patients with Parkinson's disease using deep brain stimulation, dopaminergic agents or fetal mesencephalic transplantation provide a means to examine mechanisms underpinning

  2. Functional network organization of the human brain.

    Science.gov (United States)

    Power, Jonathan D; Cohen, Alexander L; Nelson, Steven M; Wig, Gagan S; Barnes, Kelly Anne; Church, Jessica A; Vogel, Alecia C; Laumann, Timothy O; Miezin, Fran M; Schlaggar, Bradley L; Petersen, Steven E

    2011-11-17

    Real-world complex systems may be mathematically modeled as graphs, revealing properties of the system. Here we study graphs of functional brain organization in healthy adults using resting state functional connectivity MRI. We propose two novel brain-wide graphs, one of 264 putative functional areas, the other a modification of voxelwise networks that eliminates potentially artificial short-distance relationships. These graphs contain many subgraphs in good agreement with known functional brain systems. Other subgraphs lack established functional identities; we suggest possible functional characteristics for these subgraphs. Further, graph measures of the areal network indicate that the default mode subgraph shares network properties with sensory and motor subgraphs: it is internally integrated but isolated from other subgraphs, much like a "processing" system. The modified voxelwise graph also reveals spatial motifs in the patterning of systems across the cortex.

  3. Physiological functions of brain metallothionein

    Energy Technology Data Exchange (ETDEWEB)

    Yasutake, Akira [National Inst. for Minamata Disease, Kumamoto (Japan)

    2000-02-01

    It has been known that the brain has a certain kind of metallothinein (MT)-3 that has not been found in other tissues.This evidence is only based on the data of mRNA level. In this study, isolation method and quantification method which allows specific determination of MT-3 were developed. The cerebrum and cerebellum were removed from rats exposed to mercury vapor for 24 hours to induce MT-3 and Hg concentration, which reflects the concentration of MT-3 in their supernatants was determined. Then, each supernatant was applied onto FPLC column chromatography and Hg concentration of each fraction was determined. Since the molecular weight of MT-3 was slightly larger than MT-1, MT-2, its isolation was conducted using gel filtration chromatography. When the two columns were linked, MT-3 obtained from the brain of MT-null mouse and MT-1/2 from the kidney of wild mouse could be isolated without any overlapping and it was indicated that the larger MT-3 was eluted in a fraction earlier than the others. Whereas for Hg-MT sample from wild mouse brain, which includes all MT isomers, there appeared two peaks corresponding to MT-3 and MT-1/2, respectively, showing that isolation and quantification of MT-3 using a linked column were possible. It was demonstrated that MT-3 occupies 70-80% of the total amount of MT in wild mouse brain and the total amount in the MT-null brain was about 80% of that of the wild. Therefore, the absolute amount of MT- 3 was thought to be not different between the wild and MT-null mouse. Since detection threshold of Hg for this apparatus was 0.2 ng (1 pmole), that for MT was estimated to be 0.1 pmole because 10 Hg atoms are bound to one MT. Therefore, it is thought the sensitivity of this method is higher than that of UV detection method. (M.N.)

  4. Scale-Free Brain Functional Networks

    Science.gov (United States)

    Eguíluz, Victor M.; Chialvo, Dante R.; Cecchi, Guillermo A.; Baliki, Marwan; Apkarian, A. Vania

    2005-01-01

    Functional magnetic resonance imaging is used to extract functional networks connecting correlated human brain sites. Analysis of the resulting networks in different tasks shows that (a)the distribution of functional connections, and the probability of finding a link versus distance are both scale-free, (b)the characteristic path length is small and comparable with those of equivalent random networks, and (c)the clustering coefficient is orders of magnitude larger than those of equivalent random networks. All these properties, typical of scale-free small-world networks, reflect important functional information about brain states.

  5. Promoting Motor Function by Exercising the Brain

    Directory of Open Access Journals (Sweden)

    Stephane Perrey

    2013-01-01

    Full Text Available Exercise represents a behavioral intervention that enhances brain health and motor function. The increase in cerebral blood volume in response to physical activity may be responsible for improving brain function. Among the various neuroimaging techniques used to monitor brain hemodynamic response during exercise, functional near-infrared spectroscopy could facilitate the measurement of task-related cortical responses noninvasively and is relatively robust with regard to the subjects’ motion. Although the components of optimal exercise interventions have not been determined, evidence from animal and human studies suggests that aerobic exercise with sufficiently high intensity has neuroprotective properties and promotes motor function. This review provides an insight into the effect of physical activity (based on endurance and resistance exercises on brain function for producing movement. Since most progress in the study of brain function has come from patients with neurological disorders (e.g., stroke and Parkinson’s patients, this review presents some findings emphasizing training paradigms for restoring motor function.

  6. How the brain represents the reward value of fat in the mouth.

    OpenAIRE

    Grabenhorst, Fabian; Rolls, Edmund T.; Parris, Benjamin; De Souza, Arun

    2009-01-01

    The palatability and pleasantness of the sensory properties of foods drive food selection and intake and may contribute to overeating and obesity. Oral fat texture can make food palatable and pleasant. To analyze its neural basis, we correlated humans’ subjective reports of the pleasantness of the texture and flavor of a high- and low-fat food with a vanilla or strawberry flavor, with neural activations measured with functional magnetic resonance imaging. Activity in the midorbitofrontal and ...

  7. Food reward in the absence of taste receptor signaling.

    Science.gov (United States)

    de Araujo, Ivan E; Oliveira-Maia, Albino J; Sotnikova, Tatyana D; Gainetdinov, Raul R; Caron, Marc G; Nicolelis, Miguel A L; Simon, Sidney A

    2008-03-27

    Food palatability and hedonic value play central roles in nutrient intake. However, postingestive effects can influence food preferences independently of palatability, although the neurobiological bases of such mechanisms remain poorly understood. Of central interest is whether the same brain reward circuitry that is responsive to palatable rewards also encodes metabolic value independently of taste signaling. Here we show that trpm5-/- mice, which lack the cellular machinery required for sweet taste transduction, can develop a robust preference for sucrose solutions based solely on caloric content. Sucrose intake induced dopamine release in the ventral striatum of these sweet-blind mice, a pattern usually associated with receipt of palatable rewards. Furthermore, single neurons in this same ventral striatal region showed increased sensitivity to caloric intake even in the absence of gustatory inputs. Our findings suggest that calorie-rich nutrients can directly influence brain reward circuits that control food intake independently of palatability or functional taste transduction.

  8. From functional genomics to functional immunomics: new challenges, old problems, big rewards.

    Directory of Open Access Journals (Sweden)

    Ulisses M Braga-Neto

    2006-07-01

    Full Text Available The development of DNA microarray technology a decade ago led to the establishment of functional genomics as one of the most active and successful scientific disciplines today. With the ongoing development of immunomic microarray technology-a spatially addressable, large-scale technology for measurement of specific immunological response-the new challenge of functional immunomics is emerging, which bears similarities to but is also significantly different from functional genomics. Immunonic data has been successfully used to identify biological markers involved in autoimmune diseases, allergies, viral infections such as human immunodeficiency virus (HIV, influenza, diabetes, and responses to cancer vaccines. This review intends to provide a coherent vision of this nascent scientific field, and speculate on future research directions. We discuss at some length issues such as epitope prediction, immunomic microarray technology and its applications, and computation and statistical challenges related to functional immunomics. Based on the recent discovery of regulation mechanisms in T cell responses, we envision the use of immunomic microarrays as a tool for advances in systems biology of cellular immune responses, by means of immunomic regulatory network models.

  9. [Brain mechanisms of male sexual function].

    Science.gov (United States)

    Wang, Ying; Dou, Xin; Li, Jun-Fa; Luo, Yan-Lin

    2011-08-01

    In this paper, we reviewed the brain imaging studies of male sexual function in recent years from three aspects: the brain mechanism of normal sexual function, the brain mechanism of sexual dysfunction, and the mechanism of drug therapy for sexual dysfunction. Studies show that the development stages of male sexual activities, such as the excitement phase, plateau phase and orgasm phase, are controlled by different neural networks. The mesodiencephalic transition zone may play an important role in the start up of male ejaculation. There are significant differences between sexual dysfunction males and normal males in activation patterns of the brain in sexual arousal. The medial orbitofrontal cortex and inferior frontal gyrus in the abnormal activation pattern are correlated with sexual dysfunction males in sexual arousal. Serum testosterone and morphine are commonly used drugs for male sexual dysfunction, whose mechanisms are to alter the activating levels of the medial orbitofrontal cortex, insula, claustrum and inferior temporal gyrus.

  10. Dysregulation of brain reward systems in eating disorders: neurochemical information from animal models of binge eating, bulimia nervosa, and anorexia nervosa.

    Science.gov (United States)

    Avena, Nicole M; Bocarsly, Miriam E

    2012-07-01

    Food intake is mediated, in part, through brain pathways for motivation and reinforcement. Dysregulation of these pathways may underlay some of the behaviors exhibited by patients with eating disorders. Research using animal models of eating disorders has greatly contributed to the detailed study of potential brain mechanisms that many underlie the causes or consequences of aberrant eating behaviors. This review focuses on neurochemical evidence of reward-related brain dysfunctions obtained through animal models of binge eating, bulimia nervosa, or anorexia nervosa. The findings suggest that alterations in dopamine (DA), acetylcholine (ACh) and opioid systems in reward-related brain areas occur in response to binge eating of palatable foods. Moreover, animal models of bulimia nervosa suggest that while bingeing on palatable food releases DA, purging attenuates the release of ACh that might otherwise signal satiety. Animal models of anorexia nervosa suggest that restricted access to food enhances the reinforcing effects of DA when the animal does eat. The activity-based anorexia model suggests alterations in mesolimbic DA and serotonin occur as a result of restricted eating coupled with excessive wheel running. These findings with animal models complement data obtained through neuroimaging and pharmacotherapy studies of clinical populations. Information on the neurochemical consequences of the behaviors associated with these eating disorders will be useful in understanding these complex disorders and may inform future therapeutic approaches, as discussed here. This article is part of a Special Issue entitled 'Central Control of Food Intake'.

  11. Exercise Benefits Brain Function: The Monoamine Connection

    OpenAIRE

    Tzu-Wei Lin; Yu-Min Kuo

    2013-01-01

    The beneficial effects of exercise on brain function have been demonstrated in animal models and in a growing number of clinical studies on humans. There are multiple mechanisms that account for the brain-enhancing effects of exercise, including neuroinflammation, vascularization, antioxidation, energy adaptation, and regulations on neurotrophic factors and neurotransmitters. Dopamine (DA), noradrenaline (NE), and serotonin (5-HT) are the three major monoamine neurotransmitters that are known...

  12. 5-HT receptors and reward-related behaviour: a review.

    Science.gov (United States)

    Hayes, Dave J; Greenshaw, Andrew J

    2011-05-01

    The brain's serotonin (5-HT) system is key in the regulation of reward-related behaviours, from eating and drinking to sexual activity. The complexity of studying this system is due, in part, to the fact that 5-HT acts at many receptor subtypes throughout the brain. The recent development of drugs with greater selectivity for individual receptor subtypes has allowed for rapid advancements in our understanding of this system. Use of these drugs in combination with animal models entailing selective reward measures (i.e. intracranial self-stimulation, drug self-administration, conditioned place preference) have resulted in a greater understanding of the pharmacology of reward-related processing and behaviour (particularly regarding drugs of abuse). The putative roles of each 5-HT receptor subtype in the pharmacology of reward are outlined and discussed here. It is concluded that the actions of 5-HT in reward are receptor subtype-dependent (and thus should not be generalized) and that all studied subtypes appear to have a unique profile which is determined by content (e.g. receptor function, localization - both throughout the brain and within the synapse) and context (e.g. type of behavioural paradigm, type of drug). Given evidence of altered reward-related processing and serotonergic function in numerous neuropsychiatric disorders, such as depression, schizophrenia, and addiction, a clearer understanding of the role of 5-HT receptor subtypes in this context may lead to improved drug development and therapeutic approaches.

  13. Executive Functioning after Traumatic Brain Injury

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2008-07-01

    Full Text Available The Behavior Rating Inventory of Executive Function (BRIEF, a caregiver-report questionnaire, was used to measure changes in executive function in the first year after traumatic brain injury (TBI in a study of children, aged 5 to 15 years, at University of Minnesota, Minneapolis, and Johns Hopkins University School of Medicine, Baltimore, MD.

  14. Toward discovery science of human brain function.

    NARCIS (Netherlands)

    Biswal, B.B.; Mennes, M.; Zuo, X.N.; Gohel, S.; Kelly, C.; Smith, S.M.; Beckmann, C.F.; Adelstein, J.S.; Buckner, R.L.; Colcombe, S.; Dogonowski, A.M.; Ernst, M.; Fair, D.; Hampson, M.; Hoptman, M.J.; Hyde, J.S.; Kiviniemi, V.J.; Kotter, R.; Li, S.J.; Lin, C.P.; Lowe, M.J.; Mackay, C.; Madden, D.J.; Madsen, K.H.; Margulies, D.S.; Mayberg, H.S.; McMahon, K.; Monk, C.S.; Mostofsky, S.H.; Nagel, B.J.; Pekar, J.J.; Peltier, S.J.; Petersen, S.E.; Riedl, V.; Rombouts, S.A.; Rypma, B.; Schlaggar, B.L.; Schmidt, S.; Seidler, R.D.; Siegle, G.J.; Sorg, C.; Teng, G.J.; Veijola, J.; Villringer, A.; Walter, M.; Wang, L.; Weng, X.C.; Whitfield-Gabrieli, S.; Williamson, P.; Windischberger, C.; Zang, Y.F.; Zhang, H.Y.; Castellanos, F.X.; Milham, M.P.

    2010-01-01

    Although it is being successfully implemented for exploration of the genome, discovery science has eluded the functional neuroimaging community. The core challenge remains the development of common paradigms for interrogating the myriad functional systems in the brain without the constraints of a pr

  15. Prediction of alcohol drinking in adolescents: Personality-traits, behavior, brain responses, and genetic variations in the context of reward sensitivity.

    Science.gov (United States)

    Heinrich, Angela; Müller, Kathrin U; Banaschewski, Tobias; Barker, Gareth J; Bokde, Arun L W; Bromberg, Uli; Büchel, Christian; Conrod, Patricia; Fauth-Bühler, Mira; Papadopoulos, Dimitri; Gallinat, Jürgen; Garavan, Hugh; Gowland, Penny; Heinz, Andreas; Ittermann, Bernd; Mann, Karl; Martinot, Jean-Luc; Paus, Tomáš; Pausova, Zdenka; Smolka, Michael; Ströhle, Andreas; Rietschel, Marcella; Flor, Herta; Schumann, Gunter; Nees, Frauke

    2016-07-01

    Adolescence is a time that can set the course of alcohol abuse later in life. Sensitivity to reward on multiple levels is a major factor in this development. We examined 736 adolescents from the IMAGEN longitudinal study for alcohol drinking during early (mean age=14.37) and again later (mean age=16.45) adolescence. Conducting structural equation modeling we evaluated the contribution of reward-related personality traits, behavior, brain responses and candidate genes. Personality seems to be most important in explaining alcohol drinking in early adolescence. However, genetic variations in ANKK1 (rs1800497) and HOMER1 (rs7713917) play an equal role in predicting alcohol drinking two years later and are most important in predicting the increase in alcohol consumption. We hypothesize that the initiation of alcohol use may be driven more strongly by personality while the transition to increased alcohol use is more genetically influenced.

  16. Prospects for optogenetic augmentation of brain function

    Directory of Open Access Journals (Sweden)

    Sarah eJarvis

    2015-11-01

    Full Text Available The ability to optically control neural activity opens up possibilities for the restoration of normal function following neurological disorders. The temporal precision, spatial resolution and neuronal specificity that optogenetics offers is unequalled by other available methods, so will it be suitable for not only restoring but also extending brain function? As the first demonstrations of optically ``implanted'' novel memories emerge, we examine the suitability of optogenetics as a technique for extending neural function. While optogenetics is an effective tool for altering neural activity, the largest impediment for optogenetics in neural augmentation is our systems level understanding of brain function. Furthermore, a number of clinical limitations currently remain as substantial hurdles for the applications proposed. While neurotechnologies for treating brain disorders and interfacing with prosthetics have advanced rapidly in the past few years, partially addressing some of these critical problems, optogenetics is not yet suitable for use in humans. Instead we conclude that for the immediate future, optogenetics is the neurological equivalent of the 3D printer: its flexibility providing an ideal tool for testing and prototyping solutions for treating brain disorders and augmenting brain function.

  17. Left Hemispheric Imbalance and Reward Mechanisms Affect Gambling Behavior: The Contribution of the Metacognition and Cortical Brain Oscillations.

    Science.gov (United States)

    Balconi, Michela; Finocchiaro, Roberta; Canavesio, Ylenia

    2015-07-01

    The present research used the Iowa Gambling Task to test the effect of the reward-sensitivity Behavioral Activation System-Reward (BAS-Reward) construct on the ability to distinguish between high- and low-risk decisions. To elucidate the individual differences that influence the decisional processes, making the strategies more or less advantageous, we considered the impact of the BAS motivational system and the frontal left and right cortical activity on subjects' decisions. More specifically, the lateralization effect, which is related to the increased activation of the left (BAS-Reward-related) hemisphere, was explored by using frequency band analysis. Specifically, behavioral responses (gain/loss options), metacognition, and delta, theta, alpha, and beta band modulation (asymmetry index) were considered. Thirty subjects were divided into high-BAS and low-BAS groups. In comparison with low-BAS, the high-BAS group showed an increased tendency to opt in favor of the immediate reward (losing strategy) instead of the long-term option (winning strategy), and members of this group were more impaired in metacognitive monitoring of their strategies and showed an increased left hemisphere activation when they responded to losing choices. A "reward bias" effect was hypothesized to act for high BAS, based on a left-hemisphere hyperactivation.

  18. Functional brain network efficiency predicts intelligence.

    Science.gov (United States)

    Langer, Nicolas; Pedroni, Andreas; Gianotti, Lorena R R; Hänggi, Jürgen; Knoch, Daria; Jäncke, Lutz

    2012-06-01

    The neuronal causes of individual differences in mental abilities such as intelligence are complex and profoundly important. Understanding these abilities has the potential to facilitate their enhancement. The purpose of this study was to identify the functional brain network characteristics and their relation to psychometric intelligence. In particular, we examined whether the functional network exhibits efficient small-world network attributes (high clustering and short path length) and whether these small-world network parameters are associated with intellectual performance. High-density resting state electroencephalography (EEG) was recorded in 74 healthy subjects to analyze graph-theoretical functional network characteristics at an intracortical level. Ravens advanced progressive matrices were used to assess intelligence. We found that the clustering coefficient and path length of the functional network are strongly related to intelligence. Thus, the more intelligent the subjects are the more the functional brain network resembles a small-world network. We further identified the parietal cortex as a main hub of this resting state network as indicated by increased degree centrality that is associated with higher intelligence. Taken together, this is the first study that substantiates the neural efficiency hypothesis as well as the Parieto-Frontal Integration Theory (P-FIT) of intelligence in the context of functional brain network characteristics. These theories are currently the most established intelligence theories in neuroscience. Our findings revealed robust evidence of an efficiently organized resting state functional brain network for highly productive cognitions.

  19. Value and probability coding in a feedback-based learning task utilizing food rewards.

    Science.gov (United States)

    Tricomi, Elizabeth; Lempert, Karolina M

    2015-01-01

    For the consequences of our actions to guide behavior, the brain must represent different types of outcome-related information. For example, an outcome can be construed as negative because an expected reward was not delivered or because an outcome of low value was delivered. Thus behavioral consequences can differ in terms of the information they provide about outcome probability and value. We investigated the role of the striatum in processing probability-based and value-based negative feedback by training participants to associate cues with food rewards and then employing a selective satiety procedure to devalue one food outcome. Using functional magnetic resonance imaging, we examined brain activity related to receipt of expected rewards, receipt of devalued outcomes, omission of expected rewards, omission of devalued outcomes, and expected omissions of an outcome. Nucleus accumbens activation was greater for rewarding outcomes than devalued outcomes, but activity in this region did not correlate with the probability of reward receipt. Activation of the right caudate and putamen, however, was largest in response to rewarding outcomes relative to expected omissions of reward. The dorsal striatum (caudate and putamen) at the time of feedback also showed a parametric increase correlating with the trialwise probability of reward receipt. Our results suggest that the ventral striatum is sensitive to the motivational relevance, or subjective value, of the outcome, while the dorsal striatum codes for a more complex signal that incorporates reward probability. Value and probability information may be integrated in the dorsal striatum, to facilitate action planning and allocation of effort.

  20. Motivational orientation modulates the neural response to reward.

    Science.gov (United States)

    Linke, Julia; Kirsch, Peter; King, Andrea V; Gass, Achim; Hennerici, Michael G; Bongers, André; Wessa, Michèle

    2010-02-01

    Motivational orientation defines the source of motivation for an individual to perform a particular action and can either originate from internal desires (e.g., interest) or external compensation (e.g., money). To this end, motivational orientation should influence the way positive or negative feedback is processed during learning situations and this might in turn have an impact on the learning process. In the present study, we thus investigated whether motivational orientation, i.e., extrinsic and intrinsic motivation modulates the neural response to reward and punishment as well as learning from reward and punishment in 33 healthy individuals. To assess neural responses to reward, punishment and learning of reward contingencies we employed a probabilistic reversal learning task during functional magnetic resonance imaging. Extrinsic and intrinsic motivation were assessed with a self-report questionnaire. Rewarding trials fostered activation in the medial orbitofrontal cortex and anterior cingulate gyrus (ACC) as well as the amygdala and nucleus accumbens, whereas for punishment an increased neural response was observed in the medial and inferior prefrontal cortex, the superior parietal cortex and the insula. High extrinsic motivation was positively correlated to increased neural responses to reward in the ACC, amygdala and putamen, whereas a negative relationship between intrinsic motivation and brain activation in these brain regions was observed. These findings show that motivational orientation indeed modulates the responsiveness to reward delivery in major components of the human reward system and therefore extends previous results showing a significant influence of individual differences in reward-related personality traits on the neural processing of reward.

  1. Advantages in functional imaging of the brain

    Directory of Open Access Journals (Sweden)

    Walter eMier

    2015-05-01

    Full Text Available As neuronal pathologies cause only minor morphological alterations, molecular imaging techniques are a prerequisite for the study of diseases of the brain. The development of molecular probes that specifically bind biochemical markers and the advances of instrumentation have revolutionized the possibilities to gain insight into the human brain organization and beyond this visualize structure-function and brain-behavior relationships. The review describes the development and current applications of functional brain imaging techniques with a focus on applications in psychiatry. A historical overview of the development of functional imaging is followed by the portrayal of the principles and applications of positron emission tomography (PET and functional magnetic resonance imaging (fMRI, two key molecular imaging techniques that have revolutionized the ability to image molecular processes in the brain. In the juxtaposition of PET and fMRI in hybrid PET/MRI scanners enhances the significance of both modalities for research in neurology and psychiatry and might pave the way for a new area of personalized medicine.

  2. Strengthening connections: functional connectivity and brain plasticity.

    Science.gov (United States)

    Kelly, Clare; Castellanos, F Xavier

    2014-03-01

    The ascendancy of functional neuroimaging has facilitated the addition of network-based approaches to the neuropsychologist's toolbox for evaluating the sequelae of brain insult. In particular, intrinsic functional connectivity (iFC) mapping of resting state fMRI (R-fMRI) data constitutes an ideal approach to measuring macro-scale networks in the human brain. Beyond the value of iFC mapping for charting how the functional topography of the brain is altered by insult and injury, iFC analyses can provide insights into experience-dependent plasticity at the macro level of large-scale functional networks. Such insights are foundational to the design of training and remediation interventions that will best facilitate recovery of function. In this review, we consider what is currently known about the origin and function of iFC in the brain, and how this knowledge is informative in neuropsychological settings. We then summarize studies that have examined experience-driven plasticity of iFC in healthy control participants, and frame these findings in terms of a schema that may aid in the interpretation of results and the generation of hypotheses for rehabilitative studies. Finally, we outline some caveats to the R-fMRI approach, as well as some current developments that are likely to bolster the utility of the iFC paradigm for neuropsychology.

  3. Visceral Afferent Pathways and Functional Brain Imaging

    Directory of Open Access Journals (Sweden)

    Stuart W.G. Derbyshire

    2003-01-01

    Full Text Available The application of functional imaging to study painful sensations has generated considerable interest regarding insight into brain dysfunction that may be responsible for functional pain such as that suffered in patients with irritable bowel syndrome (IBS. This review provides a brief introduction to the development of brain science as it relates to pain processing and a snapshot of recent functional imaging results with somatic and visceral pain. Particular emphasis is placed on current hypotheses regarding dysfunction of the brain-gut axis in IBS patients. There are clear and interpretable differences in brain activation following somatic as compared with visceral noxious sensation. Noxious visceral distension, particularly of the lower gastrointestinal tract, activates regions associated with unpleasant affect and autonomic responses. Noxious somatic sensation, in contrast, activates regions associated with cognition and skeletomotor responses. Differences between IBS patients and control subjects, however, were far less clear and interpretable. While this is in part due to the newness of this field, it also reflects weaknesses inherent within the current understanding of IBS. Future use of functional imaging to examine IBS and other functional disorders will be more likely to succeed by describing clear theoretical and clinical endpoints.

  4. Functional interrelationship of brain aging and delirium.

    Science.gov (United States)

    Rapazzini, Piero

    2016-02-01

    Theories on the development of delirium are complementary rather than competing and they may relate to each other. Here, we highlight that similar alterations in functional brain connectivity underlie both the observed age-related deficits and episodes of delirium. The default mode network (DMN) is a group of brain regions showing a greater level of activity at rest than during attention-based tasks. These regions include the posteromedial-anteromedial cortices and temporoparietal junctions. Evidence suggests that awareness is subserved through higher order neurons associated with the DMN. By using functional MRI disruption of DMN, connectivity and weaker task-induced deactivations of these regions are observed both in age-related cognitive impairment and during episodes of delirium. We can assume that an acute up-regulation of inhibitory tone within the brain acts to further disrupt network connectivity in vulnerable patients, who are predisposed by a reduced baseline connectivity, and triggers the delirium.

  5. Favorite brands as cultural objects modulate reward circuit.

    Science.gov (United States)

    Schaefer, Michael; Rotte, Michael

    2007-01-22

    On the basis of the hypothesis that brands may function as reward stimuli, we investigated brain responses to favorite brands. Participants viewed brand logos while we measured cortical activity with functional magnetic resonance imaging. Results revealed activity in the striatum for favorite brands that positively correlated with sports and luxury characteristics, but negatively with attributions to a brand of rational choice. Reduced activation of a single region in the dorsolateral prefrontal cortex was demonstrated when viewing the most beloved brand, possibly suggesting reduced strategic reasoning on the basis of affect. The results propose that brands that have been associated with appetitive stimuli owing to marketing efforts engage brain networks similar to those engaged by artificially associated reward stimuli. Moreover, social stimuli may function as secondary inducers of reward mechanisms.

  6. DHA Effects in Brain Development and Function.

    Science.gov (United States)

    Lauritzen, Lotte; Brambilla, Paolo; Mazzocchi, Alessandra; Harsløf, Laurine B S; Ciappolino, Valentina; Agostoni, Carlo

    2016-01-04

    Docosahexaenoic acid (DHA) is a structural constituent of membranes specifically in the central nervous system. Its accumulation in the fetal brain takes place mainly during the last trimester of pregnancy and continues at very high rates up to the end of the second year of life. Since the endogenous formation of DHA seems to be relatively low, DHA intake may contribute to optimal conditions for brain development. We performed a narrative review on research on the associations between DHA levels and brain development and function throughout the lifespan. Data from cell and animal studies justify the indication of DHA in relation to brain function for neuronal cell growth and differentiation as well as in relation to neuronal signaling. Most data from human studies concern the contribution of DHA to optimal visual acuity development. Accumulating data indicate that DHA may have effects on the brain in infancy, and recent studies indicate that the effect of DHA may depend on gender and genotype of genes involved in the endogenous synthesis of DHA. While DHA levels may affect early development, potential effects are also increasingly recognized during childhood and adult life, suggesting a role of DHA in cognitive decline and in relation to major psychiatric disorders.

  7. DHA Effects in Brain Development and Function

    Directory of Open Access Journals (Sweden)

    Lotte Lauritzen

    2016-01-01

    Full Text Available Docosahexaenoic acid (DHA is a structural constituent of membranes specifically in the central nervous system. Its accumulation in the fetal brain takes place mainly during the last trimester of pregnancy and continues at very high rates up to the end of the second year of life. Since the endogenous formation of DHA seems to be relatively low, DHA intake may contribute to optimal conditions for brain development. We performed a narrative review on research on the associations between DHA levels and brain development and function throughout the lifespan. Data from cell and animal studies justify the indication of DHA in relation to brain function for neuronal cell growth and differentiation as well as in relation to neuronal signaling. Most data from human studies concern the contribution of DHA to optimal visual acuity development. Accumulating data indicate that DHA may have effects on the brain in infancy, and recent studies indicate that the effect of DHA may depend on gender and genotype of genes involved in the endogenous synthesis of DHA. While DHA levels may affect early development, potential effects are also increasingly recognized during childhood and adult life, suggesting a role of DHA in cognitive decline and in relation to major psychiatric disorders.

  8. Hierarchical modularity in human brain functional networks

    CERN Document Server

    Meunier, D; Fornito, A; Ersche, K D; Bullmore, E T; 10.3389/neuro.11.037.2009

    2010-01-01

    The idea that complex systems have a hierarchical modular organization originates in the early 1960s and has recently attracted fresh support from quantitative studies of large scale, real-life networks. Here we investigate the hierarchical modular (or "modules-within-modules") decomposition of human brain functional networks, measured using functional magnetic resonance imaging (fMRI) in 18 healthy volunteers under no-task or resting conditions. We used a customized template to extract networks with more than 1800 regional nodes, and we applied a fast algorithm to identify nested modular structure at several hierarchical levels. We used mutual information, 0 < I < 1, to estimate the similarity of community structure of networks in different subjects, and to identify the individual network that is most representative of the group. Results show that human brain functional networks have a hierarchical modular organization with a fair degree of similarity between subjects, I=0.63. The largest 5 modules at ...

  9. CART in the brain of vertebrates: circuits, functions and evolution.

    Science.gov (United States)

    Subhedar, Nishikant K; Nakhate, Kartik T; Upadhya, Manoj A; Kokare, Dadasaheb M

    2014-04-01

    Cocaine- and amphetamine-regulated transcript peptide (CART) with its wide distribution in the brain of mammals has been the focus of considerable research in recent years. Last two decades have witnessed a steady rise in the information on the genes that encode this neuropeptide and regulation of its transcription and translation. CART is highly enriched in the hypothalamic nuclei and its relevance to energy homeostasis and neuroendocrine control has been understood in great details. However, the occurrence of this peptide in a range of diverse circuitries for sensory, motor, vegetative, limbic and higher cortical areas has been confounding. Evidence that CART peptide may have role in addiction, pain, reward, learning and memory, cognition, sleep, reproduction and development, modulation of behavior and regulation of autonomic nervous system are accumulating, but an integration has been missing. A steady stream of papers has been pointing at the therapeutic potentials of CART. The current review is an attempt at piecing together the fragments of available information, and seeks meaning out of the CART elements in their anatomical niche. We try to put together the CART containing neuronal circuitries that have been conclusively demonstrated as well as those which have been proposed, but need confirmation. With a view to finding out the evolutionary antecedents, we visit the CART systems in sub-mammalian vertebrates and seek the answer why the system is shaped the way it is. We enquire into the conservation of the CART system and appreciate its functional diversity across the phyla.

  10. Orbitofrontal reward sensitivity and impulsivity in adult attention deficit hyperactivity disorder.

    Science.gov (United States)

    Wilbertz, Gregor; van Elst, Ludger Tebartz; Delgado, Mauricio R; Maier, Simon; Feige, Bernd; Philipsen, Alexandra; Blechert, Jens

    2012-03-01

    Impulsivity symptoms of adult attention deficit hyperactivity disorder (ADHD) such as increased risk taking have been linked with impaired reward processing. Previous studies have focused on reward anticipation or on rewarded executive functioning tasks and have described a striatal hyporesponsiveness and orbitofrontal alterations in adult and adolescent ADHD. Passive reward delivery and its link to behavioral impulsivity are less well understood. To study this crucial aspect of reward processing we used functional magnetic resonance imaging (fMRI) combined with electrodermal assessment in male and female adult ADHD patients (N=28) and matched healthy control participants (N=28) during delivery of monetary and non-monetary rewards. Further, two behavioral tasks assessed risky decision making (game of dice task) and delay discounting. Results indicated that both groups activated ventral and dorsal striatum and the medial orbitofrontal cortex (mOFC) in response to high-incentive (i.e. monetary) rewards. A similar, albeit less strong activation pattern was found for low-incentive (i.e. non-monetary) rewards. Group differences emerged when comparing high and low incentive rewards directly: activation in the mOFC coded for the motivational change in reward delivery in healthy controls, but not ADHD patients. Additionally, this dysfunctional mOFC activity in patients correlated with risky decision making and delay discounting and was paralleled by physiological arousal. Together, these results suggest that the mOFC codes reward value and type in healthy individuals whereas this function is deficient in ADHD. The brain-behavior correlations suggest that this deficit might be related to behavioral impulsivity. Reward value processing difficulties in ADHD should be considered when assessing reward anticipation and emotional learning in research and applied settings.

  11. Phasic and tonic fluctuations in brain, muscle, and skin temperatures during motivated drinking behavior in rats: physiological correlates of motivation and reward.

    Science.gov (United States)

    Smirnov, Michael S; Kiyatkin, Eugene A

    2010-01-15

    Since brain metabolism is accompanied by heat production, measurement of brain temperature offers a method for assessing global alterations in metabolic neural activity. This approach, high-resolution (5-s bin) temperature recording from the nucleus accumbens (NAcc), temporal muscle, and facial skin, was used to study motivated drinking behavior in rats. Experienced animals were presented with a cup containing 5-ml of Coca-Cola(R) (Coke) beverage that resulted, within certain latencies, in initiation of a continuous chain of licking until all liquid was fully consumed. While cup presentation induced rapid, gradual NAcc temperature increase peaking at the start of drinking, temperatures slowly decreased during Coke consumption, but phasically increased again in the post-consumption period when rats were hyperactive, showing multiple interactions with an empty cup. Muscle temperatures followed a similar pattern, but the changes were weaker and delayed compared to those in the brain. Skin temperature rapidly dropped after cup presentation, steadily maintained at low levels during consumption, and slowly restored during the post-consumption period. Substitution of the expected Coke with either sugar-free Diet Coke(R) or water resulted in numerous drinking attempts but ultimately no consumption. During these tests, locomotor activation was much greater and more prolonged, brain and muscle temperatures increased monophasically, and their elevation was significantly greater than that with regular Coke tests. Food deprivation decreased drinking latencies, did not change the pattern of temperature fluctuations during Coke consumption, but temperature elevations were greater than in controls. Our data suggest sustained neural activation triggered by appetitive stimuli and associated with activational (seeking) aspects of appetitive motivated behavior. This seeking-related activation is rapidly ceased following consumption, suggesting this change as a neural correlate of

  12. The influence of brain death on liver function

    NARCIS (Netherlands)

    Olinga, Peter; Hoeven, Joost Alexander Boreas van der; Merema, M.T.; Freund, R.L.; Ploeg, R.J; Groothuis, Geny

    2005-01-01

    Background: In this study, we investigated the influence of brain death on inflammatory response and the effects of brain death on liver function both directly after explantation and after reoxygenation. Methods: The influence of brain death on liver function was studied in rats using a brain death

  13. Robust transient dynamics and brain functions

    Directory of Open Access Journals (Sweden)

    Mikhail I Rabinovich

    2011-06-01

    Full Text Available In the last few decades several concepts of Dynamical Systems Theory (DST have guided psychologists, cognitive scientists, and neuroscientists to rethink about sensory motor behavior and embodied cognition. A critical step in the progress of DST application to the brain (supported by modern methods of brain imaging and multi-electrode recording techniques has been the transfer of its initial success in motor behavior to mental function, i.e., perception, emotion, and cognition. Open questions from research in genetics, ecology, brain sciences, etc. have changed DST itself and lead to the discovery of a new dynamical phenomenon, i.e., reproducible and robust transients that are at the same time sensitive to informational signals. The goal of this review is to describe a new mathematical framework -heteroclinic sequential dynamics- to understand self-organized activity in the brain that can explain certain aspects of robust itinerant behavior. Specifically, we discuss a hierarchy of coarse-grain models of mental dynamics in the form of kinetic equations of modes. These modes compete for resources at three levels: (i within the same modality, (ii among different modalities from the same family (like perception, and (iii among modalities from different families (like emotion and cognition. The analysis of the conditions for robustness, i.e., the structural stability of transient (sequential dynamics, give us the possibility to explain phenomena like the finite capacity of our sequential working memory -a vital cognitive function-, and to find specific dynamical signatures -different kinds of instabilities- of several brain functions and mental diseases.

  14. Neural connectivity during reward expectation dissociates psychopathic criminals from non-criminal individuals with high impulsive/antisocial psychopathic traits.

    Science.gov (United States)

    Geurts, Dirk E M; von Borries, Katinka; Volman, Inge; Bulten, Berend Hendrik; Cools, Roshan; Verkes, Robbert-Jan

    2016-08-01

    Criminal behaviour poses a big challenge for society. A thorough understanding of the neurobiological mechanisms underlying criminality could optimize its prevention and management. Specifically,elucidating the neural mechanisms underpinning reward expectation might be pivotal to understanding criminal behaviour. So far no study has assessed reward expectation and its mechanisms in a criminal sample. To fill this gap, we assessed reward expectation in incarcerated, psychopathic criminals. We compared this group to two groups of non-criminal individuals: one with high levels and another with low levels of impulsive/antisocial traits. Functional magnetic resonance imaging was used to quantify neural responses to reward expectancy. Psychophysiological interaction analyses were performed to examine differences in functional connectivity patterns of reward-related regions. The data suggest that overt criminality is characterized, not by abnormal reward expectation per se, but rather by enhanced communication between reward-related striatal regions and frontal brain regions. We establish that incarcerated psychopathic criminals can be dissociated from non-criminal individuals with comparable impulsive/antisocial personality tendencies based on the degree to which reward-related brain regions interact with brain regions that control behaviour. The present results help us understand why some people act according to their impulsive/antisocial personality while others are able to behave adaptively despite reward-related urges.

  15. Neurophysiology of Reward-Guided Behavior: Correlates Related to Predictions, Value, Motivation, Errors, Attention, and Action.

    Science.gov (United States)

    Bissonette, Gregory B; Roesch, Matthew R

    2016-01-01

    Many brain areas are activated by the possibility and receipt of reward. Are all of these brain areas reporting the same information about reward? Or are these signals related to other functions that accompany reward-guided learning and decision-making? Through carefully controlled behavioral studies, it has been shown that reward-related activity can represent reward expectations related to future outcomes, errors in those expectations, motivation, and signals related to goal- and habit-driven behaviors. These dissociations have been accomplished by manipulating the predictability of positively and negatively valued events. Here, we review single neuron recordings in behaving animals that have addressed this issue. We describe data showing that several brain areas, including orbitofrontal cortex, anterior cingulate, and basolateral amygdala signal reward prediction. In addition, anterior cingulate, basolateral amygdala, and dopamine neurons also signal errors in reward prediction, but in different ways. For these areas, we will describe how unexpected manipulations of positive and negative value can dissociate signed from unsigned reward prediction errors. All of these signals feed into striatum to modify signals that motivate behavior in ventral striatum and guide responding via associative encoding in dorsolateral striatum.

  16. Functional Recovery After Severe Traumatic Brain Injury

    DEFF Research Database (Denmark)

    Hart, Tessa; Kozlowski, Allan; Whyte, John

    2014-01-01

    OBJECTIVE: To examine person, injury, and treatment characteristics associated with recovery trajectories of people with severe traumatic brain injury (TBI) during inpatient rehabilitation. DESIGN: Observational prospective longitudinal study. SETTING: Two specialized inpatient TBI rehabilitation...... functional levels received more treatment and more treatment was associated with slower recovery, presumably because treatment was allocated according to need. Thus, effects of treatment on outcome could not be disentangled from effects of case mix factors. CONCLUSIONS: FIM gain during inpatient recovery...

  17. Cognitive functioning of the aging brain

    OpenAIRE

    Tam, Man-kin, Helena; 譚敏堅

    2013-01-01

    This thesis contains two studies which examined the cognitive functioning of the aging brain. Specifically, age-related changes in processing speed and its remediation via cognitive training were studied. In study 1, younger adults (n = 34) and older adults (n = 39) were recruited to investigate the age-related differences in the relationships between processing speed and general cognitive status (GCS). Their performance in GCS (as measured by The Montreal Cognitive Assessment, Hong Kong Vers...

  18. Social functioning in children with brain insult

    Directory of Open Access Journals (Sweden)

    Mardee Greenham

    2010-03-01

    Full Text Available Social dysfunction is commonly reported by survivors of brain insult, and is often rated as the most debilitating of all sequelae, impacting on many areas of daily life, as well as overall quality of life. Within the early brain insult (EBI literature, physical and cognitive domains have been of primary interest and social skills have received scant attention. As a result it remains unclear how common these problems are, and whether factors predictive of recovery (insult severity, lesion location, age at insult, environment in other functional domains (motor, speech, cognition also contribute to social outcome. This study compared social outcomes for children sustaining EBI at different times from gestation to late childhood to determine whether EBI was associated with an increased risk of problems. Children with focal brain insults were categorized according to timing of brain insult: (i Congenital (n = 38: EBI: first–second trimester; (ii Perinatal (n = 33; EBI: third trimester to 1 month post-natal; (iii Infancy (n=23: EBI: 2 months–2 years post-birth; (iv Preschool (n = 19: EBI: 3–6 years; (v Middle Childhood (n = 31: EBI: 7–9 years; and (vi Late Childhood (n = 19: EBI: after age 10. Children’s teachers completed questionnaires measuring social function (Strengths and Difficulties Questionnaire, Walker McConnell Scale of Social Competence and School Adjustment. Results showed that children with EBI were at increased risk for social impairment compared to normative expectations. EBI before age 2 years was associated with most significant social impairment, while children with EBI in the preschool years and in late childhood recorded scores closer to normal. Lesion location and laterality were not predictive of social outcome, and nor was social risk. In contrast, presence of disability (seizures and family function were shown to contribute to aspects of social function.

  19. When "altering brain function" becomes "mind control".

    Science.gov (United States)

    Koivuniemi, Andrew; Otto, Kevin

    2014-01-01

    Functional neurosurgery has seen a resurgence of interest in surgical treatments for psychiatric illness. Deep brain stimulation (DBS) technology is the preferred tool in the current wave of clinical experiments because it allows clinicians to directly alter the functions of targeted brain regions, in a reversible manner, with the intent of correcting diseases of the mind, such as depression, addiction, anorexia nervosa, dementia, and obsessive compulsive disorder. These promising treatments raise a critical philosophical and humanitarian question. "Under what conditions does 'altering brain function' qualify as 'mind control'?" In order to answer this question one needs a definition of mind control. To this end, we reviewed the relevant philosophical, ethical, and neurosurgical literature in order to create a set of criteria for what constitutes mind control in the context of DBS. We also outline clinical implications of these criteria. Finally, we demonstrate the relevance of the proposed criteria by focusing especially on serendipitous treatments involving DBS, i.e., cases in which an unintended therapeutic benefit occurred. These cases highlight the importance of gaining the consent of the subject for the new therapy in order to avoid committing an act of mind control.

  20. Functional brain networks in schizophrenia: a review

    Directory of Open Access Journals (Sweden)

    Vince D Calhoun

    2009-08-01

    Full Text Available Functional magnetic resonance imaging (fMRI has become a major technique for studying cognitive function and its disruption in mental illness, including schizophrenia. The major proportion of imaging studies focused primarily upon identifying regions which hemodynamic response amplitudes covary with particular stimuli and differentiate between patient and control groups. In addition to such amplitude based comparisons, one can estimate temporal correlations and compute maps of functional connectivity between regions which include the variance associated with event related responses as well as intrinsic fluctuations of hemodynamic activity. Functional connectivity maps can be computed by correlating all voxels with a seed region when a spatial prior is available. An alternative are multivariate decompositions such as independent component analysis (ICA which extract multiple components, each of which is a spatially distinct map of voxels with a common time course. Recent work has shown that these networks are pervasive in relaxed resting and during task performance and hence provide robust measures of intact and disturbed brain activity. This in turn bears the prospect of yielding biomarkers for schizophrenia, which can be described both in terms of disrupted local processing as well as altered global connectivity between large scale networks. In this review we will summarize functional connectivity measures with a focus upon work with ICA and discuss the meaning of intrinsic fluctuations. In addition, examples of how brain networks have been used for classification of disease will be shown. We present work with functional network connectivity, an approach that enables the evaluation of the interplay between multiple networks and how they are affected in disease. We conclude by discussing new variants of ICA for extracting maximally group discriminative networks from data. In summary, it is clear that identification of brain networks and their

  1. Non-invasive brain-to-brain interface (BBI: establishing functional links between two brains.

    Directory of Open Access Journals (Sweden)

    Seung-Schik Yoo

    Full Text Available Transcranial focused ultrasound (FUS is capable of modulating the neural activity of specific brain regions, with a potential role as a non-invasive computer-to-brain interface (CBI. In conjunction with the use of brain-to-computer interface (BCI techniques that translate brain function to generate computer commands, we investigated the feasibility of using the FUS-based CBI to non-invasively establish a functional link between the brains of different species (i.e. human and Sprague-Dawley rat, thus creating a brain-to-brain interface (BBI. The implementation was aimed to non-invasively translate the human volunteer's intention to stimulate a rat's brain motor area that is responsible for the tail movement. The volunteer initiated the intention by looking at a strobe light flicker on a computer display, and the degree of synchronization in the electroencephalographic steady-state-visual-evoked-potentials (SSVEP with respect to the strobe frequency was analyzed using a computer. Increased signal amplitude in the SSVEP, indicating the volunteer's intention, triggered the delivery of a burst-mode FUS (350 kHz ultrasound frequency, tone burst duration of 0.5 ms, pulse repetition frequency of 1 kHz, given for 300 msec duration to excite the motor area of an anesthetized rat transcranially. The successful excitation subsequently elicited the tail movement, which was detected by a motion sensor. The interface was achieved at 94.0±3.0% accuracy, with a time delay of 1.59±1.07 sec from the thought-initiation to the creation of the tail movement. Our results demonstrate the feasibility of a computer-mediated BBI that links central neural functions between two biological entities, which may confer unexplored opportunities in the study of neuroscience with potential implications for therapeutic applications.

  2. Associations between polygenic risk for schizophrenia and brain function during probabilistic learning in healthy individuals.

    Science.gov (United States)

    Lancaster, Thomas M; Ihssen, Niklas; Brindley, Lisa M; Tansey, Katherine E; Mantripragada, Kiran; O'Donovan, Michael C; Owen, Michael J; Linden, David E J

    2016-02-01

    A substantial proportion of schizophrenia liability can be explained by additive genetic factors. Risk profile scores (RPS) directly index risk using a summated total of common risk variants weighted by their effect. Previous studies suggest that schizophrenia RPS predict alterations to neural networks that support working memory and verbal fluency. In this study, we apply schizophrenia RPS to fMRI data to elucidate the effects of polygenic risk on functional brain networks during a probabilistic-learning neuroimaging paradigm. The neural networks recruited during this paradigm have previously been shown to be altered to unmedicated schizophrenia patients and relatives of schizophrenia patients, which may reflect genetic susceptibility. We created schizophrenia RPS using summary data from the Psychiatric Genetic Consortium (Schizophrenia Working Group) for 83 healthy individuals and explore associations between schizophrenia RPS and blood oxygen level dependency (BOLD) during periods of choice behavior (switch-stay) and reflection upon choice outcome (reward-punishment). We show that schizophrenia RPS is associated with alterations in the frontal pole (PWHOLE-BRAIN-CORRECTED  = 0.048) and the ventral striatum (PROI-CORRECTED  = 0.036), during choice behavior, but not choice outcome. We suggest that the common risk variants that increase susceptibility to schizophrenia can be associated with alterations in the neural circuitry that support the processing of changing reward contingencies. Hum Brain Mapp 37:491-500, 2016. © 2015 Wiley Periodicals, Inc.

  3. Adaptive Design of Role Differentiation by Division of Reward Function in Multi-Agent Reinforcement Learning

    Science.gov (United States)

    Taniguchi, Tadahiro; Tabuchi, Kazuma; Sawaragi, Tetsuo

    There are several problems which discourage an organization from achieving tasks, e.g., partial observation, credit assignment, and concurrent learning in multi-agent reinforcement learning. In many conventional approaches, each agent estimates hidden states, e.g., sensor inputs, positions, and policies of other agents, and reduces the uncertainty in the partially-observable Markov decision process (POMDP), which partially solve the multiagent reinforcement learning problem. In contrast, people reduce uncertainty in human organizations in the real world by autonomously dividing the roles played by individual agents. In a framework of reinforcement learning, roles are mainly represented by goals for individual agents. This paper presents a method for generating internal rewards from manager agents to worker agents. It also explicitly divides the roles, which enables a POMDP task for each agent to be transformed into a simple MDP task under certain conditions. Several situational experiments are also described and the validity of the proposed method is evaluated.

  4. The role of the dorsal raphé nucleus in reward-seeking behavior

    Directory of Open Access Journals (Sweden)

    Kae eNakamura

    2013-08-01

    Full Text Available Pharmacological experiments have shown that the modulation of brain serotonin levels has a strong impact on value-based decision making. Anatomical and physiological evidence also revealed that the dorsal raphé nucleus (DRN, a major source of serotonin, and the dopamine system receive common inputs from brain regions associated with appetitive and aversive information processing. The serotonin and dopamine systems also have reciprocal functional influences on each other. However, the specific mechanism by which serotonin affects value-based decision making is not clear.To understand the information carried by the DRN for reward-seeking behavior, we measured single neuron activity in the primate DRN during the performance of saccade tasks to obtain different amounts of a reward. We found that DRN neuronal activity was characterized by tonic modulation that was altered by the expected and received reward value. Consistent reward-dependent modulation across different task periods suggested that DRN activity kept track of the reward value throughout a trial. The DRN was also characterized by modulation of its activity in the opposite direction by different neuronal subgroups, one firing strongly for the prediction and receipt of large rewards, with the other firing strongly for small rewards. Conversely, putative dopamine neurons showed positive phasic responses to reward-indicating cues and the receipt of an unexpected reward amount, which supports the reward prediction error signal hypothesis of dopamine.I suggest that the tonic reward monitoring signal of the DRN, possibly together with its interaction with the dopamine system, reports a continuous level of motivation throughout the performance of a task. Such a signal may provide reward context information to the targets of DRN projections, where it may be integrated further with incoming motivationally salient information.

  5. Pavlovian conditioning to food reward as a function of eating disorder risk.

    Science.gov (United States)

    Astur, Robert S; Palmisano, Alexandra N; Hudd, Ellie C; Carew, Andrew W; Deaton, Bonnie E; Kuhney, Franchesca S; Niezrecki, Rachel N; Santos, Melissa

    2015-09-15

    The aim of this experiment was to examine the extent to which eating disorder risk affects the strength of food-reward conditioning. Eighty food-restricted undergraduates were placed into a VR environment consisting of two visually distinct rooms. Participants underwent multiple pairing sessions in which they were confined into one of the two rooms and explored a VR environment. Room A was paired with real-life M&Ms for three sessions, and Room B was paired with no food for three sessions. After a short delay, a test session was administered, and participants were given free access to the entire VR environment for 5 min. Participants also completed the Eating Attitudes Test (EAT-26; [11]), which is a standard screening tool of eating disorder risk. Participants displayed a significant conditioned place preference for the VR room previously paired with food, and they displayed a significant explicit preference for the M&M-paired room in a forced-choice test. There was a significant positive correlation between place preference strength and scores on the dieting subscale of the EAT-26. Additionally, ratings of the no-food room were significantly lower as dieting scores increased. This suggests that components of eating disorder risk can influence basic conditioning strength to places associated with food reward. For both males and females, additional correlations between eating disorder risk subscales and conditioning variables are discussed, and implications for future research are proposed in hopes of understanding how conditioning paradigms can provide insight into treating and preventing eating disorders.

  6. How do brain tumors alter functional connectivity? : A magnetoencephalography study

    NARCIS (Netherlands)

    Bartolomei, Fabrice; Bosma, Ingeborg; Klein, Martin; Baayen, Johannes C; Reijneveld, Jaap C; Postma, Tjeerd J; Heimans, Jan J; van Dijk, Bob W; de Munck, Jan C; de Jongh, Arent; Cover, Keith S; Stam, Cornelis J

    2006-01-01

    OBJECTIVE: This study was undertaken to test the hypothesis that brain tumors interfere with normal brain function by disrupting functional connectivity of brain networks. METHODS: Functional connectivity was assessed by computing the synchronization likelihood in a broad band (0.5-60Hz) or in the g

  7. The Big Five default brain: functional evidence.

    Science.gov (United States)

    Sampaio, Adriana; Soares, José Miguel; Coutinho, Joana; Sousa, Nuno; Gonçalves, Óscar F

    2014-11-01

    Recent neuroimaging studies have provided evidence that different dimensions of human personality may be associated with specific structural neuroanatomic correlates. Identifying brain correlates of a situation-independent personality structure would require evidence of a stable default mode of brain functioning. In this study, we investigated the correlates of the Big Five personality dimensions (Extraversion, Neuroticism, Openness/Intellect, Agreeableness, and Conscientiousness) and the default mode network (DMN). Forty-nine healthy adults completed the NEO-Five Factor. The results showed that the Extraversion (E) and Agreeableness (A) were positively correlated with activity in the midline core of the DMN, whereas Neuroticism (N), Openness (O), and Conscientiousness (C) were correlated with the parietal cortex system. Activity of the anterior cingulate cortex was positively associated with A and negatively with C. Regions of the parietal lobe were differentially associated with each personality dimension. The present study not only confirms previous functional correlates regarding the Big Five personality dimensions, but it also expands our knowledge showing the association between different personality dimensions and specific patterns of brain activation at rest.

  8. When Altering Brain Function Becomes Mind Control

    Directory of Open Access Journals (Sweden)

    Andrew Sanford Koivuniemi

    2014-10-01

    Full Text Available Functional neurosurgery has seen a resurgence of interest in surgical treatments for psychiatric illness. Deep brain stimulation (DBS technology is the preferred tool in the current wave of clinical experiments because it allows clinicians to directly alter the functions of targeted brain regions, in a reversible manner, with the intent of correcting diseases of the mind, such as depression, addiction, anorexia nervosa, dementia, and obsessive compulsive disorder. These promising treatments raise a critical philosophical and humanitarian question. Under what conditions does ‘altering brain function’ qualify as ‘mind control’? In order to answer this question one needs a definition of mind control. To this end, we reviewed the relevant philosophical, ethical, and neurosurgical literature in order to create a set of criteria for what constitutes mind control in the context of DBS. We also outline clinical implications of these criteria. Finally, we demonstrate the relevance of the proposed criteria by focusing especially on serendipitous treatments involving DBS, i.e., cases in which an unintended therapeutic benefit occurred. These cases highlight the importance of gaining the consent of the subject for the new therapy in order to avoid committing an act of mind control.

  9. Memory Consolidation and Neural Substrate of Reward

    Directory of Open Access Journals (Sweden)

    Redolar-Ripoll, Diego

    2012-08-01

    Full Text Available The aim of this report is to analyze the relationships between reward and learning and memory processes. Different studies have described how information about rewards influences behavior and how the brain uses this reward information to control learning and memory processes. Reward nature seems to be processed in different ways by neurons in different brain structures, ranging from the detection and perception of rewards to the use of information about predicted rewards for the control of goal-directed behavior. The neural substrate underling this processing of reward information is a reliable way of improving learning and memory processes. Evidence from several studies indicates that this neural system can facilitate memory consolidation in a wide variety of learning tasks. From a molecular perspective, certain cardinal features of reward have been described as forms of memory. Studies of human addicts and studies in animal models of addiction show that chronic drug exposure produces stable changes in the brain at the cellular and molecular levels that underlie the long-lasting behavioral plasticity associated with addiction. These molecular and cellular adaptations involved in addiction are also implicated in learning and memory processes. Dopamine seems to be a critical common signal to activate different genetic mechanisms that ultimately remodel synapses and circuits. Despite memory is an active and complex process mediated by different brain areas, the neural substrate of reward is able to improve memory consolidation in a several paradigms. We believe that there are many equivalent traits between reward and learning and memory processes.

  10. Unravelling the differential functions and regulation of striatal neuron sub-populations in motor control, reward and motivational processes

    Directory of Open Access Journals (Sweden)

    Sabrina eEna

    2011-07-01

    Full Text Available The striatum, the major input structure of the basal ganglia, is critically involved in motor control and learning of habits and skills, and is also involved in motivational and reward processes. The dorsal striatum, caudate-putamen, is primarily implicated in motor functions whereas the ventral striatum, the nucleus accumbens, is essential for motivation and drug reinforcement. Severe basal ganglia dysfunction occurs in movement disorders as Parkinson’s and Huntington’s disease, and in psychiatric disorders such as schizophrenia and drug addiction. The striatum is essentially composed of GABAergic medium-sized spiny neurons (MSNs that are output neurons giving rise to the so-called direct and indirect pathways and are targets of the cerebral cortex and mesencephalic dopaminergic neurons. Although the involvement of striatal sub-areas in motor control and motivation has been thoroughly characterized, major issues remained concerning the specific and respective functions of the two MSNs sub-populations, D2R-striatopallidal (dopamine D2 receptor-positive and D1R-striatonigral (dopamine D1 receptor-positive neurons, as well as their specific regulation. Here, we review recent advances that gave new insight in the understanding of the differential roles of striatopallidal and striatonigral neurons in the basal ganglia circuit. We discuss innovative techniques developed in the last decade which allowed a much precise evaluation of molecular pathways implicated in motivational processes and functional roles of striatopallidal and striatonigral neurons in motor control and in the establishment of reward-associated behaviour.

  11. Oxytocin selectively facilitates learning with social feedback and increases activity and functional connectivity in emotional memory and reward processing regions.

    Science.gov (United States)

    Hu, Jiehui; Qi, Song; Becker, Benjamin; Luo, Lizhu; Gao, Shan; Gong, Qiyong; Hurlemann, René; Kendrick, Keith M

    2015-06-01

    In male Caucasian subjects, learning is facilitated by receipt of social compared with non-social feedback, and the neuropeptide oxytocin (OXT) facilitates this effect. In this study, we have first shown a cultural difference in that male Chinese subjects actually perform significantly worse in the same reinforcement associated learning task with social (emotional faces) compared with non-social feedback. Nevertheless, in two independent double-blind placebo (PLC) controlled between-subject design experiments we found OXT still selectively facilitated learning with social feedback. Similar to Caucasian subjects this OXT effect was strongest with feedback using female rather than male faces. One experiment performed in conjunction with functional magnetic resonance imaging showed that during the response, but not feedback phase of the task, OXT selectively increased activity in the amygdala, hippocampus, parahippocampal gyrus and putamen during the social feedback condition, and functional connectivity between the amygdala and insula and caudate. Therefore, OXT may be increasing the salience and reward value of anticipated social feedback. In the PLC group, response times and state anxiety scores during social feedback were associated with signal changes in these same regions but not in the OXT group. OXT may therefore have also facilitated learning by reducing anxiety in the social feedback condition. Overall our results provide the first evidence for cultural differences in social facilitation of learning per se, but a similar selective enhancement of learning with social feedback under OXT. This effect of OXT may be associated with enhanced responses and functional connectivity in emotional memory and reward processing regions.

  12. Neural correlates of reward processing in healthy siblings of patients with schizophrenia.

    Science.gov (United States)

    Hanssen, Esther; van der Velde, Jorien; Gromann, Paula M; Shergill, Sukhi S; de Haan, Lieuwe; Bruggeman, Richard; Krabbendam, Lydia; Aleman, André; van Atteveldt, Nienke

    2015-01-01

    Deficits in motivational behavior and psychotic symptoms often observed in schizophrenia (SZ) may be driven by dysfunctional reward processing (RP). RP can be divided in two different stages; reward anticipation and reward consumption. Aberrant processing during reward anticipation seems to be related to SZ. Studies in patients with SZ have found less activation in the ventral striatum (VS) during anticipation of reward, but these findings do not provide information on effect of the genetic load on reward processing. Therefore, this study investigated RP in healthy first-degree relatives of SZ patients. The sample consisted of 94 healthy siblings of SZ patients and 57 healthy controls. Participants completed a classic RP task, the Monetary Incentive Delay task, during functional magnetic resonance imaging (fMRI). As expected, there were no behavioral differences between groups. In contrast to our expectations, we found no differences in any of the anticipatory reward related brain areas (region of interest analyses). Whole-brain analyses did reveal group differences during both reward anticipation and reward consumption; during reward anticipation siblings showed less deactivation in the insula, posterior cingulate cortex (PCC) and medial frontal gyrus (MFG) than controls. During reward consumption siblings showed less deactivation in the PCC and the right MFG compared to controls and activation in contrast to deactivation in controls in the precuneus and the left MFG. Exclusively in siblings, MFG activity correlated positively with subclinical negative symptoms. These regions are typically associated with the default mode network (DMN), which normally shows decreases in activation during task-related cognitive processes. Thus, in contrast to prior literature in patients with SZ, the results do not point to altered brain activity in classical RP brain areas, such as the VS. However, the weaker deactivation found outside the reward-related network in siblings could

  13. Structure and function of large-scale brain systems.

    Science.gov (United States)

    Koziol, Leonard F; Barker, Lauren A; Joyce, Arthur W; Hrin, Skip

    2014-01-01

    This article introduces the functional neuroanatomy of large-scale brain systems. Both the structure and functions of these brain networks are presented. All human behavior is the result of interactions within and between these brain systems. This system of brain function completely changes our understanding of how cognition and behavior are organized within the brain, replacing the traditional lesion model. Understanding behavior within the context of brain network interactions has profound implications for modifying abstract constructs such as attention, learning, and memory. These constructs also must be understood within the framework of a paradigm shift, which emphasizes ongoing interactions within a dynamically changing environment.

  14. Fast optical imaging of human brain function

    Directory of Open Access Journals (Sweden)

    Gabriele Gratton

    2010-06-01

    Full Text Available Great advancements in brain imaging during the last few decades have opened a large number of new possibilities for neuroscientists. The most dominant methodologies (electrophysiological and magnetic resonance-based methods emphasize temporal and spatial information, respectively. However, theorizing about brain function has recently emphasized the importance of rapid (within 100 ms or so interactions between different elements of complex neuronal networks. Fast optical imaging, and in particular the event-related optical signal (EROS, a technology that has emerged over the last 15 years may provide descriptions of localized (to sub-cm level brain activity with a temporal resolution of less than 100 ms. The main limitations of EROS are its limited penetration, which allows us to image cortical structures not deeper than 3 cm from the surface of the head, and its low signal-to-noise ratio. Advantages include the fact that EROS is compatible with most other imaging methods, including electrophysiological, magnetic resonance, and trans-cranial magnetic stimulation techniques, with which can be recorded concurrently. In this paper we present a summary of the research that has been conducted so far on fast optical imaging, including evidence for the possibility of recording neuronal signals with this method, the properties of the signals, and various examples of applications to the study of human cognitive neuroscience. Extant issues, controversies, and possible future developments are also discussed.

  15. On the physiology of jouissance: interpreting the mesolimbic dopaminergic reward functions from a psychoanalytic perspective

    Science.gov (United States)

    Bazan, Ariane; Detandt, Sandrine

    2013-01-01

    Jouissance is a Lacanian concept, infamous for being impervious to understanding and which expresses the paradoxical satisfaction that a subject may derive from his symptom. On the basis of Freud’s “experience of satisfaction” we have proposed a first working definition of jouissance as the (benefit gained from) the motor tension underlying the action which was [once] adequate in bringing relief to the drive and, on the basis of their striking reciprocal resonances, we have proposed that central dopaminergic systems could embody the physiological architecture of Freud’s concept of the drive. We have then distinguished two constitutive axes to jouissance: one concerns the subject’s body and the other the subject’s history. Four distinctive aspects of these axes are discussed both from a metapsychological and from a neuroscience point of view. We conclude that jouissance could be described as an accumulation of body tension, fuelling for action, but continuously balancing between reward and anxiety, and both marking the physiology of the body with the history of its commemoration and arising from this inscription as a constant push to act and to repeat. Moreover, it seems that the mesolimbic accumbens dopaminergic pathway is a reasonable candidate for its underlying physiological architecture. PMID:24223543

  16. Looking for reward in all the wrong places: dopamine receptor gene polymorphisms indirectly affect aggression through sensation-seeking.

    Science.gov (United States)

    Chester, David S; DeWall, C Nathan; Derefinko, Karen J; Estus, Steven; Lynam, Donald R; Peters, Jessica R; Jiang, Yang

    2016-10-01

    Individuals with genotypes that code for reduced dopaminergic brain activity often exhibit a predisposition toward aggression. However, it remains largely unknown how dopaminergic genotypes may increase aggression. Lower-functioning dopamine systems motivate individuals to seek reward from external sources such as illicit drugs and other risky experiences. Based on emerging evidence that aggression is a rewarding experience, we predicted that the effect of lower-functioning dopaminergic functioning on aggression would be mediated by tendencies to seek the environment for rewards. Caucasian female and male undergraduates (N = 277) were genotyped for five polymorphisms of the dopamine D2 receptor (DRD2) gene; they reported their previous history of aggression and their dispositional reward-seeking. Lower-functioning DRD2 profiles were associated with greater sensation-seeking, which then predicted greater aggression. Our findings suggest that lower-functioning dopaminergic activity puts individuals at risk for violence because it motivates them to experience aggression's hedonically rewarding qualities.

  17. Addiction is a reward deficit and stress surfeit disorder

    Directory of Open Access Journals (Sweden)

    George F Koob

    2013-08-01

    Full Text Available Drug addiction can be defined by a three-stage cycle—binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation—that involves allostatic changes in the brain reward and stress systems. Two primary sources of reinforcement, positive and negative reinforcement, have been hypothesized to play a role in this allostatic process. The negative emotional state that drives negative reinforcement is hypothesized to derive from dysregulation of key neurochemical elements involved in the brain reward and stress systems. Specific neurochemical elements in these structures include not only decreases in reward system function (within-system opponent processes but also recruitment of the brain stress systems mediated by corticotropin-releasing factor (CRF and dynorphin-κ opioid systems in the ventral striatum, extended amygdala, and frontal cortex (both between-system opponent processes. CRF antagonists block anxiety-like responses associated with withdrawal, block increases in reward thresholds produced by withdrawal from drugs of abuse, and block compulsive-like drug taking during extended access. Excessive drug taking also engages the activation of CRF in the medial prefrontal cortex, paralleled by deficits in executive function that may facilitate the transition to compulsive-like responding. Neuropeptide Y, a powerful anti-stress neurotransmitter, has a profile of action on compulsive-like responding for ethanol similar to a CRF1 antagonist. Blockade of the κ opioid system can also block dysphoric-like effects associated with withdrawal from drugs of abuse and block the development of compulsive-like responding during extended access to drugs of abuse, suggesting another powerful brain stress system that contributes to compulsive drug seeking. The loss of reward function and recruitment of brain systems provide a powerful neurochemical basis that drives the compulsivity of addiction.

  18. Abnormal Social Reward Responses in Anorexia Nervosa: An fMRI Study.

    Directory of Open Access Journals (Sweden)

    Esther Via

    Full Text Available Patients with anorexia nervosa (AN display impaired social interactions, implicated in the development and prognosis of the disorder. Importantly, social behavior is modulated by reward-based processes, and dysfunctional at-brain-level reward responses have been involved in AN neurobiological models. However, no prior evidence exists of whether these neural alterations would be equally present in social contexts. In this study, we conducted a cross-sectional social-judgment functional magnetic resonance imaging (fMRI study of 20 restrictive-subtype AN patients and 20 matched healthy controls. Brain activity during acceptance and rejection was investigated and correlated with severity measures (Eating Disorder Inventory -EDI-2 and with personality traits of interest known to modulate social behavior (The Sensitivity to Punishment and Sensitivity to Reward Questionnaire. Patients showed hypoactivation of the dorsomedial prefrontal cortex (DMPFC during social acceptance and hyperactivation of visual areas during social rejection. Ventral striatum activation during rejection was positively correlated in patients with clinical severity scores. During acceptance, activation of the frontal opercula-anterior insula and dorsomedial/dorsolateral prefrontal cortices was differentially associated with reward sensitivity between groups. These results suggest an abnormal motivational drive for social stimuli, and involve overlapping social cognition and reward systems leading to a disruption of adaptive responses in the processing of social reward. The specific association of reward-related regions with clinical and psychometric measures suggests the putative involvement of reward structures in the maintenance of pathological behaviors in AN.

  19. Neural signature of food reward processing in bulimic-type eating disorders.

    Science.gov (United States)

    Simon, Joe J; Skunde, Mandy; Walther, Stephan; Bendszus, Martin; Herzog, Wolfgang; Friederich, Hans-Christoph

    2016-09-01

    Clinical observations and similarities to addiction suggest heightened reward sensitivity to food in patients with bulimic-type eating (BTE) disorders. Therefore, we investigated the expectation and receipt of food reward compared with monetary reward in patients with BTE. Fifty-six patients with BTE (27 patients with binge eating disorder and 29 with bulimia nervosa) and 55 matched healthy control participants underwent event-related functional magnetic resonance imaging while performing both food and monetary incentive delay tasks. BTE patients exhibited reduced brain activation in the posterior cingulate cortex during the expectation of food and increased activity in the medial orbitofrontal cortex, anterior medial prefrontal cortex and posterior cingulate cortex during the receipt of food reward. These findings were relevant to food because we found no significant group differences related to monetary reward. In the patients, higher brain activity in the medial orbitofrontal cortex during the receipt of food reward was related to higher levels of trait food craving and external eating. BTE patients exhibited increased hedonic processing during the receipt of food reward. These findings corroborate the notion that an altered responsiveness of the reward network to food stimuli is associated with BTE.

  20. Self-affirmation activates brain systems associated with self-related processing and reward and is reinforced by future orientation.

    Science.gov (United States)

    Cascio, Christopher N; O'Donnell, Matthew Brook; Tinney, Francis J; Lieberman, Matthew D; Taylor, Shelley E; Strecher, Victor J; Falk, Emily B

    2016-04-01

    Self-affirmation theory posits that people are motivated to maintain a positive self-view and that threats to perceived self-competence are met with resistance. When threatened, self-affirmations can restore self-competence by allowing individuals to reflect on sources of self-worth, such as core values. Many questions exist, however, about the underlying mechanisms associated with self-affirmation. We examined the neural mechanisms of self-affirmation with a task developed for use in a functional magnetic resonance imaging environment. Results of a region of interest analysis demonstrated that participants who were affirmed (compared with unaffirmed participants) showed increased activity in key regions of the brain's self-processing (medial prefrontal cortex + posterior cingulate cortex) and valuation (ventral striatum + ventral medial prefrontal cortex) systems when reflecting on future-oriented core values (compared with everyday activities). Furthermore, this neural activity went on to predict changes in sedentary behavior consistent with successful affirmation in response to a separate physical activity intervention. These results highlight neural processes associated with successful self-affirmation, and further suggest that key pathways may be amplified in conjunction with prospection.

  1. Electroacupuncture decreases excessive alcohol consumption involving reduction of FosB/ΔFosB levels in reward-related brain regions.

    Directory of Open Access Journals (Sweden)

    Jing Li

    Full Text Available New therapies are needed for alcohol abuse, a major public health problem in the U.S. and worldwide. There are only three FDA-approved drugs for treatment of alcohol abuse (naltrexone, acamprosate and disulfuram. On average these drugs yield only moderate success in reducing long-term alcohol consumption. Electroacupuncture has been shown to alleviate various drugs of abuse, including alcohol. Although previous studies have shown that electroacupuncture reduced alcohol consumption, the underlying mechanisms have not been fully elucidated. ΔFosB and FosB are members of the Fos family of transcription factors implicated in neural plasticity in drug addiction; a connection between electroacupuncture's treatment of alcohol abuse and the Fos family has not been established. In this study, we trained rats to drink large quantities of ethanol in a modified intermittent access two-bottle choice drinking procedure. When rats achieved a stable baseline of ethanol consumption, electroacupuncture (100 Hz or 2 Hz, 30 min each day was administered at Zusanli (ST36 for 6 consecutive days. The level of FosB/ΔFosB in reward-related brain regions was assessed by immunohistochemistry. We found that the intake of and preference for ethanol in rats under 100 Hz, but not 2 Hz electroacupuncture regiment were sharply reduced. The reduction was maintained for at least 72 hours after the termination of electroacupuncture treatment. Conversely, 100 Hz electroacupuncture did not alter the intake of and preference for the natural rewarding agent sucrose. Additionally, FosB/ΔFosB levels in the prefrontal cortex, striatal region and the posterior region of ventral tegmental area were increased following excessive ethanol consumption, but were reduced after six-day 100 Hz electroacupuncture. Thus, this study demonstrates that six-day 100 Hz electroacupuncture treatment effectively reduces ethanol consumption and preference in rats that chronically drink excessive amount of

  2. Is the self a higher-order or fundamental function of the brain? The "basis model of self-specificity" and its encoding by the brain's spontaneous activity.

    Science.gov (United States)

    Northoff, Georg

    2016-01-01

    What is the self? This is a question that has long been discussed in (Western) philosophy where the self is traditionally conceived a higher-order function at the apex or pinnacle of all functions. This tradition has been transferred to recent neuroscience where the self is often considered to be a higher-order cognitive function reflected in memory and other high-level judgements. However, other lines of research demonstrate a close and intimate relationship between self-specificity and more basic functions like perceptions, emotions and reward. This paper focuses on the relationship between self-specificity and other basic functions relating to emotions, reward and perception. I propose the basis model that conceives self-specificity as a fundamental feature of the brain's spontaneous activity. This is supported by recent findings showing rest-self overlap in midline regions as well as findings demonstrating that the resting state can predict subsequent degrees of self-specificity. I conclude that such self-specificity in the brain's spontaneous activity may be central in linking the self to either internal or external stimuli. This may also provide the basis for coding the self as subject in relation to internal (i.e., self-consciousness) or external (i.e., phenomenal consciousness) mental events.

  3. Involvement of μ- and δ-opioid receptor function in the rewarding effect of (±)-pentazocine.

    Science.gov (United States)

    Mori, Tomohisa; Itoh, Toshimasa; Yoshizawa, Kazumi; Ise, Yuya; Mizuo, Keisuke; Saeki, Tomoya; Komiya, Sachiko; Masukawa, Daiki; Shibasaki, Masahiro; Suzuki, Tsutomu

    2015-07-01

    Most opioid receptor agonists have abuse potential, and the rewarding effects of opioids can be reduced in the presence of pain. While each of the enantiomers of pentazocine has a differential pharmacologic profile, (±)-pentazocine has been used clinically for the treatment of pain. However, little information is available regarding which components of pentazocine are associated with its rewarding effects, and whether the (±)-pentazocine-induced rewarding effects can be suppressed under pain. Therefore, the present study was performed to investigate the effects of pain on the acquisition of the rewarding effects of (±)-pentazocine, and to examine the mechanism of the rewarding effects of (±)-pentazocine using the conditioned place preference paradigm. (±)-Pentazocine and (-)-pentazocine, but not (+)-pentazocine, produced significant rewarding effects. Even though the rewarding effects induced by (±)-pentazocine were significantly suppressed under pain induced by formalin, accompanied by increase of preprodynorphin mRNA levels in the nucleus accumbens, a high dose of (±)-pentazocine produced significant rewarding effects under pain. In the normal condition, (±)-pentazocine-induced rewarding effects were blocked by a low dose of naloxone, whereas the rewarding effects induced by high doses of pentazocine under pain were suppressed by naltrindole (a δ-opioid receptor antagonist). Interestingly, (±)-pentazocine did not significantly affect dopamine levels in the nucleus accumbens. These findings suggest that the rewarding effects of (-)-pentazocine may contribute to the abuse potential of (±)-pentazocine through μ- as well as δ-opioid receptors, without robust activation of the mesolimbic dopaminergic system. We also found that neural adaptations can reduce the abuse potential of (±)-pentazocine under pain.

  4. Functional Reorganizations of Brain Network in Prelingually Deaf Adolescents

    OpenAIRE

    Wenjing Li; Jianhong Li; Jieqiong Wang; Peng Zhou; Zhenchang Wang; Junfang Xian; Huiguang He

    2016-01-01

    Previous neuroimaging studies suggested structural or functional brain reorganizations occurred in prelingually deaf subjects. However, little is known about the reorganizations of brain network architectures in prelingually deaf adolescents. The present study aims to investigate alterations of whole-brain functional network using resting-state fMRI and graph theory analysis. We recruited 16 prelingually deaf adolescents (10~18 years) and 16 normal controls matched in age and gender. Brain ne...

  5. Reward and learning in the goldfish.

    Science.gov (United States)

    Lowes, G; Bitterman, M E

    1967-07-28

    An experiment with goldfish showed the effects of change in amount of reward that are predicted from reinforcement theory. The performance of animals shifted from small to large reward improved gradually to the level of unshifted large-reward controls, while the performance of animals shifted from large to small reward remained at the large-reward level. The difference between these results and those obtained in analogous experiments with the rat suggests that reward functions differently in the instrumental learning of the two animals.

  6. An Upside to Reward Sensitivity: The Hippocampus Supports Enhanced Reinforcement Learning in Adolescence.

    Science.gov (United States)

    Davidow, Juliet Y; Foerde, Karin; Galván, Adriana; Shohamy, Daphna

    2016-10-05

    Adolescents are notorious for engaging in reward-seeking behaviors, a tendency attributed to heightened activity in the brain's reward systems during adolescence. It has been suggested that reward sensitivity in adolescence might be adaptive, but evidence of an adaptive role has been scarce. Using a probabilistic reinforcement learning task combined with reinforcement learning models and fMRI, we found that adolescents showed better reinforcement learning and a stronger link between reinforcement learning and episodic memory for rewarding outcomes. This behavioral benefit was related to heightened prediction error-related BOLD activity in the hippocampus and to stronger functional connectivity between the hippocampus and the striatum at the time of reinforcement. These findings reveal an important role for the hippocampus in reinforcement learning in adolescence and suggest that reward sensitivity in adolescence is related to adaptive differences in how adolescents learn from experience.

  7. Developmental effects of reward on sustained attention networks.

    Science.gov (United States)

    Smith, Anna B; Halari, Rozmin; Giampetro, Vincent; Brammer, Michael; Rubia, Katya

    2011-06-01

    Adolescence is typified by significant maturation in higher-level attention functions coupled with less developed control over motivation, and enhanced sensitivity to novelty and reward. This study used event-related functional magnetic resonance imaging (fMRI) in seventy male and female participants aged between 10 and 43 years to identify age-related linear changes in cognitive sustained attention systems and the impact of reward on these systems, using a sustained attention task with and without a rewarded condition. For the non-rewarded sustained attention contrast, increasing age was associated with activation increases in typical regions of sustained attention including right inferior frontal, superior temporo-parietal and cerebellar cortices. Age-related activation decreases were observed within more posterior regions including posterior cingulate, insula and posterior cerebellar cortices, presumably mediating visual-spatial saliency detection. The effect of reward on sustained attention networks was associated with increased activation with age in regions associated with both executive attention control and reward processing, including dorsolateral, inferior and ventromedial prefrontal cortices (PFC), striatum, and temporo-parietal regions, suggestive of greater integration and executive control of motivation and cognition with maturity. Activation in paralimbic posterior cingulate and inferior temporal brain regions of visual-spatial saliency processing was progressively reduced in activation with increasing development. Thus, with increasing development between adolescence and adulthood, reward appears to enhance maturing cognitive sustained attention and executive reward-processing networks, whilst reducing paralimbic regions of saliency detection. These findings may be the neural underpinnings for the progressive maturation of motivational control over risk taking behaviours between adolescence and adulthood.

  8. The anabolic steroid nandrolone alters cannabinoid self-administration and brain CB1 receptor density and function.

    Science.gov (United States)

    Struik, Dicky; Fadda, Paola; Zara, Tamara; Zamberletti, Erica; Rubino, Tiziana; Parolaro, Daniela; Fratta, Walter; Fattore, Liana

    2017-01-01

    Clinical and pre-clinical observations indicate that anabolic-androgenic steroids can induce neurobiological changes that alter the rewarding effects of drugs of abuse. In this study, we investigated the effect of the anabolic steroid nandrolone on the rewarding properties of the cannabinoid CB1 receptor agonist WIN55,212-2 (WIN) in rats. Lister Hooded male rats were treated intramuscularly with nandrolone (15mg/kg) or vehicle for 14 consecutive days, and then allowed to self-administer WIN (12.5μg/kg/infusion) intravenously. After reaching stable drug intake, self-administration behavior was extinguished to examine drug- and cue-induced reinstatement of cannabinoid-seeking behavior. Other behavioral parameters presumed to influence drug-taking and drug-seeking behaviors were examined to gain more insight into the behavioral specificity of nandrolone treatment. Finally, animals were sacrificed for analysis of CB1 receptor density and function in selected brain areas. We found that nandrolone-treated rats self-administered up to 2 times more cannabinoid than vehicle-treated rats, but behaved similarly to control rats when tested for drug- and cue-induced reinstatement of cannabinoid-seeking behavior. Enhanced cannabinoid intake by nandrolone-treated rats was not accompanied by changes in locomotor activity, sensorimotor gating, or memory function. However, our molecular data show that after chronic WIN self-administration nandrolone-treated rats display altered CB1 receptor density and function in selected brain areas. We hypothesize that increased cannabinoid self-administration in nandrolone-treated rats results from a nandrolone-induced decrease in reward function, which rats seem to compensate by voluntarily increasing their cannabinoid intake. Altogether, our findings corroborate the hypothesis that chronic exposure to anabolic-androgenic steroids induces dysfunction of the reward pathway in rats and might represent a potential risk factor for abuse of

  9. Love-related changes in the brain: A resting-state functional magnetic resonance imaging study

    Directory of Open Access Journals (Sweden)

    Hongwen eSong

    2015-02-01

    Full Text Available Romantic love is a motivational state associated with a desire to enter or maintain a close relationship with a specific other person. Studies with functional magnetic resonance imaging (fMRI have found activation increases in brain regions involved in processing of reward, emotion, motivation when romantic lovers view photographs of their partners. However, not much is known on whether romantic love affects the brain’s functional architecture during rest. In the present study, resting state functional magnetic resonance imaging (rsfMRI data was collected to compare the regional homogeneity (ReHo and functional connectivity (FC across a lover group (LG, N=34, currently intensely in love, ended-love group (ELG, N=34, romantic relationship ended recently, and single group (SG, N=32, never fallen in love.The results showed that:1 ReHo of the left dorsal anterior cingulate cortex (dACC was significantly increased in the LG (in comparison to the ELG and the SG; 2 ReHo of the left dACC was positively correlated with length of time in love in the LG, and negatively correlated with the lovelorn duration since breakup in the ELG; 3 functional connectivity (FC within the reward, motivation, and emotion network (dACC, insula, caudate, amygdala and nucleus accumbens and the social cognition network (temporo-parietal junction (TPJ, posterior cingulate cortex (PCC, medial prefrontal cortex (MPFC, inferior parietal, precuneus and temporal lobe was significantly increased in the LG (in comparison to the ELG and SG; 4 in most regions within both networks FC was positively correlated with the love duration in the LG but negatively correlated with the lovelorn duration in the ELG. This study provides first empirical evidence of love-related alterations of brain functional architecture. The results shed light on the underlying neural mechanisms of romantic love, and demonstrate the possibility of applying a resting state approach for investigating romantic love.

  10. Default mode of brain function in monkeys.

    Science.gov (United States)

    Mantini, Dante; Gerits, Annelis; Nelissen, Koen; Durand, Jean-Baptiste; Joly, Olivier; Simone, Luciano; Sawamura, Hiromasa; Wardak, Claire; Orban, Guy A; Buckner, Randy L; Vanduffel, Wim

    2011-09-07

    Human neuroimaging has revealed a specific network of brain regions-the default-mode network (DMN)-that reduces its activity during goal-directed behavior. So far, evidence for a similar network in monkeys is mainly indirect, since, except for one positron emission tomography study, it is all based on functional connectivity analysis rather than activity increases during passive task states. Here, we tested whether a consistent DMN exists in monkeys using its defining property. We performed a meta-analysis of functional magnetic resonance imaging data collected in 10 awake monkeys to reveal areas in which activity consistently decreases when task demands shift from passive tasks to externally oriented processing. We observed task-related spatially specific deactivations across 15 experiments, implying in the monkey a functional equivalent of the human DMN. We revealed by resting-state connectivity that prefrontal and medial parietal regions, including areas 9/46d and 31, respectively, constitute the DMN core, being functionally connected to all other DMN areas. We also detected two distinct subsystems composed of DMN areas with stronger functional connections between each other. These clusters included areas 24/32, 8b, and TPOC and areas 23, v23, and PGm, respectively. Such a pattern of functional connectivity largely fits, but is not completely consistent with anatomical tract tracing data in monkeys. Also, analysis of afferent and efferent connections between DMN areas suggests a multisynaptic network structure. Like humans, monkeys increase activity during passive epochs in heteromodal and limbic association regions, suggesting that they also default to internal modes of processing when not actively interacting with the environment.

  11. Fronto-striatal dysfunction during reward processing in unaffected siblings of schizophrenia patients.

    Science.gov (United States)

    de Leeuw, Max; Kahn, René S; Vink, Matthijs

    2015-01-01

    Schizophrenia is a psychiatric disorder that is associated with impaired functioning of the fronto-striatal network, in particular during reward processing. However, it is unclear whether this dysfunction is related to the illness itself or whether it reflects a genetic vulnerability to develop schizophrenia. Here, we examined reward processing in unaffected siblings of schizophrenia patients using functional magnetic resonance imaging. Brain activity was measured during reward anticipation and reward outcome in 27 unaffected siblings of schizophrenia patients and 29 healthy volunteers using a modified monetary incentive delay task. Task performance was manipulated online so that all subjects won the same amount of money. Despite equal performance, siblings showed reduced activation in the ventral striatum, insula, and supplementary motor area (SMA) during reward anticipation compared to controls. Decreased ventral striatal activation in siblings was correlated with sub-clinical negative symptoms. During the outcome of reward, siblings showed increased activation in the ventral striatum and orbitofrontal cortex compared to controls. Our finding of decreased activity in the ventral striatum during reward anticipation and increased activity in this region during receiving reward may indicate impaired cue processing in siblings. This is consistent with the notion of dopamine dysfunction typically associated with schizophrenia. Since unaffected siblings share on average 50% of their genes with their ill relatives, these deficits may be related to the genetic vulnerability for schizophrenia.

  12. Hierarchical Functional Modularity in the Resting-State Human Brain

    NARCIS (Netherlands)

    Ferrarini, Luca; Veer, Ilya M.; Baerends, Evelinda; van Tol, Marie-Jose; Renken, Remco J.; van der Wee, Nic J. A.; Veltman, Dirk. J.; Aleman, Andre; Zitman, Frans G.; Penninx, Brenda W. J. H.; van Buchem, Mark A.; Reiber, Johan H. C.; Rombouts, Serge A. R. B.; Milles, Julien

    2009-01-01

    Functional magnetic resonance imaging (fMRI) studies have shown that anatomically distinct brain regions are functionally connected during the resting state. Basic topological properties in the brain functional connectivity (BFC) map have highlighted the BFC's small-world topology. Modularity, a mor

  13. The physiological and biochemical bases of functional brain imaging

    OpenAIRE

    2007-01-01

    Functional brain imaging is based on the display of computer-derived images of changes in physiological and/or biochemical functions altered by activation or depression of local functional activities in the brain. This article reviews the physiological and biochemical mechanisms involved.

  14. Mapping distributed brain function and networks with diffuse optical tomography

    Science.gov (United States)

    Eggebrecht, Adam T.; Ferradal, Silvina L.; Robichaux-Viehoever, Amy; Hassanpour, Mahlega S.; Dehghani, Hamid; Snyder, Abraham Z.; Hershey, Tamara; Culver, Joseph P.

    2014-06-01

    Mapping of human brain function has revolutionized systems neuroscience. However, traditional functional neuroimaging by positron emission tomography or functional magnetic resonance imaging cannot be used when applications require portability, or are contraindicated because of ionizing radiation (positron emission tomography) or implanted metal (functional magnetic resonance imaging). Optical neuroimaging offers a non-invasive alternative that is radiation free and compatible with implanted metal and electronic devices (for example, pacemakers). However, optical imaging technology has heretofore lacked the combination of spatial resolution and wide field of view sufficient to map distributed brain functions. Here, we present a high-density diffuse optical tomography imaging array that can map higher-order, distributed brain function. The system was tested by imaging four hierarchical language tasks and multiple resting-state networks including the dorsal attention and default mode networks. Finally, we imaged brain function in patients with Parkinson's disease and implanted deep brain stimulators that preclude functional magnetic resonance imaging.

  15. Endocannabinoid signaling in reward and addiction

    OpenAIRE

    Parsons, Loren H.; Hurd, Yasmin L.

    2015-01-01

    Brain endocannabinoid signaling influences the motivation for natural rewards (such as palatable food, sexual activity and social interaction) and modulates the rewarding effects of addictive drugs. Pathological forms of natural and drug-induced reward are associated with dysregulated endocannabinoid signaling that may derive from pre-existing genetic factors or from prolonged drug exposure. Impaired endocannabinoid signaling contributes to dysregulated synaptic plasticity, increased stress r...

  16. Changes in cognitive state alter human functional brain networks

    Directory of Open Access Journals (Sweden)

    Malaak Nasser Moussa

    2011-08-01

    Full Text Available The study of the brain as a whole system can be accomplished using network theory principles. Research has shown that human functional brain networks during a resting state exhibit small-world properties and high degree nodes, or hubs, localized to brain areas consistent with the default mode network (DMN. However, the study of brain networks across different tasks and or cognitive states has been inconclusive. Research in this field is important because the underpinnings of behavioral output are inherently dependent on whether or not brain networks are dynamic. This is the first comprehensive study to evaluate multiple network metrics at a voxel-wise resolution in the human brain at both the whole brain and regional level under various conditions: resting state, visual stimulation, and multisensory (auditory and visual stimulation. Our results show that despite global network stability, functional brain networks exhibit considerable task-induced changes in connectivity, efficiency, and community structure at the regional level.

  17. Low putamen activity associated with poor reward sensitivity in childhood chronic fatigue syndrome

    Directory of Open Access Journals (Sweden)

    Kei Mizuno, Ph.D.

    2016-01-01

    Full Text Available Motivational signals influence a wide variety of cognitive processes and components of behavioral performance. Cognitive dysfunction in patients with childhood chronic fatigue syndrome (CCFS may be closely associated with a low motivation to learn induced by impaired neural reward processing. However, the extent to which reward processing is impaired in CCFS patients is unclear. The aim of the present functional magnetic resonance imaging (fMRI study was to determine whether brain activity in regions related to reward sensitivity is impaired in CCFS patients. fMRI data were collected from 13 CCFS patients (mean age, 13.6 ± 1.0 years and 13 healthy children and adolescents (HCA (mean age, 13.7 ± 1.3 years performing a monetary reward task. Neural activity in high- and low-monetary-reward conditions was compared between CCFS and HCA groups. Severity of fatigue and the reward obtained from learning in daily life were evaluated by questionnaires. Activity of the putamen was lower in the CCFS group than in the HCA group in the low-reward condition, but not in the high-reward condition. Activity of the putamen in the low-reward condition in CCFS patients was negatively and positively correlated with severity of fatigue and the reward from learning in daily life, respectively. We previously revealed that motivation to learn was correlated with striatal activity, particularly the neural activity in the putamen. This suggests that in CCFS patients low putamen activity, associated with altered dopaminergic function, decreases reward sensitivity and lowers motivation to learn.

  18. Low putamen activity associated with poor reward sensitivity in childhood chronic fatigue syndrome.

    Science.gov (United States)

    Mizuno, Kei; Kawatani, Junko; Tajima, Kanako; Sasaki, Akihiro T; Yoneda, Tetsuya; Komi, Masanori; Hirai, Toshinori; Tomoda, Akemi; Joudoi, Takako; Watanabe, Yasuyoshi

    2016-01-01

    Motivational signals influence a wide variety of cognitive processes and components of behavioral performance. Cognitive dysfunction in patients with childhood chronic fatigue syndrome (CCFS) may be closely associated with a low motivation to learn induced by impaired neural reward processing. However, the extent to which reward processing is impaired in CCFS patients is unclear. The aim of the present functional magnetic resonance imaging (fMRI) study was to determine whether brain activity in regions related to reward sensitivity is impaired in CCFS patients. fMRI data were collected from 13 CCFS patients (mean age, 13.6 ± 1.0 years) and 13 healthy children and adolescents (HCA) (mean age, 13.7 ± 1.3 years) performing a monetary reward task. Neural activity in high- and low-monetary-reward conditions was compared between CCFS and HCA groups. Severity of fatigue and the reward obtained from learning in daily life were evaluated by questionnaires. Activity of the putamen was lower in the CCFS group than in the HCA group in the low-reward condition, but not in the high-reward condition. Activity of the putamen in the low-reward condition in CCFS patients was negatively and positively correlated with severity of fatigue and the reward from learning in daily life, respectively. We previously revealed that motivation to learn was correlated with striatal activity, particularly the neural activity in the putamen. This suggests that in CCFS patients low putamen activity, associated with altered dopaminergic function, decreases reward sensitivity and lowers motivation to learn.

  19. Dopamine in motivational control: rewarding, aversive, and alerting.

    Science.gov (United States)

    Bromberg-Martin, Ethan S; Matsumoto, Masayuki; Hikosaka, Okihide

    2010-12-09

    Midbrain dopamine neurons are well known for their strong responses to rewards and their critical role in positive motivation. It has become increasingly clear, however, that dopamine neurons also transmit signals related to salient but nonrewarding experiences such as aversive and alerting events. Here we review recent advances in understanding the reward and nonreward functions of dopamine. Based on this data, we propose that dopamine neurons come in multiple types that are connected with distinct brain networks and have distinct roles in motivational control. Some dopamine neurons encode motivational value, supporting brain networks for seeking, evaluation, and value learning. Others encode motivational salience, supporting brain networks for orienting, cognition, and general motivation. Both types of dopamine neurons are augmented by an alerting signal involved in rapid detection of potentially important sensory cues. We hypothesize that these dopaminergic pathways for value, salience, and alerting cooperate to support adaptive behavior.

  20. Effects and mechanisms of 3α,5α,-THP on emotion, motivation, and reward functions involving pregnane xenobiotic receptor

    Directory of Open Access Journals (Sweden)

    Cheryl A Frye

    2012-01-01

    Full Text Available Progestogens [progesterone (P4 and its products] play fundamental roles in the development and/or function of the central nervous system during pregnancy. We, and others, have investigated the role of pregnane neurosteroids for a plethora of functional effects beyond their pro-gestational processes. Emerging findings regarding the effects, mechanisms, and sources of neurosteroids have challenged traditional dogma about steroid action. How the P4 metabolite and neurosteroid, 3α-hydroxy-5α-pregnan-20-one (3α,5α-THP, influences cellular functions and behavioral processes involved in emotion/affect, motivation, and reward, is the focus of the present review. To further understand these processes, we have utilized an animal model assessing the effects, mechanisms, and sources of 3α,5α-THP. In the ventral tegmental area (VTA, 3α,5α-THP has actions to facilitate affective, and motivated, social behaviors through non-traditional targets, such as GABA, glutamate, and dopamine receptors. 3α,5α-THP levels in the midbrain VTA both facilitate, and/or are enhanced by, affective and social behavior. The pregnane xenobiotic receptor (PXR mediates the production of, and/or metabolism to, various neurobiological factors. PXR is localized to the midbrain VTA of rats. The role of PXR to influence 3α,5α-THP production from central biosynthesis, and/or metabolism of peripheral P4, in the VTA, as well as its role to facilitate, or be increased by, affective/social behaviors is under investigation. Investigating novel behavioral functions of 3α,5α-THP extends our knowledge of the neurobiology of progestogens, relevant for affective/social behaviors, and their connections to systems that regulate affect and motivated processes, such as those important for stress regulation and neuropsychiatric disorders (anxiety, depression, schizophrenia, drug dependence. Thus, further understanding of 3α,5α-THP’s role and mechanisms to enhance affective and motivated

  1. Effects and Mechanisms of 3α,5α,-THP on Emotion, Motivation, and Reward Functions Involving Pregnane Xenobiotic Receptor.

    Science.gov (United States)

    Frye, Cheryl A; Paris, J J; Walf, A A; Rusconi, J C

    2011-01-01

    Progestogens [progesterone (P(4)) and its products] play fundamental roles in the development and/or function of the central nervous system during pregnancy. We, and others, have investigated the role of pregnane neurosteroids for a plethora of functional effects beyond their pro-gestational processes. Emerging findings regarding the effects, mechanisms, and sources of neurosteroids have challenged traditional dogma about steroid action. How the P(4) metabolite and neurosteroid, 3α-hydroxy-5α-pregnan-20-one (3α,5α-THP), influences cellular functions and behavioral processes involved in emotion/affect, motivation, and reward, is the focus of the present review. To further understand these processes, we have utilized an animal model assessing the effects, mechanisms, and sources of 3α,5α-THP. In the ventral tegmental area (VTA), 3α,5α-THP has actions to facilitate affective, and motivated, social behaviors through non-traditional targets, such as GABA, glutamate, and dopamine receptors. 3α,5α-THP levels in the midbrain VTA both facilitate, and/or are enhanced by, affective and social behavior. The pregnane xenobiotic receptor (PXR) mediates the production of, and/or metabolism to, various neurobiological factors. PXR is localized to the midbrain VTA of rats. The role of PXR to influence 3α,5α-THP production from central biosynthesis, and/or metabolism of peripheral P(4), in the VTA, as well as its role to facilitate, or be increased by, affective/social behaviors is under investigation. Investigating novel behavioral functions of 3α,5α-THP extends our knowledge of the neurobiology of progestogens, relevant for affective/social behaviors, and their connections to systems that regulate affect and motivated processes, such as those important for stress regulation and neuropsychiatric disorders (anxiety, depression, schizophrenia, drug dependence). Thus, further understanding of 3α,5α-THP's role and mechanisms to enhance affective and motivated processes

  2. Amygdaloid projections to the ventral striatum in mice: Direct and indirect chemosensory inputs to the brain reward system

    Directory of Open Access Journals (Sweden)

    Amparo eNovejarque

    2011-08-01

    Full Text Available Rodents constitute good models for studying the neural basis of socio-sexual behaviour. Recent findings in mice have revealed the molecular identity of the some pheromonal molecules triggering intersexual attraction. However, the neural pathways mediating this basic socio-sexual behaviour remain elusive. Since previous work indicates that the dopaminergic tegmento-striatal pathway is not involved in pheromone reward, the present report explores alternative pathways linking the vomeronasal system with the tegmento-striatal system (the limbic basal ganglia by means of tract-tracing experiments studying direct and indirect projections from the chemosensory amygdala to the ventral striato-pallidum. Amygdaloid projections to the nucleus accumbens, olfactory tubercle and adjoining structures are studied by analysing the retrograde transport in the amygdala from dextranamine and fluorogold injections in the ventral striatum, as well as the anterograde labelling found in the ventral striato-pallidum after dextranamine injections in the amgydala. This combination of anterograde and retrograde tracing experiments reveals direct projections from the vomeronasal cortex to the ventral striato-pallidum, as well as indirect projections through different nuclei of the basolateral amygdala. Direct projections innervate mainly the olfactory tubercle and the islands of Calleja, whereas indirect projections are more widespread and reach the same structures and the shell and core of nucleus accumbens. These pathways are likely to mediate innate responses to pheromones (direct projections and conditioned responses to associated chemosensory and non-chemosensory stimuli (indirect projections. Comparative studies indicate that similar connections are present in all the studied amniote vertebrates and might constitute the basic circuitry for emotional responses to conspecifics in most vertebrates, including humans.

  3. The modular and integrative functional architecture of the human brain.

    Science.gov (United States)

    Bertolero, Maxwell A; Yeo, B T Thomas; D'Esposito, Mark

    2015-12-01

    Network-based analyses of brain imaging data consistently reveal distinct modules and connector nodes with diverse global connectivity across the modules. How discrete the functions of modules are, how dependent the computational load of each module is to the other modules' processing, and what the precise role of connector nodes is for between-module communication remains underspecified. Here, we use a network model of the brain derived from resting-state functional MRI (rs-fMRI) data and investigate the modular functional architecture of the human brain by analyzing activity at different types of nodes in the network across 9,208 experiments of 77 cognitive tasks in the BrainMap database. Using an author-topic model of cognitive functions, we find a strong spatial correspondence between the cognitive functions and the network's modules, suggesting that each module performs a discrete cognitive function. Crucially, activity at local nodes within the modules does not increase in tasks that require more cognitive functions, demonstrating the autonomy of modules' functions. However, connector nodes do exhibit increased activity when more cognitive functions are engaged in a task. Moreover, connector nodes are located where brain activity is associated with many different cognitive functions. Connector nodes potentially play a role in between-module communication that maintains the modular function of the brain. Together, these findings provide a network account of the brain's modular yet integrated implementation of cognitive functions.

  4. Hot executive function in children with developmental coordination disorder: Evidence for heightened sensitivity to immediate reward

    NARCIS (Netherlands)

    Rahimi-Golkhandan, S.; Piek, J.P.; Steenbergen, B.; Wilson, P.H.

    2014-01-01

    Deficits of cool executive function (EF) have been shown in children with motor problems (or Developmental Coordination Disorder – DCD), but little is known of hot EF in this group. Given some evidence of poor self-regulation in DCD, we predicted poorer performance on a measure of hot EF, the Hungry

  5. Functional brain imaging of gastrointestinal sensation in health and disease

    Institute of Scientific and Technical Information of China (English)

    Lukas Van Oudenhove; Steven J Coen; Qasim Aziz

    2007-01-01

    It has since long been known, from everyday experience as well as from animal and human studies, that psychological processes-both affective and cognitiveexert an influence on gastrointestinal sensorimotor function. More specifically, a link between psychological factors and visceral hypersensitivity has been suggested,mainly based on research in functional gastrointestinal disorder patients. However, until recently, the exact nature of this putative relationship remained unclear,mainly due to a lack of non-invasive methods to study the (neurobiological) mechanisms underlying this relationship in non-sleeping humans. As functional brain imaging, introduced in visceral sensory neuroscience some 10 years ago, does provide a method for in vivo study of brain-gut interactions, insight into the neurobiological mechanisms underlying visceral sensation in general and the influence of psychological factors more particularly,has rapidly grown. In this article, an overview of brain imaging evidence on gastrointestinal sensation will be given, with special emphasis on the brain mechanisms underlying the interaction between affective & cognitive processes and visceral sensation. First, the reciprocal neural pathways between the brain and the gut (braingut axis) will be briefly outlined, including brain imaging evidence in healthy volunteers. Second, functional brain imaging studies assessing the influence of psychological factors on brain processing of visceral sensation in healthy humans will be discussed in more detail.Finally, brain imaging work investigating differences in brain responses to visceral distension between healthy volunteers and functional gastrointestinal disorder patients will be highlighted.

  6. Infrared Imaging System for Studying Brain Function

    Science.gov (United States)

    Mintz, Frederick; Mintz, Frederick; Gunapala, Sarath

    2007-01-01

    A proposed special-purpose infrared imaging system would be a compact, portable, less-expensive alternative to functional magnetic resonance imaging (fMRI) systems heretofore used to study brain function. Whereas a typical fMRI system fills a large room, and must be magnetically isolated, this system would fit into a bicycle helmet. The system would include an assembly that would be mounted inside the padding in a modified bicycle helmet or other suitable headgear. The assembly would include newly designed infrared photodetectors and data-acquisition circuits on integrated-circuit chips on low-thermal-conductivity supports in evacuated housings (see figure) arranged in multiple rows and columns that would define image coordinates. Each housing would be spring-loaded against the wearer s head. The chips would be cooled by a small Stirling Engine mounted contiguous to, but thermally isolated from, the portions of the assembly in thermal contact with the wearer s head. Flexible wires or cables for transmitting data from the aforementioned chips would be routed to an integrated, multichannel transmitter and thence through the top of the assembly to a patch antenna on the outside of the helmet. The multiple streams of data from the infrared-detector chips would be sent to a remote site, where they would be processed, by software, into a three-dimensional display of evoked potentials that would represent firing neuronal bundles and thereby indicate locations of neuronal activity associated with mental or physical activity. The 3D images will be analogous to current fMRI images. The data would also be made available, in real-time, for comparison with data in local or internationally accessible relational databases that already exist in universities and research centers. Hence, this system could be used in research on, and for the diagnosis of response from the wearer s brain to physiological, psychological, and environmental changes in real time. The images would also be

  7. Three-dimensional reconstruction of functional brain images

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Masato; Shoji, Kazuhiko; Kojima, Hisayoshi; Hirano, Shigeru; Naito, Yasushi; Honjo, Iwao [Kyoto Univ. (Japan)

    1999-08-01

    We consider PET (positron emission tomography) measurement with SPM (Statistical Parametric Mapping) analysis to be one of the most useful methods to identify activated areas of the brain involved in language processing. SPM is an effective analytical method that detects markedly activated areas over the whole brain. However, with the conventional presentations of these functional brain images, such as horizontal slices, three directional projection, or brain surface coloring, makes understanding and interpreting the positional relationships among various brain areas difficult. Therefore, we developed three-dimensionally reconstructed images from these functional brain images to improve the interpretation. The subjects were 12 normal volunteers. The following three types of images were constructed: routine images by SPM, three-dimensional static images, and three-dimensional dynamic images, after PET images were analyzed by SPM during daily dialog listening. The creation of images of both the three-dimensional static and dynamic types employed the volume rendering method by VTK (The Visualization Toolkit). Since the functional brain images did not include original brain images, we synthesized SPM and MRI brain images by self-made C++ programs. The three-dimensional dynamic images were made by sequencing static images with available software. Images of both the three-dimensional static and dynamic types were processed by a personal computer system. Our newly created images showed clearer positional relationships among activated brain areas compared to the conventional method. To date, functional brain images have been employed in fields such as neurology or neurosurgery, however, these images may be useful even in the field of otorhinolaryngology, to assess hearing and speech. Exact three-dimensional images based on functional brain images are important for exact and intuitive interpretation, and may lead to new developments in brain science. Currently, the surface

  8. Developing a Comprehensive Reward System.

    Science.gov (United States)

    Votruba, James C.

    1979-01-01

    Providing incentives for teachers of adults is an important means of attracting, retaining, and stimulating staff. Developing a variety of extrinsic and intrinsic rewards and incentives and instituting them effectively are important administrative functions. (SK)

  9. Rewarding prayers.

    Science.gov (United States)

    Schjødt, Uffe; Stødkilde-Jørgensen, Hans; Geertz, Armin W; Roepstorff, Andreas

    2008-10-10

    We report a highly significant regional increase of the BOLD response in the caudate nucleus in a group of Danish Christians while performing silent religious prayer. The effect was found in a main-effect analysis of high-structured and low-structured religious recitals relative to comparable secular recitals and to a non-narrative baseline. This supports the hypothesis that religious prayer as a form of frequently recurring behavior is capable of stimulating the dopaminergic reward system in practicing individuals. It extends recent research which demonstrates a relation between interpersonal trust and activation in the dopaminergic system to also encompass relations to abstract entities.

  10. Cognitive strategies regulate fictive, but not reward prediction error signals in a sequential investment task.

    Science.gov (United States)

    Gu, Xiaosi; Kirk, Ulrich; Lohrenz, Terry M; Montague, P Read

    2014-08-01

    Computational models of reward processing suggest that foregone or fictive outcomes serve as important information sources for learning and augment those generated by experienced rewards (e.g. reward prediction errors). An outstanding question is how these learning signals interact with top-down cognitive influences, such as cognitive reappraisal strategies. Using a sequential investment task and functional magnetic resonance imaging, we show that the reappraisal strategy selectively attenuates the influence of fictive, but not reward prediction error signals on investment behavior; such behavioral effect is accompanied by changes in neural activity and connectivity in the anterior insular cortex, a brain region thought to integrate subjective feelings with high-order cognition. Furthermore, individuals differ in the extent to which their behaviors are driven by fictive errors versus reward prediction errors, and the reappraisal strategy interacts with such individual differences; a finding also accompanied by distinct underlying neural mechanisms. These findings suggest that the variable interaction of cognitive strategies with two important classes of computational learning signals (fictive, reward prediction error) represent one contributing substrate for the variable capacity of individuals to control their behavior based on foregone rewards. These findings also expose important possibilities for understanding the lack of control in addiction based on possibly foregone rewarding outcomes.

  11. Post-learning Hippocampal Dynamics Promote Preferential Retention of Rewarding Events.

    Science.gov (United States)

    Gruber, Matthias J; Ritchey, Maureen; Wang, Shao-Fang; Doss, Manoj K; Ranganath, Charan

    2016-03-01

    Reward motivation is known to modulate memory encoding, and this effect depends on interactions between the substantia nigra/ventral tegmental area complex (SN/VTA) and the hippocampus. It is unknown, however, whether these interactions influence offline neural activity in the human brain that is thought to promote memory consolidation. Here we used fMRI to test the effect of reward motivation on post-learning neural dynamics and subsequent memory for objects that were learned in high- and low-reward motivation contexts. We found that post-learning increases in resting-state functional connectivity between the SN/VTA and hippocampus predicted preferential retention of objects that were learned in high-reward contexts. In addition, multivariate pattern classification revealed that hippocampal representations of high-reward contexts were preferentially reactivated during post-learning rest, and the number of hippocampal reactivations was predictive of preferential retention of items learned in high-reward contexts. These findings indicate that reward motivation alters offline post-learning dynamics between the SN/VTA and hippocampus, providing novel evidence for a potential mechanism by which reward could influence memory consolidation.

  12. MicroRNA expression profiles and functions in the brain

    Institute of Scientific and Technical Information of China (English)

    Yanting Qi; Yu Zhao; Zhuyin Chen; Xiaona Chen; Marie C. Lin; Xiangfu Kong; Lihui Lai

    2008-01-01

    MicroRNAs are abundant in the brains of vertebrates and some show a brain-specific or brain-enriched expression pattern. Because microRNAs regulate the expression of hundreds of target genes, it is not surprising that they have profoundly important functions in brain development and pathological processes. For example, miR-124 plays an important role in inducing and maintaining neuronal identity through targeting at least two anti-neural factors. MicroRNAs have also been implicated in brain disorders, including brain tumors and neurodegenerative diseases. This review aims to present an overview of the expression profiles and functions of microRNAs in the developing brains of vertebrates.

  13. Wearable sensor network to study laterality of brain functions.

    Science.gov (United States)

    Postolache, Gabriela B; Girao, Pedro S; Postolache, Octavian A

    2015-08-01

    In the last decade researches on laterality of brain functions have been reinvigorated. New models of lateralization of brain functions were proposed and new methods for understanding mechanisms of asymmetry between right and left brain functions were described. We design a system to study laterality of motor and autonomic nervous system based on wearable sensors network. A mobile application was developed for analysis of upper and lower limbs movements, cardiac and respiratory function. The functionalities and experience gained with deployment of the system are described.

  14. Persistent Postconcussive Symptoms Are Accompanied by Decreased Functional Brain Oxygenation.

    Science.gov (United States)

    Helmich, Ingo; Saluja, Rajeet S; Lausberg, Hedda; Kempe, Mathias; Furley, Philip; Berger, Alisa; Chen, Jen-Kai; Ptito, Alain

    2015-01-01

    Diagnostic methods are considered a major concern in the determination of mild traumatic brain injury. The authors examined brain oxygenation patterns in subjects with severe and minor persistent postconcussive difficulties and a healthy control group during working memory tasks in prefrontal brain regions using functional near-infrared spectroscopy. The results demonstrated decreased working memory performances among concussed subjects with severe postconcussive symptoms that were accompanied by decreased brain oxygenation patterns. An association appears to exist between decreased brain oxygenation, poor performance of working memory tasks, and increased symptom severity scores in subjects suffering from persistent postconcussive symptoms.

  15. Pathological anxiety and function/dysfunction in the brain's fear/defense circuitry.

    Science.gov (United States)

    Lang, Peter J; McTeague, Lisa M; Bradley, Margaret M

    2014-01-01

    Research from the University of Florida Center for the Study of Emotion and Attention aims to develop neurobiological measures that objectively discriminate among symptom patterns in patients with anxiety disorders. From this perspective, anxiety and mood pathologies are considered to be brain disorders, resulting from dysfunction and maladaptive plasticity in the neural circuits that determine fearful/defensive and appetitive/reward behavior (Insel et al., 2010). We review recent studies indicating that an enhanced probe startle reflex during the processing of fear memory cues (mediated by cortico-limbic circuitry and thus indicative of plastic brain changes), varies systematically in strength over a spectrum-wide dimension of anxiety pathology-across and within diagnoses-extending from strong focal fear reactions to a consistently blunted reaction in patients with more generalized anxiety and comorbid mood disorders. Preliminary studies with functional magnetic resonance imaging (fMRI) encourage the hypothesis that fear/defense circuit dysfunction covaries with this same dimension of psychopathology. Plans are described for an extended study of the brain's motivation circuitry in anxiety spectrum patients, with the aim of defining the specifics of circuit dysfunction in severe disorders. A sub-project explores the use of real-time fMRI feedback in circuit analysis and as a modality to up-regulate circuit function in the context of blunted affect.

  16. Manifold learning on brain functional networks in aging.

    Science.gov (United States)

    Qiu, Anqi; Lee, Annie; Tan, Mingzhen; Chung, Moo K

    2015-02-01

    We propose a new analysis framework to utilize the full information of brain functional networks for computing the mean of a set of brain functional networks and embedding brain functional networks into a low-dimensional space in which traditional regression and classification analyses can be easily employed. For this, we first represent the brain functional network by a symmetric positive matrix computed using sparse inverse covariance estimation. We then impose a Log-Euclidean Riemannian manifold structure on brain functional networks whose norm gives a convenient and practical way to define a mean. Finally, based on the fact that the computation of linear operations can be done in the tangent space of this Riemannian manifold, we adopt Locally Linear Embedding (LLE) to the Log-Euclidean Riemannian manifold space in order to embed the brain functional networks into a low-dimensional space. We show that the integration of the Log-Euclidean manifold with LLE provides more efficient and succinct representation of the functional network and facilitates regression analysis, such as ridge regression, on the brain functional network to more accurately predict age when compared to that of the Euclidean space of functional networks with LLE. Interestingly, using the Log-Euclidean analysis framework, we demonstrate the integration and segregation of cortical-subcortical networks as well as among the salience, executive, and emotional networks across lifespan.

  17. The dynamic dielectric at a brain functional site and an EM wave approach to functional brain imaging.

    Science.gov (United States)

    Li, X P; Xia, Q; Qu, D; Wu, T C; Yang, D G; Hao, W D; Jiang, X; Li, X M

    2014-11-04

    Functional brain imaging has tremendous applications. The existing methods for functional brain imaging include functional Magnetic Resonant Imaging (fMRI), scalp electroencephalography (EEG), implanted EEG, magnetoencephalography (MEG) and Positron Emission Tomography (PET), which have been widely and successfully applied to various brain imaging studies. To develop a new method for functional brain imaging, here we show that the dielectric at a brain functional site has a dynamic nature, varying with local neuronal activation as the permittivity of the dielectric varies with the ion concentration of the extracellular fluid surrounding neurons in activation. Therefore, the neuronal activation can be sensed by a radiofrequency (RF) electromagnetic (EM) wave propagating through the site as the phase change of the EM wave varies with the permittivity. Such a dynamic nature of the dielectric at a brain functional site provides the basis for an RF EM wave approach to detecting and imaging neuronal activation at brain functional sites, leading to an RF EM wave approach to functional brain imaging.

  18. Development of large-scale functional brain networks in children.

    Directory of Open Access Journals (Sweden)

    Kaustubh Supekar

    2009-07-01

    Full Text Available The ontogeny of large-scale functional organization of the human brain is not well understood. Here we use network analysis of intrinsic functional connectivity to characterize the organization of brain networks in 23 children (ages 7-9 y and 22 young-adults (ages 19-22 y. Comparison of network properties, including path-length, clustering-coefficient, hierarchy, and regional connectivity, revealed that although children and young-adults' brains have similar "small-world" organization at the global level, they differ significantly in hierarchical organization and interregional connectivity. We found that subcortical areas were more strongly connected with primary sensory, association, and paralimbic areas in children, whereas young-adults showed stronger cortico-cortical connectivity between paralimbic, limbic, and association areas. Further, combined analysis of functional connectivity with wiring distance measures derived from white-matter fiber tracking revealed that the development of large-scale brain networks is characterized by weakening of short-range functional connectivity and strengthening of long-range functional connectivity. Importantly, our findings show that the dynamic process of over-connectivity followed by pruning, which rewires connectivity at the neuronal level, also operates at the systems level, helping to reconfigure and rebalance subcortical and paralimbic connectivity in the developing brain. Our study demonstrates the usefulness of network analysis of brain connectivity to elucidate key principles underlying functional brain maturation, paving the way for novel studies of disrupted brain connectivity in neurodevelopmental disorders such as autism.

  19. Functional brain imaging studies on specificity of meridian and acupoints

    Institute of Scientific and Technical Information of China (English)

    Xuezhi Li; Xuguang Liu; Fanrong Liang

    2008-01-01

    At present,the specificity of meridians and acupoints has been studied using functional brain imaging techniques from many standpoints.including meridians,acupoints,and sham acupoints,as well as different meridians and acupoints,coordination of acupoints,and factors influencing meridian and acupoint specificity.Preliminary experimental data have demonstrated that acupuncture at meridians and acupoints is specific with regard to brain neural information.However,research findings are contradictory,which may be related to brain functional complexity,resolution of functional brain imaging techniques,and experimental design.Future studies should further improve study method,and should strictly control experimental conditions to better analyze experimental data and acquire more beneficial data.Because of its many advantages.the functional brain imaging technique is a promising method for studying meridian and acupoint specificity.

  20. Neuroticism and Functional Connectomics of the Resting Adolescent Brain

    DEFF Research Database (Denmark)

    Baruël Johansen, Louise

    network organization on the global level, while network characteristics of fronto-limbic regions, involved in emotional processing, are implicated on a local level. Little is known about neuroticism and functional brain organization in childhood and adolescence. The main aim of this thesis was therefore......The personality trait neuroticism is a well-known risk factor for anxiety and mood disorders that typically have their onset in childhood and adolescence. This period is characterized by ongoing structural and functional maturation of the brain, which can be traced with magnetic resonance imaging...... (MRI). Resting-state functional MRI is a widely used technique for studies of brain development due to the task-free condition. Furthermore, this imaging modality can be used to study the functional network of the brain that subserves communication between regions of the brain. Properties...

  1. Serotonergic modulation of reward and punishment

    DEFF Research Database (Denmark)

    Macoveanu, Julian

    2014-01-01

    Until recently, the bulk of research on the human reward system was focused on studying the dopaminergic and opioid neurotransmitter systems. However, extending the initial data from animal studies on reward, recent pharmacological brain imaging studies on human participants bring a new line...... of evidence on the key role serotonin plays in reward processing. The reviewed research has revealed how central serotonin availability and receptor specific transmission modulates the neural response to both appetitive (rewarding) and aversive (punishing) stimuli in putative reward-related brain regions......-related processing and may also provide a neural correlated for the emotional blunting observed in the clinical treatment of psychiatric disorders with selective serotonin reuptake inhibitors. Given the unique profile of action of each serotonergic receptor subtype, future pharmacological studies may favor receptor...

  2. The effects of vitamin D on brain development and adult brain function.

    Science.gov (United States)

    Kesby, James P; Eyles, Darryl W; Burne, Thomas H J; McGrath, John J

    2011-12-05

    A role for vitamin D in brain development and function has been gaining support over the last decade. Multiple lines of evidence suggest that this vitamin is actually a neuroactive steroid that acts on brain development, leading to alterations in brain neurochemistry and adult brain function. Early deficiencies have been linked with neuropsychiatric disorders, such as schizophrenia, and adult deficiencies have been associated with a host of adverse brain outcomes, including Parkinson's disease, Alzheimer's disease, depression and cognitive decline. This review summarises the current state of research on the actions of vitamin D in the brain and the consequences of deficiencies in this vitamin. Furthermore, we discuss specific implications of vitamin D status on the neurotransmitter, dopamine.

  3. Connectivity and functional profiling of abnormal brain structures in pedophilia.

    Science.gov (United States)

    Poeppl, Timm B; Eickhoff, Simon B; Fox, Peter T; Laird, Angela R; Rupprecht, Rainer; Langguth, Berthold; Bzdok, Danilo

    2015-06-01

    Despite its 0.5-1% lifetime prevalence in men and its general societal relevance, neuroimaging investigations in pedophilia are scarce. Preliminary findings indicate abnormal brain structure and function. However, no study has yet linked structural alterations in pedophiles to both connectional and functional properties of the aberrant hotspots. The relationship between morphological alterations and brain function in pedophilia as well as their contribution to its psychopathology thus remain unclear. First, we assessed bimodal connectivity of structurally altered candidate regions using meta-analytic connectivity modeling (MACM) and resting-state correlations employing openly accessible data. We compared the ensuing connectivity maps to the activation likelihood estimation (ALE) maps of a recent quantitative meta-analysis of brain activity during processing of sexual stimuli. Second, we functionally characterized the structurally altered regions employing meta-data of a large-scale neuroimaging database. Candidate regions were functionally connected to key areas for processing of sexual stimuli. Moreover, we found that the functional role of structurally altered brain regions in pedophilia relates to nonsexual emotional as well as neurocognitive and executive functions, previously reported to be impaired in pedophiles. Our results suggest that structural brain alterations affect neural networks for sexual processing by way of disrupted functional connectivity, which may entail abnormal sexual arousal patterns. The findings moreover indicate that structural alterations account for common affective and neurocognitive impairments in pedophilia. The present multimodal integration of brain structure and function analyses links sexual and nonsexual psychopathology in pedophilia.

  4. Connectivity and functional profiling of abnormal brain structures in pedophilia

    Science.gov (United States)

    Poeppl, Timm B.; Eickhoff, Simon B.; Fox, Peter T.; Laird, Angela R.; Rupprecht, Rainer; Langguth, Berthold; Bzdok, Danilo

    2015-01-01

    Despite its 0.5–1% lifetime prevalence in men and its general societal relevance, neuroimaging investigations in pedophilia are scarce. Preliminary findings indicate abnormal brain structure and function. However, no study has yet linked structural alterations in pedophiles to both connectional and functional properties of the aberrant hotspots. The relationship between morphological alterations and brain function in pedophilia as well as their contribution to its psychopathology thus remain unclear. First, we assessed bimodal connectivity of structurally altered candidate regions using meta-analytic connectivity modeling (MACM) and resting-state correlations employing openly accessible data. We compared the ensuing connectivity maps to the activation likelihood estimation (ALE) maps of a recent quantitative meta-analysis of brain activity during processing of sexual stimuli. Second, we functionally characterized the structurally altered regions employing meta-data of a large-scale neuroimaging database. Candidate regions were functionally connected to key areas for processing of sexual stimuli. Moreover, we found that the functional role of structurally altered brain regions in pedophilia relates to nonsexual emotional as well as neurocognitive and executive functions, previously reported to be impaired in pedophiles. Our results suggest that structural brain alterations affect neural networks for sexual processing by way of disrupted functional connectivity, which may entail abnormal sexual arousal patterns. The findings moreover indicate that structural alterations account for common affective and neurocognitive impairments in pedophilia. The present multi-modal integration of brain structure and function analyses links sexual and nonsexual psychopathology in pedophilia. PMID:25733379

  5. Localization of the brain calculation function area with MRI

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The aim of this study is to define the anatomical localization of corresponding brain function area during calculating. The activating modes in brain during continuous silent calculating subtraction and repeated silent reading multiplication table were compared and investigated. Fourteen volunteers of right-handedness were enrolled in this experiment. The quite difference of reaction modes in brain area during the two modes of calculation reveal that there are different processing pathways in brain during these two operating actions. During continuous silent calculating, the function area is localized on the posterior portion of superior and middle gyrus of frontal lobe and the Iobule of posterior parietal lobe (P < 0.01, T = 5.41). It demonstrates that these function areas play an important role in the performance of calculation and working memory. Whereas the activating of visual cortex shows that even in mental arithmetic processing the brain action is having the aid of vision and visual space association.

  6. Acute stress-induced cortisol elevations mediate reward system activity during subconscious processing of sexual stimuli.

    Science.gov (United States)

    Oei, Nicole Y L; Both, Stephanie; van Heemst, Diana; van der Grond, Jeroen

    2014-01-01

    Stress is thought to alter motivational processes by increasing dopamine (DA) secretion in the brain's "reward system", and its key region, the nucleus accumbens (NAcc). However, stress studies using functional magnetic resonance imaging (fMRI), mainly found evidence for stress-induced decreases in NAcc responsiveness toward reward cues. Results from both animal and human PET studies indicate that the stress hormone cortisol may be crucial in the interaction between stress and dopaminergic actions. In the present study we therefore investigated whether cortisol mediated the effect of stress on DA-related responses to -subliminal-presentation of reward cues using the Trier Social Stress Test (TSST), which is known to reliably enhance cortisol levels. Young healthy males (n = 37) were randomly assigned to the TSST or control condition. After stress induction, brain activation was assessed using fMRI during a backward-masking paradigm in which potentially rewarding (sexual), emotionally negative and neutral stimuli were presented subliminally, masked by pictures of inanimate objects. A region of interest analysis showed that stress decreased activation in the NAcc in response to masked sexual cues (voxel-corrected, pcortisol levels were related to stronger NAcc activation, showing that cortisol acted as a suppressor variable in the negative relation between stress and NAcc activation. The present findings indicate that cortisol is crucially involved in the relation between stress and the responsiveness of the reward system. Although generally stress decreases activation in the NAcc in response to rewarding stimuli, high stress-induced cortisol levels suppress this relation, and are associated with stronger NAcc activation. Individuals with a high cortisol response to stress might on one hand be protected against reductions in reward sensitivity, which has been linked to anhedonia and depression, but they may ultimately be more vulnerable to increased reward

  7. A probabilistic approach to delineating functional brain regions

    DEFF Research Database (Denmark)

    Kalbitzer, Jan; Svarer, Claus; Frokjaer, Vibe G

    2009-01-01

    The purpose of this study was to develop a reliable observer-independent approach to delineating volumes of interest (VOIs) for functional brain regions that are not identifiable on structural MR images. The case is made for the raphe nuclei, a collection of nuclei situated in the brain stem known......-independent, reliable approach to delineating regions that can be identified only by functional imaging, here exemplified by the raphe nuclei. This approach can be used in future studies to create functional VOI maps based on neuroreceptor fingerprints retrieved through in vivo brain imaging Udgivelsesdato: 2009/6...

  8. Functional brain laterality for sequential movements: Impact of transient practice

    Institute of Scientific and Technical Information of China (English)

    ZHU Yihong; DONG Zongwang; WENG Xuchu; CHEN Yizhang

    2005-01-01

    The impact of learning on brain functional laterality has not been systematically investigated. We employed an event-related functional magnetic resonance imaging combined with a delayed sequential movement task to investigate brain activation pattern and laterality during a transient practice in 12 subjects. Both hemispheres, involving motor areas and posterior parietal cortex, were engaged during motor preparation and execution, with larger activation volume in the left hemisphere than in the right. Activation volume in these regions significantly decreased after a transient practice, with more reduction in the right hemisphere resulting increase in left lateralization. The theoretical implications of these findings are discussed in relation to the physiological significance of brain functional laterality.

  9. Neural correlates of reward-based spatial learning in persons with cocaine dependence.

    Science.gov (United States)

    Tau, Gregory Z; Marsh, Rachel; Wang, Zhishun; Torres-Sanchez, Tania; Graniello, Barbara; Hao, Xuejun; Xu, Dongrong; Packard, Mark G; Duan, Yunsuo; Kangarlu, Alayar; Martinez, Diana; Peterson, Bradley S

    2014-02-01

    Dysfunctional learning systems are thought to be central to the pathogenesis of and impair recovery from addictions. The functioning of the brain circuits for episodic memory or learning that support goal-directed behavior has not been studied previously in persons with cocaine dependence (CD). Thirteen abstinent CD and 13 healthy participants underwent MRI scanning while performing a task that requires the use of spatial cues to navigate a virtual-reality environment and find monetary rewards, allowing the functional assessment of the brain systems for spatial learning, a form of episodic memory. Whereas both groups performed similarly on the reward-based spatial learning task, we identified disturbances in brain regions involved in learning and reward in CD participants. In particular, CD was associated with impaired functioning of medial temporal lobe (MTL), a brain region that is crucial for spatial learning (and episodic memory) with concomitant recruitment of striatum (which normally participates in stimulus-response, or habit, learning), and prefrontal cortex. CD was also associated with enhanced sensitivity of the ventral striatum to unexpected rewards but not to expected rewards earned during spatial learning. We provide evidence that spatial learning in CD is characterized by disturbances in functioning of an MTL-based system for episodic memory and a striatum-based system for stimulus-response learning and reward. We have found additional abnormalities in distributed cortical regions. Consistent with findings from animal studies, we provide the first evidence in humans describing the disruptive effects of cocaine on the coordinated functioning of multiple neural systems for learning and memory.

  10. Emotion-Induced Topological Changes in Functional Brain Networks.

    Science.gov (United States)

    Park, Chang-Hyun; Lee, Hae-Kook; Kweon, Yong-Sil; Lee, Chung Tai; Kim, Ki-Tae; Kim, Young-Joo; Lee, Kyoung-Uk

    2016-01-01

    In facial expression perception, a distributed network is activated according to stimulus context. We proposed that an interaction between brain activation and stimulus context in response to facial expressions could signify a pattern of interactivity across the whole brain network beyond the face processing network. Functional magnetic resonance imaging data were acquired for 19 young healthy subjects who were exposed to either emotionally neutral or negative facial expressions. We constructed group-wise functional brain networks for 12 face processing areas [bilateral inferior occipital gyri (IOG), fusiform gyri (FG), superior temporal sulci (STS), amygdalae (AMG), inferior frontal gyri (IFG), and orbitofrontal cortices (OFC)] and for 73 whole brain areas, based on partial correlation of mean activation across subjects. We compared the topological properties of the networks with respect to functional distance-based measures, global and local efficiency, between the two types of face stimulus. In both face processing and whole brain networks, global efficiency was lower and local efficiency was higher for negative faces relative to neutral faces, indicating that network topology differed according to stimulus context. Particularly in the face processing network, emotion-induced changes in network topology were attributable to interactions between core (bilateral IOG, FG, and STS) and extended (bilateral AMG, IFG, and OFC) systems. These results suggest that changes in brain activation patterns in response to emotional face stimuli could be revealed as changes in the topological properties of functional brain networks for the whole brain as well as for face processing areas.

  11. Functional MRI of food-induced brain responses

    NARCIS (Netherlands)

    Smeets, P.A.M.

    2006-01-01

    The ultimate goal of this research was to find central biomarkers of satiety, i.e., physiological measures in the brain that relate to subjectively rated appetite, actual food intake, or both. This thesis describes the changes in brain activity in response to food stimuli as measured by functional M

  12. DHA effects in brain development and function

    DEFF Research Database (Denmark)

    Lauritzen, Lotte; Brambilla, Paola; Mazzocchi, Allesandra;

    2016-01-01

    Docosahexaenoic acid (DHA) is a structural constituent of membranes specifically in the central nervous system. Its accumulation in the fetal brain takes place mainly during the last trimester of pregnancy and continues at very high rates up to the end of the second year of life. Since the endoge......Docosahexaenoic acid (DHA) is a structural constituent of membranes specifically in the central nervous system. Its accumulation in the fetal brain takes place mainly during the last trimester of pregnancy and continues at very high rates up to the end of the second year of life. Since...

  13. The Efficiency of a Small-World Functional Brain Network

    Institute of Scientific and Technical Information of China (English)

    ZHAO Qing-Bai; ZHANG Xiao-Fei; SUI Dan-Ni; ZHOU Zhi-Jin; CHEN Qi-Cai; TANG Yi-Yuan

    2012-01-01

    We investigate whether the small-world topology of a functional brain network means high information processing efficiency by calculating the correlation between the small-world measures of a functional brain network and behavioral reaction during an imagery task.Functional brain networks are constructed by multichannel eventrelated potential data,in which the electrodes are the nodes and the functional connectivities between them are the edges.The results show that the correlation between small-world measures and reaction time is task-specific,such that in global imagery,there is a positive correlation between the clustering coefficient and reaction time,while in local imagery the average path length is positively correlated with the reaction time.This suggests that the efficiency of a functional brain network is task-dependent.%We investigate whether the small-world topology of a functional brain network means high information processing efficiency by calculating the correlation between the small-world measures of a functional brain network and behavioral reaction during an imagery task. Functional brain networks are constructed by multichannel event-related potential data, in which the electrodes are the nodes and the functional connectivities between them are the edges. The results show that the correlation between small-world measures and reaction time is task-specific, such that in global imagery, there is a positive correlation between the clustering coefficient and reaction time, while in local imagery the average path length is positively correlated with the reaction time. This suggests that the efficiency of a functional brain network is task-dependent.

  14. Mapping functional brain development: Building a social brain through interactive specialization.

    Science.gov (United States)

    Johnson, Mark H; Grossmann, Tobias; Cohen Kadosh, Kathrin

    2009-01-01

    The authors review a viewpoint on human functional brain development, interactive specialization (IS), and its application to the emerging network of cortical regions referred to as the social brain. They advance the IS view in 2 new ways. First, they extend IS into a domain to which it has not previously been applied--the emergence of social cognition and mentalizing computations in the brain. Second, they extend the implications of the IS view from the emergence of specialized functions within a cortical region to a focus on how different cortical regions with complementary functions become orchestrated into networks during human postnatal development.

  15. Adolescent development of the reward system

    Directory of Open Access Journals (Sweden)

    Adriana Galván

    2010-02-01

    Full Text Available Adolescence is a developmental period characterized by increased reward-seeking behavior. Investigators have used functional magnetic resonance imaging (fMRI in conjunction with reward paradigms to test two opposing hypotheses about adolescent developmental changes in the striatum, a region implicated in reward processing. One hypothesis posits that the striatum is relatively hypo-responsive to rewards during adolescence, such that heightened reward-seeking behavior is necessary to achieve the same activation as adults. Another view suggests that during adolescence the striatal reward system is hyper-responsive, which subsequently results in greater reward-seeking. While evidence for both hypotheses has been reported, the field has generally converged on this latter hypothesis based on compelling evidence. In this review, I describe the evidence to support this notion, speculate on the disparate fMRI findings and conclude with future areas of inquiry to this fascinating question.

  16. Abnormal whole-brain functional networks in homogeneous acute mild traumatic brain injury.

    NARCIS (Netherlands)

    Shumskaya, E.; Andriessen, T.; Norris, D.G.; Vos, P.E.

    2012-01-01

    Objectives: To evaluate the whole-brain resting-state networks in a homogeneous group of patients with acute mild traumatic brain injury (MTBI) and to identify alterations in functional connectivity induced by MTBI. Methods: Thirty-five patients with acute MTBI and 35 healthy control subjects, mat

  17. Abnormal whole-brain functional networks in homogeneous acute mild traumatic brain injury.

    NARCIS (Netherlands)

    Shumskaya, A.N.; Andriessen, T.M.J.C.; Norris, D.G.; Vos, P.E.

    2012-01-01

    OBJECTIVES: To evaluate the whole-brain resting-state networks in a homogeneous group of patients with acute mild traumatic brain injury (MTBI) and to identify alterations in functional connectivity induced by MTBI. METHODS: Thirty-five patients with acute MTBI and 35 healthy control subjects, match

  18. Mapping Functional Brain Development: Building a Social Brain through Interactive Specialization

    Science.gov (United States)

    Johnson, Mark H.; Grossmann, Tobias; Kadosh, Kathrin Cohen

    2009-01-01

    The authors review a viewpoint on human functional brain development, interactive specialization (IS), and its application to the emerging network of cortical regions referred to as the "social brain." They advance the IS view in 2 new ways. First, they extend IS into a domain to which it has not previously been applied--the emergence of social…

  19. Reduced Caudate and Nucleus Accumbens Response to Rewards in Unmedicated Subjects with Major Depressive Disorder

    Science.gov (United States)

    Pizzagalli, Diego A.; Holmes, Avram J.; Dillon, Daniel G.; Goetz, Elena L.; Birk, Jeffrey L.; Bogdan, Ryan; Dougherty, Darin D.; Iosifescu, Dan V.; Rauch, Scott L.; Fava, Maurizio

    2009-01-01

    Objective Major depressive disorder (MDD) is characterized by impaired reward processing, possibly due to dysfunction in the basal ganglia. However, few neuroimaging studies of depression have distinguished between anticipatory and consummatory phases of reward processing. Using functional magnetic resonance imaging (fMRI) and a task that dissociates anticipatory and consummatory phases of reward processing, the authors tested the hypothesis that MDD participants would show reduced reward-related responses in basal ganglia structures. Method A monetary incentive delay task was presented to 30 unmedicated MDD subjects and 31 healthy comparison subjects during fMRI scanning. Whole-brain analyses focused on neural responses to reward-predicting cues and rewarding outcomes (i.e., monetary gains). Secondary analyses focused on the relationship between anhedonic symptoms and basal ganglia volumes. Results Relative to comparison subjects, MDD participants showed significantly weaker responses to gains in the left nucleus accumbens and bilateral caudate. Group differences in these regions were specific to rewarding outcomes and did not generalize to neutral or negative outcomes, although relatively reduced responses to monetary penalties in MDD emerged in other caudate regions. By contrast, evidence for group differences during reward anticipation was weaker, although MDD subjects showed reduced activation to reward cues in a small sector of the left posterior putamen. Among MDD subjects, anhedonic symptoms and depression severity were associated with reduced bilateral caudate volume. Conclusions These results indicate that basal ganglia dysfunction in MDD may affect the consummatory phase of reward processing. Additionally, morphometric results suggest that anhedonia in MDD is related to caudate volume. PMID:19411368

  20. Neural substrate expansion for the restoration of brain function

    Directory of Open Access Journals (Sweden)

    Han-Chiao Isaac Chen

    2016-01-01

    Full Text Available Restoring neurological and cognitive function in individuals who have suffered brain damage is one of the principal objectives of modern translational neuroscience. Electrical stimulation approaches, such as deep-brain stimulation, have achieved the most clinical success, but they ultimately may be limited by the computational capacity of the residual cerebral circuitry. An alternative strategy is brain substrate expansion, in which the computational capacity of the brain is augmented through the addition of new processing units and the reconstitution of network connectivity. This latter approach has been explored to some degree using both biological and electronic means but thus far has not demonstrated the ability to reestablish the function of large-scale neuronal networks. In this review, we contend that fulfilling the potential of brain substrate expansion will require a significant shift from current methods that emphasize direct manipulations of the brain (e.g., injections of cellular suspensions and the implantation of multi-electrode arrays to the generation of more sophisticated neural tissues and neural-electric hybrids in vitro that are subsequently transplanted into the brain. Drawing from neural tissue engineering, stem cell biology, and neural interface technologies, this strategy makes greater use of the manifold techniques available in the laboratory to create biocompatible constructs that recapitulate brain architecture and thus are more easily recognized and utilized by brain networks.

  1. DHA effects in brain development and function

    DEFF Research Database (Denmark)

    Lauritzen, Lotte; Brambilla, Paola; Mazzocchi, Allesandra

    2016-01-01

    Docosahexaenoic acid (DHA) is a structural constituent of membranes specifically in the central nervous system. Its accumulation in the fetal brain takes place mainly during the last trimester of pregnancy and continues at very high rates up to the end of the second year of life. Since the endoge...

  2. Hierarchical organization of brain functional network during visual task

    CERN Document Server

    Zhuo, Zhao; Fu, Zhong-Qian; Zhang, Jie

    2011-01-01

    In this paper, the brain functional networks derived from high-resolution synchronous EEG time series during visual task are generated by calculating the phase synchronization among the time series. The hierarchical modular organizations of these networks are systematically investigated by the fast Girvan-Newman algorithm. At the same time, the spatially adjacent electrodes (corresponding to EEG channels) are clustered into functional groups based on anatomical parcellation of brain cortex, and this clustering information are compared to that of the functional network. The results show that the modular architectures of brain functional network are in coincidence with that from the anatomical structures over different levels of hierarchy, which suggests that population of neurons performing the same function excite and inhibit in identical rhythms. The structure-function relationship further reveals that the correlations among EEG time series in the same functional group are much stronger than those in differe...

  3. The Rewards of Learning.

    Science.gov (United States)

    Chance, Paul

    1992-01-01

    Although intrinsic rewards are important, they (along with punishment and encouragement) are insufficient for efficient learning. Teachers must supplement intrinsic rewards with extrinsic rewards, such as praising, complimenting, applauding, and providing other forms of recognition for good work. Teachers should use the weakest reward required to…

  4. Diagnosing Autism Spectrum Disorder through Brain Functional Magnetic Resonance Imaging

    Science.gov (United States)

    2016-03-01

    Diagnosing Autism Spectrum Disorder through Brain Functional Magnetic Resonance Imaging THESIS MARCH 2016 Kyle A. Palko, Second Lieutenant, USAF AFIT...DISORDER THROUGH BRAIN FUNCTIONAL MAGNETIC RESONANCE IMAGING THESIS Presented to the Faculty Department of Operational Sciences Graduate School of...available data includes raw fMRI as well as processed MP RAGE1 images . All data within the ABIDE database was compiled through studies on autism. All

  5. Effects of intravenous glucose on Dopaminergic function in the human brain in vivo

    NARCIS (Netherlands)

    Haltia, Lauri T.; Rinne, Juha O.; Merisaari, Harri; Maguire, Ralph P.; Savontaus, Eriika; Helin, Semi; Nagren, Kjell; Kaasinen, Valtteri

    2007-01-01

    Dopamine is known to regulate food intake by modulating food reward via the mesolimbic circuitry of the brain. The objective of this study was to compare the effects of high energy input (i.v. glucose) on striatal and thalamic dopamine release in overweight and lean individuals. We hypothesized that

  6. The neuroscience of investing: fMRI of the reward system.

    Science.gov (United States)

    Peterson, Richard L

    2005-11-15

    Functional magnetic resonance imaging (fMRI) has proven a useful tool for observing neural BOLD signal changes during complex cognitive and emotional tasks. Yet the meaning and applicability of the fMRI data being gathered is still largely unknown. The brain's reward system underlies the fundamental neural processes of goal evaluation, preference formation, positive motivation, and choice behavior. fMRI technology allows researchers to dynamically visualize reward system processes. Experimenters can then correlate reward system BOLD activations with experimental behavior from carefully controlled experiments. In the SPAN lab at Stanford University, directed by Brian Knutson Ph.D., researchers have been using financial tasks during fMRI scanning to correlate emotion, behavior, and cognition with the reward system's fundamental neural activations. One goal of the SPAN lab is the development of predictive models of behavior. In this paper we extrapolate our fMRI results toward understanding and predicting individual behavior in the uncertain and high-risk environment of the financial markets. The financial market price anomalies of "value versus glamour" and "momentum" may be real-world examples of reward system activation biasing collective behavior. On the individual level, the investor's bias of overconfidence may similarly be related to reward system activation. We attempt to understand selected "irrational" investor behaviors and anomalous financial market price patterns through correlations with findings from fMRI research of the reward system.

  7. Impaired neural reward processing in children and adolescents with reactive attachment disorder: A pilot study.

    Science.gov (United States)

    Mizuno, Kei; Takiguchi, Shinichiro; Yamazaki, Mika; Asano, Mizuki; Kato, Shiho; Kuriyama, Kikuko; Watanabe, Yasuyoshi; Sadato, Norihiro; Tomoda, Akemi

    2015-10-01

    Reactive attachment disorder (RAD) is characterized by markedly disturbed and developmentally inappropriate social relatedness due to parental maltreatment. RAD patients often display a high number of comorbid attention deficit/hyperactivity disorder (ADHD) symptoms, and certain RAD symptoms are difficult to discriminate from ADHD. One of the core characteristics of ADHD is a decrease in neural reward processing due to dopamine dysfunction. The aim of the present study was to determine whether the brain activity involved in reward processing in RAD patients is impaired in comparison with ADHD patients and typically developed controls. Five RAD patients, 17 typically developed (TD) controls and 17 ADHD patients aged 10-16 years performed tasks with high and low monetary reward while undergoing functional magnetic resonance imaging. ADHD patients were tested before and after 3 months treatment with osmotic release oral system-methylphenidate. Before treatment, ADHD patients showed that striatal and thalamus activities only in the tasks with low monetary reward were lower than TD controls. RAD patients showed decrease in activity of the caudate, putamen and thalamus during both the high and low monetary reward conditions in comparison with all the other groups. In RAD patients, the activity of the putamen was associated with the severity of posttraumatic stress and overt dissociation. Reward sensitivity was markedly decreased in children and adolescents with RAD, as evidenced by a diminished neural response during reward perception. This suggests that dopaminergic dysfunction exists in these patients, and may inform future dopaminergic treatment strategies for RAD.

  8. Waiting to win: elevated striatal and orbitofrontal cortical activity during reward anticipation in euthymic bipolar disorder adults

    Science.gov (United States)

    Nusslock, Robin; Almeida, Jorge RC; Forbes, Erika E; Versace, Amelia; Frank, Ellen; LaBarbara, Edmund J; Klein, Crystal R; Phillips, Mary L

    2012-01-01

    Objective Bipolar disorder may be characterized by a hypersensitivity to reward-relevant stimuli, potentially underlying the emotional lability and dysregulation that characterizes the illness. In parallel, research highlights the predominant role of striatal and orbitofrontal cortical (OFC) regions in reward-processing and approach-related affect. We aimed to examine whether bipolar disorder, relative to healthy, participants displayed elevated activity in these regions during reward processing. Methods Twenty-one euthymic bipolar I disorder and 20 healthy control participants with no lifetime history of psychiatric disorder underwent functional magnetic resonance imaging (fMRI) scanning during a card-guessing paradigm designed to examine reward-related brain function to anticipation and receipt of monetary reward and loss. Data were collected using a 3T Siemens Trio scanner. Results Region-of-interest analyses revealed that bipolar disorder participants displayed greater ventral striatal and right-sided orbitofrontal [Brodmann area (BA) 11] activity during anticipation, but not outcome, of monetary reward, relative to healthy controls (p < 0.05, corrected). Wholebrain analyses indicated that bipolar disorder, relative to healthy, participants also displayed elevated left-lateral OFC activity (BA 47) activity during reward anticipation (p < 0.05, corrected). Conclusions Elevated ventral striatal and OFC activity during reward anticipation may represent a neural mechanism for predisposition to expansive mood and hypo/mania in response to reward-relevant cues that characterizes bipolar disorder. Our findings contrast with research reporting blunted activity in the ventral striatum during reward processing in unipolar depressed individuals, relative to healthy controls. Examination of reward-related neural activity in bipolar disorder is a promising research focus to facilitate identification of biological markers of the illness. PMID:22548898

  9. Exploring brain function from anatomical connectivity

    Directory of Open Access Journals (Sweden)

    Gorka eZamora-López

    2011-06-01

    Full Text Available The intrinsic relationship between the architecture of the brain and the range of sensory and behavioral phenomena it produces is a relevant question in neuroscience. Here, we review recent knowledge gained on the architecture of the anatomical connectivity by means of complex network analysis. It has been found that corticocortical networks display a few prominent characteristics: (i modular organization, (ii abundant alternative processing paths and (iii the presence of highly connected hubs. Additionally, we present a novel classification of cortical areas of the cat according to the role they play in multisensory connectivity. All these properties represent an ideal anatomical substrate supporting rich dynamical behaviors, as-well-as facilitating the capacity of the brain to process sensory information of different modalities segregated and to integrate them towards a comprehensive perception of the real world. The result here exposed are mainly based in anatomical data of cats’ brain, but we show how further observations suggest that, from worms to humans, the nervous system of all animals might share fundamental principles of organization.

  10. Dopamine and Reward: The Anhedonia Hypothesis 30 years on

    OpenAIRE

    Wise, Roy A.

    2008-01-01

    The anhedonia hypothesis – that brain dopamine plays a critical role in the subjective pleasure associated with positive rewards – was intended to draw the attention of psychiatrists to the growing evidence that dopamine plays a critical role in the objective reinforcement and incentive motivation associated with food and water, brain stimulation reward, and psychomotor stimulant and opiate reward. The hypothesis called to attention the apparent paradox that neuroleptics, drugs used to treat ...

  11. Violence-related content in video game may lead to functional connectivity changes in brain networks as revealed by fMRI-ICA in young men.

    Science.gov (United States)

    Zvyagintsev, M; Klasen, M; Weber, R; Sarkheil, P; Esposito, F; Mathiak, K A; Schwenzer, M; Mathiak, K

    2016-04-21

    In violent video games, players engage in virtual aggressive behaviors. Exposure to virtual aggressive behavior induces short-term changes in players' behavior. In a previous study, a violence-related version of the racing game "Carmageddon TDR2000" increased aggressive affects, cognitions, and behaviors compared to its non-violence-related version. This study investigates the differences in neural network activity during the playing of both versions of the video game. Functional magnetic resonance imaging (fMRI) recorded ongoing brain activity of 18 young men playing the violence-related and the non-violence-related version of the video game Carmageddon. Image time series were decomposed into functional connectivity (FC) patterns using independent component analysis (ICA) and template-matching yielded a mapping to established functional brain networks. The FC patterns revealed a decrease in connectivity within 6 brain networks during the violence-related compared to the non-violence-related condition: three sensory-motor networks, the reward network, the default mode network (DMN), and the right-lateralized frontoparietal network. Playing violent racing games may change functional brain connectivity, in particular and even after controlling for event frequency, in the reward network and the DMN. These changes may underlie the short-term increase of aggressive affects, cognitions, and behaviors as observed after playing violent video games.

  12. Effects of magnesium sulfate on brain mitochondrial respiratory function in rats after experimental traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    许民辉; 代文光; 邓洵鼎

    2002-01-01

    Objective: To study the effects of magnesium sulfate on brain mitochondrial respiratory function in rats after experimental traumatic brain injury and the possible mechanism.Methods: The middle degree brain injury in rats was made by BIM-III multi-function impacting machine. The brain mitochondrial respiratory function was measured with oxygen electrode and the ultra-structural changes were observed with transmission electron microscope (TEM).Results: 1. The brain mitochondrial respiratory stage III and respiration control rate reduced significantly in the untreated groups within 24 and 72 hours. But treated Group A showed certain degree of recovery of respiratory function; treated Group B showed further improvement. 2. Untreated Group, treated Groups A and B had different degrees of mitochondrial ultra-structural damage respectively, which could be attenuated after the treatment with magnesium sulfate.Conclusions: The mitochondrial respiratory function decreases significantly after traumatic brain injury. But it can be apparently improved after magnesium sulfate management along with the attenuated damage of mitochondria discovered by TEM. The longer course of treatment can obtain a better improvement of mitochondrial respiratory function.

  13. Stress and CRF gate neural activation of BDNF in the mesolimbic reward pathway.

    Science.gov (United States)

    Walsh, Jessica J; Friedman, Allyson K; Sun, Haosheng; Heller, Elizabeth A; Ku, Stacy M; Juarez, Barbara; Burnham, Veronica L; Mazei-Robison, Michelle S; Ferguson, Deveroux; Golden, Sam A; Koo, Ja Wook; Chaudhury, Dipesh; Christoffel, Daniel J; Pomeranz, Lisa; Friedman, Jeffrey M; Russo, Scott J; Nestler, Eric J; Han, Ming-Hu

    2014-01-01

    Mechanisms controlling release of brain-derived neurotrophic factor (BDNF) in the mesolimbic dopamine reward pathway remain unknown. We report that phasic optogenetic activation of this pathway increases BDNF amounts in the nucleus accumbens (NAc) of socially stressed mice but not of stress-naive mice. This stress gating of BDNF signaling is mediated by corticotrophin-releasing factor (CRF) acting in the NAc. These results unravel a stress context-detecting function of the brain's mesolimbic circuit.

  14. Human brain activity with functional NIR optical imager

    Science.gov (United States)

    Luo, Qingming

    2001-08-01

    In this paper we reviewed the applications of functional near infrared optical imager in human brain activity. Optical imaging results of brain activity, including memory for new association, emotional thinking, mental arithmetic, pattern recognition ' where's Waldo?, occipital cortex in visual stimulation, and motor cortex in finger tapping, are demonstrated. It is shown that the NIR optical method opens up new fields of study of the human population, in adults under conditions of simulated or real stress that may have important effects upon functional performance. It makes practical and affordable for large populations the complex technology of measuring brain function. It is portable and low cost. In cognitive tasks subjects could report orally. The temporal resolution could be millisecond or less in theory. NIR method will have good prospects in exploring human brain secret.

  15. EEG-based research on brain functional networks in cognition.

    Science.gov (United States)

    Wang, Niannian; Zhang, Li; Liu, Guozhong

    2015-01-01

    Recently, exploring the cognitive functions of the brain by establishing a network model to understand the working mechanism of the brain has become a popular research topic in the field of neuroscience. In this study, electroencephalography (EEG) was used to collect data from subjects given four different mathematical cognitive tasks: recite numbers clockwise and counter-clockwise, and letters clockwise and counter-clockwise to build a complex brain function network (BFN). By studying the connectivity features and parameters of those brain functional networks, it was found that the average clustering coefficient is much larger than its corresponding random network and the average shortest path length is similar to the corresponding random networks, which clearly shows the characteristics of the small-world network. The brain regions stimulated during the experiment are consistent with traditional cognitive science regarding learning, memory, comprehension, and other rational judgment results. The new method of complex networking involves studying the mathematical cognitive process of reciting, providing an effective research foundation for exploring the relationship between brain cognition and human learning skills and memory. This could help detect memory deficits early in young and mentally handicapped children, and help scientists understand the causes of cognitive brain disorders.

  16. Functional brain connectivity phenotypes for schizophrenia drug discovery.

    Science.gov (United States)

    Dawson, Neil; Morris, Brian J; Pratt, Judith A

    2015-02-01

    While our knowledge of the pathophysiology of schizophrenia has increased dramatically, this has not translated into the development of new and improved drugs to treat this disorder. Human brain imaging and electrophysiological studies have provided dramatic new insight into the mechanisms of brain dysfunction in the disease, with a swathe of recent studies highlighting the differences in functional brain network and neural system connectivity present in the disorder. Only recently has the value of applying these approaches in preclinical rodent models relevant to the disorder started to be recognised. Here we highlight recent findings of altered functional brain connectivity in preclinical rodent models and consider their relevance to those alterations seen in the brains of schizophrenia patients. Furthermore, we highlight the potential translational value of using the paradigm of functional brain connectivity phenotypes in the context of preclinical schizophrenia drug discovery, as a means both to understand the mechanisms of brain dysfunction in the disorder and to reduce the current high attrition rate in schizophrenia drug discovery.

  17. [Determinism and Freedom of Choice in the Brain Functioning].

    Science.gov (United States)

    Ivanitsky, A M

    2015-01-01

    The problem is considered whether the brain response is completely determined by the stimulus and the personal experience or in some cases the brain is free to choose its behavioral response to achieve the desired goal. The attempt is made to approach to this important philosophical problem basing on modern knowledge about the brain. The paper consists of four parts. In the first part the theoretical views about the free choice problem solving are considered, including views about the freedom of choice as a useful illusion, the hypothesis on appliance of quantum mechanics laws to the brain functioning and the theory of mentalism. In other tree parts consequently the more complicated brain functions such as choice reaction, thinking and creation are analyzed. The general conclusion is that the possibility of quite unpredictable, but sometimes very effective decisions increases when the brain functions are more and more complicated. This fact can be explained with two factors: increasing stochasticity of the brain processes and the role of top-down determinations from mental to neural levels, according to the theory of mentalism.

  18. Additive effects of oxytocin receptor gene polymorphisms on reward circuitry in youth with autism.

    Science.gov (United States)

    Hernandez, L M; Krasileva, K; Green, S A; Sherman, L E; Ponting, C; McCarron, R; Lowe, J K; Geschwind, D H; Bookheimer, S Y; Dapretto, M

    2016-11-15

    Several common alleles in the oxytocin receptor gene (OXTR) are associated with altered brain function in reward circuitry in neurotypical adults and may increase risk for autism spectrum disorders (ASD). Yet, it is currently unknown how variation in the OXTR relates to brain functioning in individuals with ASD, and, critically, whether neural endophenotypes vary as a function of aggregate genetic risk. Here, for we believe the first time, we use a multi-locus approach to examine how genetic variation across several OXTR single-nucleotide polymorphisms (SNPs) affect functional connectivity of the brain's reward network. Using data from 41 children with ASD and 41 neurotypical children, we examined functional connectivity of the nucleus accumbens (NAcc) - a hub of the reward network - focusing on how connectivity varies with OXTR risk-allele dosage. Youth with ASD showed reduced NAcc connectivity with other areas in the reward circuit as a function of increased OXTR risk-allele dosage, as well as a positive association between risk-allele dosage and symptom severity, whereas neurotypical youth showed increased NAcc connectivity with frontal brain regions involved in mentalizing. In addition, we found that increased NAcc-frontal cortex connectivity in typically developing youth was related to better scores on a standardized measure of social functioning. Our results indicate that cumulative genetic variation on the OXTR impacts reward system connectivity in both youth with ASD and neurotypical controls. By showing differential genetic effects on neuroendophenotypes, these pathways elucidate mechanisms of vulnerability versus resilience in carriers of disease-associated risk alleles.Molecular Psychiatry advance online publication, 15 November 2016; doi:10.1038/mp.2016.209.

  19. Led into temptation? Rewarding brand logos bias the neural encoding of incidental economic decisions.

    Science.gov (United States)

    Murawski, Carsten; Harris, Philip G; Bode, Stefan; Domínguez D, Juan F; Egan, Gary F

    2012-01-01

    Human decision-making is driven by subjective values assigned to alternative choice options. These valuations are based on reward cues. It is unknown, however, whether complex reward cues, such as brand logos, may bias the neural encoding of subjective value in unrelated decisions. In this functional magnetic resonance imaging (fMRI) study, we subliminally presented brand logos preceding intertemporal choices. We demonstrated that priming biased participants' preferences towards more immediate rewards in the subsequent temporal discounting task. This was associated with modulations of the neural encoding of subjective values of choice options in a network of brain regions, including but not restricted to medial prefrontal cortex. Our findings demonstrate the general susceptibility of the human decision making system to apparently incidental contextual information. We conclude that the brain incorporates seemingly unrelated value information that modifies decision making outside the decision-maker's awareness.

  20. Led into temptation? Rewarding brand logos bias the neural encoding of incidental economic decisions.

    Directory of Open Access Journals (Sweden)

    Carsten Murawski

    Full Text Available Human decision-making is driven by subjective values assigned to alternative choice options. These valuations are based on reward cues. It is unknown, however, whether complex reward cues, such as brand logos, may bias the neural encoding of subjective value in unrelated decisions. In this functional magnetic resonance imaging (fMRI study, we subliminally presented brand logos preceding intertemporal choices. We demonstrated that priming biased participants' preferences towards more immediate rewards in the subsequent temporal discounting task. This was associated with modulations of the neural encoding of subjective values of choice options in a network of brain regions, including but not restricted to medial prefrontal cortex. Our findings demonstrate the general susceptibility of the human decision making system to apparently incidental contextual information. We conclude that the brain incorporates seemingly unrelated value information that modifies decision making outside the decision-maker's awareness.

  1. Brain-Computer Interface Controlled Cyborg: Establishing a Functional Information Transfer Pathway from Human Brain to Cockroach Brain.

    Science.gov (United States)

    Li, Guangye; Zhang, Dingguo

    2016-01-01

    An all-chain-wireless brain-to-brain system (BTBS), which enabled motion control of a cyborg cockroach via human brain, was developed in this work. Steady-state visual evoked potential (SSVEP) based brain-computer interface (BCI) was used in this system for recognizing human motion intention and an optimization algorithm was proposed in SSVEP to improve online performance of the BCI. The cyborg cockroach was developed by surgically integrating a portable microstimulator that could generate invasive electrical nerve stimulation. Through Bluetooth communication, specific electrical pulse trains could be triggered from the microstimulator by BCI commands and were sent through the antenna nerve to stimulate the brain of cockroach. Serial experiments were designed and conducted to test overall performance of the BTBS with six human subjects and three cockroaches. The experimental results showed that the online classification accuracy of three-mode BCI increased from 72.86% to 78.56% by 5.70% using the optimization algorithm and the mean response accuracy of the cyborgs using this system reached 89.5%. Moreover, the results also showed that the cyborg could be navigated by the human brain to complete walking along an S-shape track with the success rate of about 20%, suggesting the proposed BTBS established a feasible functional information transfer pathway from the human brain to the cockroach brain.

  2. Reward: From Basic Reinforcers to Anticipation of Social Cues.

    Science.gov (United States)

    Rademacher, Lena; Schulte-Rüther, Martin; Hanewald, Bernd; Lammertz, Sarah

    2017-01-01

    Reward processing plays a major role in goal-directed behavior and motivation. On the neural level, it is mediated by a complex network of brain structures called the dopaminergic reward system. In the last decade, neuroscientific researchers have become increasingly interested in aspects of social interaction that are experienced as rewarding. Recent neuroimaging studies have provided evidence that the reward system mediates the processing of social stimuli in a manner analogous to nonsocial rewards and thus motivates social behavior. In this context, the neuropeptide oxytocin is assumed to play a key role by activating dopaminergic reward pathways in response to social cues, inducing the rewarding quality of social interactions. Alterations in the dopaminergic reward system have been found in several psychiatric disorders that are accompanied by social interaction and motivation problems, for example autism, attention deficit/hyperactivity disorder, addiction disorders, and schizophrenia.

  3. Effect of glycolysis inhibition on mitochondrial function in rat brain.

    Science.gov (United States)

    Cano-Ramírez, D; Torres-Vargas, C E; Guerrero-Castillo, S; Uribe-Carvajal, S; Hernández-Pando, R; Pedraza-Chaverri, J; Orozco-Ibarra, M

    2012-05-01

    Inhibition of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase enhances the neural vulnerability to excitotoxicity both in vivo and in vitro through an unknown mechanism possibly related to mitochondrial failure. However, as the effect of glycolysis inhibition on mitochondrial function in brain has not been studied, the aim of the present work was to evaluate the effect of glycolysis inhibition induced by iodoacetate on mitochondrial function and oxidative stress in brain. Mitochondria were isolated from brain cortex, striatum and cerebellum of rats treated systemically with iodoacetate (25 mg/kg/day for 3 days). Oxygen consumption, ATP synthesis, transmembrane potential, reactive oxygen species production, lipoperoxidation, glutathione levels, and aconitase activity were assessed. Oxygen consumption and aconitase activity decreased in the brain cortex and striatum, showing that glycolysis inhibition did not trigger severe mitochondrial impairment, but a slight mitochondrial malfunction and oxidative stress were present.

  4. Model of local temperature changes in brain upon functional activation.

    Science.gov (United States)

    Collins, Christopher M; Smith, Michael B; Turner, Robert

    2004-12-01

    Experimental results for changes in brain temperature during functional activation show large variations. It is, therefore, desirable to develop a careful numerical model for such changes. Here, a three-dimensional model of temperature in the human head using the bioheat equation, which includes effects of metabolism, perfusion, and thermal conduction, is employed to examine potential temperature changes due to functional activation in brain. It is found that, depending on location in brain and corresponding baseline temperature relative to blood temperature, temperature may increase or decrease on activation and concomitant increases in perfusion and rate of metabolism. Changes in perfusion are generally seen to have a greater effect on temperature than are changes in metabolism, and hence active brain is predicted to approach blood temperature from its initial temperature. All calculated changes in temperature for reasonable physiological parameters have magnitudes <0.12 degrees C and are well within the range reported in recent experimental studies involving human subjects.

  5. [Functional imaging of deep brain stimulation in idiopathic Parkinson's disease].

    Science.gov (United States)

    Hilker, R

    2010-10-01

    Functional brain imaging allows the effects of deep brain stimulation (DBS) on the living human brain to be investigated. In patients with advanced Parkinson's disease (PD), positron emission tomography (PET) studies were undertaken at rest as well as under motor, cognitive or behavioral activation. DBS leads to a reduction of abnormal PD-related network activity in the motor system, which partly correlates with the improvement of motor symptoms. The local increase of energy consumption within the direct target area suggests a predominant excitatory influence of the stimulation current on neuronal tissue. Remote effects of DBS of the subthalamic nucleus (STN) on frontal association cortices indicate an interference of stimulation energy with associative and limbic basal ganglia loops. Taken together, functional brain imaging provides very valuable data for advancement of the DBS technique in PD therapy.

  6. A simple solution for model comparison in bold imaging: the special case of reward prediction error and reward outcomes.

    Science.gov (United States)

    Erdeniz, Burak; Rohe, Tim; Done, John; Seidler, Rachael D

    2013-01-01

    Conventional neuroimaging techniques provide information about condition-related changes of the BOLD (blood-oxygen-level dependent) signal, indicating only where and when the underlying cognitive processes occur. Recently, with the help of a new approach called "model-based" functional neuroimaging (fMRI), researchers are able to visualize changes in the internal variables of a time varying learning process, such as the reward prediction error or the predicted reward value of a conditional stimulus. However, despite being extremely beneficial to the imaging community in understanding the neural correlates of decision variables, a model-based approach to brain imaging data is also methodologically challenging due to the multicollinearity problem in statistical analysis. There are multiple sources of multicollinearity in functional neuroimaging including investigations of closely related variables and/or experimental designs that do not account for this. The source of multicollinearity discussed in this paper occurs due to correlation between different subjective variables that are calculated very close in time. Here, we review methodological approaches to analyzing such data by discussing the special case of separating the reward prediction error signal from reward outcomes.

  7. Developing brain vital signs: Initial framework for monitoring brain function changes over time

    Directory of Open Access Journals (Sweden)

    Sujoy eGhosh Hajra

    2016-05-01

    Full Text Available Clinical assessment of brain function relies heavily on indirect behavior-based tests. Unfortunately, behavior-based assessments are subjective and therefore susceptible to several confounding factors. Event-related brain potentials (ERPs, derived from electroencephalography (EEG, are often used to provide objective, physiological measures of brain function. Historically, ERPs have been characterized extensively within research settings, with limited but growing clinical applications. Over the past 20 years, we have developed clinical ERP applications for the evaluation of functional status following serious injury and/or disease. This work has identified an important gap: the need for a clinically accessible framework to evaluate ERP measures. Crucially, this enables baseline measures before brain dysfunction occurs, and might enable the routine collection of brain function metrics in the future much like blood pressure measures today. Here, we propose such a framework for extracting specific ERPs as potential brain vital signs. This framework enabled the translation/transformation of complex ERP data into accessible metrics of brain function for wider clinical utilization. To formalize the framework, three essential ERPs were selected as initial indicators: 1 the auditory N100 (Auditory sensation; 2 the auditory oddball P300 (Basic attention; and 3 the auditory speech processing N400 (Cognitive processing. First step validation was conducted on healthy younger and older adults (age range: 22-82 years. Results confirmed specific ERPs at the individual level (86.81%-98.96%, verified predictable age-related differences (P300 latency delays in older adults, p<0.05, and demonstrated successful linear transformation into the proposed brain vital sign (BVS framework (basic attention latency sub-component of BVS framework reflects delays in older adults, p<0.05. The findings represent an initial critical step in developing, extracting, and

  8. Functional and dysfunctional brain circuits underlying emotional processing of music in autism spectrum disorders.

    Science.gov (United States)

    Caria, Andrea; Venuti, Paola; de Falco, Simona

    2011-12-01

    Despite intersubject variability, dramatic impairments of socio-communicative skills are core features of autistic spectrum disorder (ASD). A deficit in the ability to express and understand emotions has often been hypothesized to be an important correlate of such impairments. Little is known about individuals with ASD's ability to sense emotions conveyed by nonsocial stimuli such as music. Music has been found to be capable of evoking and conveying strong and consistent positive and negative emotions in healthy subjects. The ability to process perceptual and emotional aspects of music seems to be maintained in ASD. Individuals with ASD and neurotypical (NT) controls underwent a single functional magnetic resonance imaging (fMRI) session while processing happy and sad music excerpts. Overall, fMRI results indicated that while listening to both happy and sad music, individuals with ASD activated cortical and subcortical brain regions known to be involved in emotion processing and reward. A comparison of ASD participants with NT individuals demonstrated decreased brain activity in the premotor area and in the left anterior insula, especially in response to happy music excerpts. Our findings shed new light on the neurobiological correlates of preserved and altered emotional processing in ASD.

  9. Joint brain connectivity estimation from diffusion and functional MRI data

    Science.gov (United States)

    Chu, Shu-Hsien; Lenglet, Christophe; Parhi, Keshab K.

    2015-03-01

    Estimating brain wiring patterns is critical to better understand the brain organization and function. Anatomical brain connectivity models axonal pathways, while the functional brain connectivity characterizes the statistical dependencies and correlation between the activities of various brain regions. The synchronization of brain activity can be inferred through the variation of blood-oxygen-level dependent (BOLD) signal from functional MRI (fMRI) and the neural connections can be estimated using tractography from diffusion MRI (dMRI). Functional connections between brain regions are supported by anatomical connections, and the synchronization of brain activities arises through sharing of information in the form of electro-chemical signals on axon pathways. Jointly modeling fMRI and dMRI data may improve the accuracy in constructing anatomical connectivity as well as functional connectivity. Such an approach may lead to novel multimodal biomarkers potentially able to better capture functional and anatomical connectivity variations. We present a novel brain network model which jointly models the dMRI and fMRI data to improve the anatomical connectivity estimation and extract the anatomical subnetworks associated with specific functional modes by constraining the anatomical connections as structural supports to the functional connections. The key idea is similar to a multi-commodity flow optimization problem that minimizes the cost or maximizes the efficiency for flow configuration and simultaneously fulfills the supply-demand constraint for each commodity. In the proposed network, the nodes represent the grey matter (GM) regions providing brain functionality, and the links represent white matter (WM) fiber bundles connecting those regions and delivering information. The commodities can be thought of as the information corresponding to brain activity patterns as obtained for instance by independent component analysis (ICA) of fMRI data. The concept of information

  10. Transcranial brain stimulation to promote functional recovery after stroke

    DEFF Research Database (Denmark)

    Raffin, Estelle; Siebner, Hartwig R

    2014-01-01

    PURPOSE OF REVIEW: Noninvasive brain stimulation (NIBS) is increasingly used to enhance the recovery of function after stroke. The purpose of this review is to highlight and discuss some unresolved questions that need to be addressed to better understand and exploit the potential of NIBS...... therapeutic efficacy. SUMMARY: This review addressed six questions: How does NIBS facilitate the recovery of function after stroke? Which brain regions should be targeted by NIBS? Is there a particularly effective NIBS modality that should be used? Does the location of the stroke influence the therapeutic...... response? How often should NIBS be repeated? Is the functional state of the brain during or before NIBS relevant to therapeutic efficacy of NIBS? We argue that these questions need to be tackled to obtain sufficient mechanistic understanding of how NIBS facilitates the recovery of function. This knowledge...

  11. Joint Modelling of Structural and Functional Brain Networks

    DEFF Research Database (Denmark)

    Andersen, Kasper Winther; Herlau, Tue; Mørup, Morten

    Functional and structural magnetic resonance imaging have become the most important noninvasive windows to the human brain. A major challenge in the analysis of brain networks is to establish the similarities and dissimilarities between functional and structural connectivity. We formulate a non...... significant structures that are consistently shared across subjects and data splits. This provides an unsupervised approach for modeling of structure-function relations in the brain and provides a general framework for multimodal integration.......-parametric Bayesian network model which allows for joint modelling and integration of multiple networks. We demonstrate the model’s ability to detect vertices that share structure across networks jointly in functional MRI (fMRI) and diffusion MRI (dMRI) data. Using two fMRI and dMRI scans per subject, we establish...

  12. Early Bifrontal Brain Injury: Disturbances in Cognitive Function Development

    Directory of Open Access Journals (Sweden)

    Christine Bonnier

    2010-01-01

    Full Text Available We describe six psychomotor, language, and neuropsychological sequential developmental evaluations in a boy who sustained a severe bifrontal traumatic brain injury (TBI at 19 months of age. Visuospatial, drawing, and writing skills failed to develop normally. Gradually increasing difficulties were noted in language leading to reading and spontaneous speech difficulties. The last two evaluations showed executive deficits in inhibition, flexibility, and working memory. Those executive abnormalities seemed to be involved in the other impairments. In conclusion, early frontal brain injury disorganizes the development of cognitive functions, and interactions exist between executive function and other cognitive functions during development.

  13. Dopamine and glucose, obesity and Reward Deficiency Syndrome

    Directory of Open Access Journals (Sweden)

    Kenneth eBlum

    2014-09-01

    Full Text Available Obesity and many well described eating disorders are accurately considered a global epidemic. The consequences of Reward Deficiency Syndrome, a genetic and epigenetic phenomena that involves the interactions of powerful neurotransmitters, are impairments of brain reward circuitry, hypodopaminergic function and abnormal craving behavior. Numerous sound neurochemical and genetic studies provide strong evidence that food addiction is similar to psychoactive drug addiction. Important facts which could translate to potential therapeutic targets espoused in this review include: 1 brain dopamine (DA production and use is stimulated by consumption of alcohol in large quantities or carbohydrates bingeing; 2 in the mesolimbic system the enkephalinergic neurons are in close proximity, to glucose receptors; 3 highly concentrated glucose activates the calcium channel to stimulate dopamine release from P12 cells; 4 blood glucose and cerebrospinal fluid concentrations of homovanillic acid, the dopamine metabolite, are significantly correlated and 5 2-deoxyglucose the glucose analogue, in pharmacological doses associates with enhanced dopamine turnover and causes acute glucoprivation. Evidence from animal studies and human fMRI support the hypothesis that multiple, but similar brain circuits are disrupted in obesity and drug dependence and DA-modulated reward circuits are involved in pathologic eating behaviors. Treatment for addiction to glucose and drugs alike, based on a consensus of neuroscience research, should incorporate dopamine agonist therapy, in contrast to current theories and practices that use dopamine antagonists. Until now, powerful dopamine-D2 agonists have failed clinically, due to chronic down regulation of D2 receptors instead, consideration of novel less powerful D2 agonists that up-regulate D2 receptors seems prudent. We encourage new strategies targeted at improving DA function in the treatment and prevention of obesity a subtype of

  14. The reward of a good joke: neural correlates of viewing dynamic displays of stand-up comedy.

    Science.gov (United States)

    Franklin, Robert G; Adams, Reginald B

    2011-12-01

    Humor is enjoyable, yet few studies to date have reported that humor engages brain regions involved in reward processing (i.e., the mesolimbic reward system). Even fewer have investigated socially relevant, dynamic displays of real actors telling jokes. Instead, many studies have focused on responses to static cartoons or written jokes in isolation. In the present investigation, we used functional magnetic resonance imaging (fMRI) to examine brain activation in response to video clips of comedians performing stand-up comedy, a more socially relevant task than reading jokes or cartoons in isolation. Participants watched video clips of eight stand-up comedians, half female/half male, that were prerated by a separate group of participants from the same population as eliciting either high or low levels of amusement, thereby allowing us to control for comedian attributes and comedic style. We found that high-funny clips elicited more activation in several brain regions involved with reward responses, including the nucleus accumbens, caudate, and putamen. A regression with participants' own ratings of humor revealed similar activity in reward areas as well as in regions involved in theory of mind. These findings indicate that dynamic social displays of humor do engage reward responses. The rewarding nature of humor may help explain why it is so valued socially.

  15. The Role of Brain Aging in Cognition and Motor Function

    NARCIS (Netherlands)

    Y.Y. Hoogendam (Jory)

    2014-01-01

    markdownabstract__Abstract__ Aging of the population is accompanied by many challenges, such as the maintenance of health and quality of life during older age. An important aspect of living longer is that old age is related to disease and loss of functions. The loss of brain functions poses a large

  16. Is performance better when brain functions are typically lateralized?

    NARCIS (Netherlands)

    Geuze, Reint; Zickert, Nele; Beking, Tess; Groothuis, Antonius

    2014-01-01

    Lateralization refers to the dominant involvement of one homologous region of the brain over the other in functional task performance. Direction and strength of lateralization depend on the functional task. It is well known that language is lateralized to the left hemisphere, even in most left-hande

  17. Clinimetrics and functional outcome one year after traumatic brain injury

    NARCIS (Netherlands)

    J.T.M. van Baalen (Bianca)

    2008-01-01

    textabstractThis thesis is based on the findings of the FuPro-TBI (Functional Prognosis in Traumatic Brain Injury) study, which was part of the national FuPro research programme which investigated the functional prognosis of four neurological disorders: multiple sclerosis (MS), stroke, amyotrofic l

  18. Mapping Human Brain Function with MRI at 7 Tesla

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ In the past decade, the most significant development in MRI is the introduction of fMRI, which permits the mapping of human brain function with exquisite details noninvasively. Functional mapping can be achieved by measuring changes in the blood oxygenation level (I.e. The BOLD contrast) or cerebral blood flow.

  19. The brain and development of function

    NARCIS (Netherlands)

    Touwen, BCL

    1998-01-01

    Neurobiological and functional development are discontinuous. The interrelationships between identifiable morphological processes and the developmental course of functional display are astonishingly weak. One of the first persons who tried to find a solution for this problem was McGraw. This paper t

  20. Data mining a functional neuroimaging database for functional segregation in brain regions

    DEFF Research Database (Denmark)

    Nielsen, Finn Årup; Balslev, Daniela; Hansen, Lars Kai

    2006-01-01

    We describe a specialized neuroinformatic data mining technique in connection with a meta-analytic functional neuroimaging database: We mine for functional segregation within brain regions by identifying journal articles that report brain activations within the regions and clustering the abstract...

  1. Adaptation of brain functional and structural networks in aging.

    Science.gov (United States)

    Lee, Annie; Ratnarajah, Nagulan; Tuan, Ta Anh; Chen, Shen-Hsing Annabel; Qiu, Anqi

    2015-01-01

    The human brain, especially the prefrontal cortex (PFC), is functionally and anatomically reorganized in order to adapt to neuronal challenges in aging. This study employed structural MRI, resting-state fMRI (rs-fMRI), and high angular resolution diffusion imaging (HARDI), and examined the functional and structural reorganization of the PFC in aging using a Chinese sample of 173 subjects aged from 21 years and above. We found age-related increases in the structural connectivity between the PFC and posterior brain regions. Such findings were partially mediated by age-related increases in the structural connectivity of the occipital lobe within the posterior brain. Based on our findings, it is thought that the PFC reorganization in aging could be partly due to the adaptation to age-related changes in the structural reorganization of the posterior brain. This thus supports the idea derived from task-based fMRI that the PFC reorganization in aging may be adapted to the need of compensation for resolving less distinctive stimulus information from the posterior brain regions. In addition, we found that the structural connectivity of the PFC with the temporal lobe was fully mediated by the temporal cortical thickness, suggesting that the brain morphology plays an important role in the functional and structural reorganization with aging.

  2. Resting-state brain organization revealed by functional covariance networks.

    Directory of Open Access Journals (Sweden)

    Zhiqiang Zhang

    Full Text Available BACKGROUND: Brain network studies using techniques of intrinsic connectivity network based on fMRI time series (TS-ICN and structural covariance network (SCN have mapped out functional and structural organization of human brain at respective time scales. However, there lacks a meso-time-scale network to bridge the ICN and SCN and get insights of brain functional organization. METHODOLOGY AND PRINCIPAL FINDINGS: We proposed a functional covariance network (FCN method by measuring the covariance of amplitude of low-frequency fluctuations (ALFF in BOLD signals across subjects, and compared the patterns of ALFF-FCNs with the TS-ICNs and SCNs by mapping the brain networks of default network, task-positive network and sensory networks. We demonstrated large overlap among FCNs, ICNs and SCNs and modular nature in FCNs and ICNs by using conjunctional analysis. Most interestingly, FCN analysis showed a network dichotomy consisting of anti-correlated high-level cognitive system and low-level perceptive system, which is a novel finding different from the ICN dichotomy consisting of the default-mode network and the task-positive network. CONCLUSION: The current study proposed an ALFF-FCN approach to measure the interregional correlation of brain activity responding to short periods of state, and revealed novel organization patterns of resting-state brain activity from an intermediate time scale.

  3. Adaptation of brain functional and structural networks in aging.

    Directory of Open Access Journals (Sweden)

    Annie Lee

    Full Text Available The human brain, especially the prefrontal cortex (PFC, is functionally and anatomically reorganized in order to adapt to neuronal challenges in aging. This study employed structural MRI, resting-state fMRI (rs-fMRI, and high angular resolution diffusion imaging (HARDI, and examined the functional and structural reorganization of the PFC in aging using a Chinese sample of 173 subjects aged from 21 years and above. We found age-related increases in the structural connectivity between the PFC and posterior brain regions. Such findings were partially mediated by age-related increases in the structural connectivity of the occipital lobe within the posterior brain. Based on our findings, it is thought that the PFC reorganization in aging could be partly due to the adaptation to age-related changes in the structural reorganization of the posterior brain. This thus supports the idea derived from task-based fMRI that the PFC reorganization in aging may be adapted to the need of compensation for resolving less distinctive stimulus information from the posterior brain regions. In addition, we found that the structural connectivity of the PFC with the temporal lobe was fully mediated by the temporal cortical thickness, suggesting that the brain morphology plays an important role in the functional and structural reorganization with aging.

  4. Functional Connectivity Hubs and Networks in the Awake Marmoset Brain

    Directory of Open Access Journals (Sweden)

    Annabelle Marie Belcher

    2016-03-01

    Full Text Available In combination with advances in analytical methods, resting-state fMRI is allowing unprecedented access to achieve a better understanding of the network organization of the brain. Increasing evidence suggests that this architecture may incorporate highly functionally connected nodes, or hubs, and we have recently proposed local functional connectivity density (lFCD mapping to identify highly-connected nodes in the human brain. Here we imaged awake nonhuman primates to test whether, like the human brain, the marmoset brain contains functional connectivity hubs. Ten adult common marmosets (Callithrix jacchus were acclimated to mild, comfortable restraint using individualized helmets. Following restraint training, resting BOLD data were acquired during eight consecutive 10 min scans for each subject. lFCD revealed prominent cortical and subcortical hubs of connectivity across the marmoset brain; specifically, in primary and secondary visual cortices (V1/V2, higher-order visual association areas (A19M/V6[DM], posterior parietal and posterior cingulate areas (PGM and A23b/A31, thalamus, dorsal and ventral striatal areas (caudate, putamen, lateral septal nucleus, and anterior cingulate cortex (A24a. lFCD hubs were highly connected to widespread areas of the brain, and further revealed significant network-network interactions. These data provide a baseline platform for future investigations in a nonhuman primate model of the brain’s network topology.

  5. Endocannabinoid signalling in reward and addiction.

    Science.gov (United States)

    Parsons, Loren H; Hurd, Yasmin L

    2015-10-01

    Brain endocannabinoid (eCB) signalling influences the motivation for natural rewards (such as palatable food, sexual activity and social interaction) and modulates the rewarding effects of addictive drugs. Pathological forms of natural and drug-induced reward are associated with dysregulated eCB signalling that may derive from pre-existing genetic factors or from prolonged drug exposure. Impaired eCB signalling contributes to dysregulated synaptic plasticity, increased stress responsivity, negative emotional states and cravings that propel addiction. Understanding the contributions of eCB disruptions to behavioural and physiological traits provides insight into the eCB influence on addiction vulnerability.

  6. Understanding entangled cerebral networks: A prerequisite for restoring brain function with brain-computer interfaces

    Directory of Open Access Journals (Sweden)

    Emmanuel eMandonnet

    2014-05-01

    Full Text Available Historically, cerebral processing has been conceptualized as a framework based on statically localized functions. However, a growing amount of evidence supports a hodotopical (delocalized and flexible organization. A number of studies have reported absence of a permanent neurological deficit after massive surgical resections of eloquent brain tissue. These results highlight the tremendous plastic potential of the brain. Understanding anatomo-functional correlates underlying this cerebral reorganization is a prerequisite to restore brain functions through brain-computer interfaces (BCIs in patients with cerebral diseases, or even to potentiate brain functions in healthy individuals. Here, we review current knowledge of neural networks that could be utilized in the BCIs that enable movements and language. To this end, intraoperative electrical stimulation in awake patients provides valuable information on the cerebral functional maps, their connectomics and plasticity. Overall, these studies indicate that the complex cerebral circuitry that underpins interactions between action, cognition and behavior should be throughly investigated before progress in BCI approaches can be achieved.

  7. Decreased functional brain connectivity in adolescents with internet addiction.

    Directory of Open Access Journals (Sweden)

    Soon-Beom Hong

    Full Text Available BACKGROUND: Internet addiction has become increasingly recognized as a mental disorder, though its neurobiological basis is unknown. This study used functional neuroimaging to investigate whole-brain functional connectivity in adolescents diagnosed with internet addiction. Based on neurobiological changes seen in other addiction related disorders, it was predicted that connectivity disruptions in adolescents with internet addiction would be most prominent in cortico-striatal circuitry. METHODS: Participants were 12 adolescents diagnosed with internet addiction and 11 healthy comparison subjects. Resting-state functional magnetic resonance images were acquired, and group differences in brain functional connectivity were analyzed using the network-based statistic. We also analyzed network topology, testing for between-group differences in key graph-based network measures. RESULTS: Adolescents with internet addiction showed reduced functional connectivity spanning a distributed network. The majority of impaired connections involved cortico-subcortical circuits (∼24% with prefrontal and ∼27% with parietal cortex. Bilateral putamen was the most extensively involved subcortical brain region. No between-group difference was observed in network topological measures, including the clustering coefficient, characteristic path length, or the small-worldness ratio. CONCLUSIONS: Internet addiction is associated with a widespread and significant decrease of functional connectivity in cortico-striatal circuits, in the absence of global changes in brain functional network topology.

  8. [Endocrine functions of the brain in adult and developing mammals].

    Science.gov (United States)

    Ugriumov, M V

    2009-01-01

    The main prerequisite for organism's viability is the maintenance of the internal environment despite changes in the external environment, which is provided by the neuroendocrine control system. The key unit in this system is hypothalamus exerting endocrine effects on certain peripheral organs and anterior pituitary. Physiologically active substances of neuronal origin enter blood vessels in the neurohemal parts of hypothalamus where no blood-brain barrier exists. In other parts of the adult brain, the arrival of physiologically active substances is blocked by the blood-brain barrier. According to the generally accepted concept, the neuroendocrine system formation in ontogeny starts with the maturation of peripheral endocrine glands, which initially function autonomously and then are controlled by the anterior pituitary. The brain is engaged in neuroendocrine control after its maturation completes, which results in a closed control system typical of adult mammals. Since neurons start to secrete physiologically active substances soon after their formation and long before interneuronal connections are formed, these cells are thought to have an effect on brain development as inducers. Considering that there is no blood-brain barrier during this period, we proposed the hypothesis that the developing brain functions as a multipotent endocrine organ. This means that tens of physiologically active substances arrive from the brain to the systemic circulation and have an endocrine effect on the whole body development. Dopamine, serotonin, and gonadotropin-releasing hormone were selected as marker physiologically active substances of cerebral origin to test this hypothesis. In adult animals, they act as neurotransmitters or neuromodulators transmitting information from neuron to neuron as well as neurohormones arriving from the hypothalamus with portal blood to the anterior pituitary. Perinatal rats--before the blood-brain barrier is formed--proved to have equally high

  9. Assortative mixing in functional brain networks during epileptic seizures

    CERN Document Server

    Bialonski, Stephan

    2013-01-01

    We investigate assortativity of functional brain networks before, during, and after one-hundred epileptic seizures with different anatomical onset locations. We construct binary functional networks from multi-channel electroencephalographic data recorded from 60 epilepsy patients, and from time-resolved estimates of the assortativity coefficient we conclude that positive degree-degree correlations are inherent to seizure dynamics. While seizures evolve, an increasing assortativity indicates a segregation of the underlying functional network into groups of brain regions that are only sparsely interconnected, if at all. Interestingly, assortativity decreases already prior to seizure end. Together with previous observations of characteristic temporal evolutions of global statistical properties and synchronizability of epileptic brain networks, our findings may help to gain deeper insights into the complicated dynamics underlying generation, propagation, and termination of seizures.

  10. Totally Tubular: The Mystery behind Function and Origin of the Brain Ventricular System

    OpenAIRE

    Lowery, Laura Anne; Sive, Hazel

    2009-01-01

    A unique feature of the vertebrate brain is the brain ventricular system, a series of connected cavities which are filled with cerebrospinal fluid (CSF) and surrounded by neuroepithelium. While CSF is critical for both adult brain function and embryonic brain development, neither development nor function of the brain ventricular system is fully understood. In this review, we discuss the mystery of why vertebrate brains have ventricles, and whence they originate. The brain ventricular system d...

  11. Hemispheric asymmetry of electroencephalography-based functional brain networks.

    Science.gov (United States)

    Jalili, Mahdi

    2014-11-12

    Electroencephalography (EEG)-based functional brain networks have been investigated frequently in health and disease. It has been shown that a number of graph theory metrics are disrupted in brain disorders. EEG-based brain networks are often studied in the whole-brain framework, where all the nodes are grouped into a single network. In this study, we studied the brain networks in two hemispheres and assessed whether there are any hemispheric-specific patterns in the properties of the networks. To this end, resting state closed-eyes EEGs from 44 healthy individuals were processed and the network structures were extracted separately for each hemisphere. We examined neurophysiologically meaningful graph theory metrics: global and local efficiency measures. The global efficiency did not show any hemispheric asymmetry, whereas the local connectivity showed rightward asymmetry for a range of intermediate density values for the constructed networks. Furthermore, the age of the participants showed significant direct correlations with the global efficiency of the left hemisphere, but only in the right hemisphere, with local connectivity. These results suggest that only local connectivity of EEG-based functional networks is associated with brain hemispheres.

  12. Reduction of brain kynurenic acid improves cognitive function.

    Science.gov (United States)

    Kozak, Rouba; Campbell, Brian M; Strick, Christine A; Horner, Weldon; Hoffmann, William E; Kiss, Tamas; Chapin, Douglas S; McGinnis, Dina; Abbott, Amanda L; Roberts, Brooke M; Fonseca, Kari; Guanowsky, Victor; Young, Damon A; Seymour, Patricia A; Dounay, Amy; Hajos, Mihaly; Williams, Graham V; Castner, Stacy A

    2014-08-06

    The elevation of kynurenic acid (KYNA) observed in schizophrenic patients may contribute to core symptoms arising from glutamate hypofunction, including cognitive impairments. Although increased KYNA levels reduce excitatory neurotransmission, KYNA has been proposed to act as an endogenous antagonist at the glycine site of the glutamate NMDA receptor (NMDAR) and as a negative allosteric modulator at the α7 nicotinic acetylcholine receptor. Levels of KYNA are elevated in CSF and the postmortem brain of schizophrenia patients, and these elevated levels of KYNA could contribute to NMDAR hypofunction and the cognitive deficits and negative symptoms associated with this disease. However, the impact of endogenously produced KYNA on brain function and behavior is less well understood due to a paucity of pharmacological tools. To address this issue, we identified PF-04859989, a brain-penetrable inhibitor of kynurenine aminotransferase II (KAT II), the enzyme responsible for most brain KYNA synthesis. In rats, systemic administration of PF-04859989 dose-dependently reduced brain KYNA to as little as 28% of basal levels, and prevented amphetamine- and ketamine-induced disruption of auditory gating and improved performance in a sustained attention task. It also prevented ketamine-induced disruption of performance in a working memory task and a spatial memory task in rodents and nonhuman primates, respectively. Together, these findings support the hypotheses that endogenous KYNA impacts cognitive function and that inhibition of KAT II, and consequent lowering of endogenous brain KYNA levels, improves cognitive performance under conditions considered relevant for schizophrenia.

  13. Human functional neuroimaging of brain changes associated with practice

    OpenAIRE

    GARAVAN, HUGH PATRICK

    2005-01-01

    PUBLISHED The discovery that experience-driven changes in the human brain can occur from a neural to a cortical level throughout the lifespan has stimulated a proliferation of research into how neural function changes in response to experience, enabled by neuroimaging methods such as positron emission tomography and functional magnetic resonance imaging. Studies attempt to characterize these changes by examining how practice on a task affects the functional anatomy underlying performance. ...

  14. Human brain networks function in connectome-specific harmonic waves.

    Science.gov (United States)

    Atasoy, Selen; Donnelly, Isaac; Pearson, Joel

    2016-01-21

    A key characteristic of human brain activity is coherent, spatially distributed oscillations forming behaviour-dependent brain networks. However, a fundamental principle underlying these networks remains unknown. Here we report that functional networks of the human brain are predicted by harmonic patterns, ubiquitous throughout nature, steered by the anatomy of the human cerebral cortex, the human connectome. We introduce a new technique extending the Fourier basis to the human connectome. In this new frequency-specific representation of cortical activity, that we call 'connectome harmonics', oscillatory networks of the human brain at rest match harmonic wave patterns of certain frequencies. We demonstrate a neural mechanism behind the self-organization of connectome harmonics with a continuous neural field model of excitatory-inhibitory interactions on the connectome. Remarkably, the critical relation between the neural field patterns and the delicate excitation-inhibition balance fits the neurophysiological changes observed during the loss and recovery of consciousness.

  15. The microbiota-gut-brain axis in functional gastrointestinal disorders.

    Science.gov (United States)

    De Palma, Giada; Collins, Stephen M; Bercik, Premysl

    2014-01-01

    Functional gastrointestinal disorders (FGIDs) are highly prevalent and pose a significant burden on health care and society, and impact patients' quality of life. FGIDs comprise a heterogeneous group of disorders, with unclear underlying pathophysiology. They are considered to result from the interaction of altered gut physiology and psychological factors via the gut-brain axis, where brain and gut symptoms are reciprocally influencing each other's expression. Intestinal microbiota, as a part of the gut-brain axis, plays a central role in FGIDs. Patients with Irritable Bowel Syndrome, a prototype of FGIDs, display altered composition of the gut microbiota compared with healthy controls and benefit, at the gastrointestinal and psychological levels, from the use of probiotics and antibiotics. This review aims to recapitulate the available literature on FGIDs and microbiota-gut-brain axis.

  16. Functional Brain Network Changes Associated with Maintenance of Cognitive Function in Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Santosh A Helekar

    2010-11-01

    Full Text Available In multiple sclerosis (MS functional changes in connectivity due to cortical reorganization could lead to cognitive impairment (CI, or reflect a re-adjustment to reduce the clinical effects of widespread tissue damage. Such alterations in connectivity could result in changes in neural activation as assayed by executive function tasks. We examined cognitive function in MS patients with mild to moderate cognitive impairment and age-matched controls. We evaluated brain activity using functional magnetic resonance imaging (fMRI during the successful performance of the Wisconsin-card sorting (WCS task by MS patients, showing compensatory maintenance of normal function, as measured by response latency and error rate. To assess changes in functional connectivity throughout the brain, we performed a global functional brain network analysis by computing voxel by voxel correlations on the fMRI time series data and carrying out a hierarchical cluster analysis. We found that during the WCS task there is a significant reduction in the number of smaller size brain functional networks, and a change in the brain areas representing the nodes of these networks in MS patients compared to age-matched controls. There is also a concomitant increase in the strength of functional connections between brain loci separated at intermediate scale distances in these patients. These functional alterations might reflect compensatory neuroplastic reorganization underlying maintenance of relatively normal cognitive function in the face of white matter lesions and cortical atrophy produced by MS.

  17. Thyroid, brain and mood modulation in affective disorder: insights from molecular research and functional brain imaging.

    Science.gov (United States)

    Bauer, M; London, E D; Silverman, D H; Rasgon, N; Kirchheiner, J; Whybrow, P C

    2003-11-01

    The efficacy resulting from adjunctive use of supraphysiological doses of levothyroxine has emerged as a promising approach to therapy and prophylaxis for refractory mood disorders. Most patients with mood disorders who receive treatment with supraphysiological doses of levothyroxine have normal peripheral thyroid hormone levels, and also respond differently to the hormone and tolerate it better than healthy individuals and patients with primary thyroid diseases. Progress in molecular and functional brain imaging techniques has provided a new understanding of these phenomena, illuminating the relationship between thyroid function, mood modulation and behavior. Thyroid hormones are widely distributed in the brain and have a multitude of effects on the central nervous system. Notably many of the limbic system structures where thyroid hormone receptors are prevalent have been implicated in the pathogenesis of mood disorders. The influence of the thyroid system on neurotransmitters (particularly serotonin and norepinephrine), which putatively play a major role in the regulation of mood and behavior, may contribute to the mechanisms of mood modulation. Recent functional brain imaging studies using positron emission tomography (PET) with [ (18)F]-fluorodeoxyglucose demonstrated that thyroid hormone treatment with levothyroxine affects regional brain metabolism in patients with hypothyroidism and bipolar disorder. Theses studies confirm that thyroid hormones are active in modulating metabolic function in the mature adult brain, and provide intriging neuroanatomic clues that may guide future research.

  18. Darwin's evolution theory, brain oscillations, and complex brain function in a new "Cartesian view".

    Science.gov (United States)

    Başar, Erol; Güntekin, Bahar

    2009-01-01

    Comparatively analyses of electrophysiological correlates across species during evolution, alpha activity during brain maturation, and alpha activity in complex cognitive processes are presented to illustrate a new multidimensional "Cartesian System" brain function. The main features are: (1) The growth of the alpha activity during evolution, increase of alpha during cognitive processes, and decrease of the alpha entropy during evolution provide an indicator for evolution of brain cognitive performance. (2) Human children younger than 3 years are unable to produce higher cognitive processes and do not show alpha activity till the age of 3 years. The mature brain can perform higher cognitive processes and demonstrates regular alpha activity. (3) Alpha activity also is significantly associated with highly complex cognitive processes, such as the recognition of facial expressions. The neural activity reflected by these brain oscillations can be considered as constituent "building blocks" for a great number of functions. An overarching statement on the alpha function is presented by extended analyzes with multiple dimensions that constitute a "Cartesian Hyperspace" as the basis for oscillatory function. Theoretical implications are considered.

  19. Sleep, Neuronal Plasticity and Brain Function

    NARCIS (Netherlands)

    Meerlo, Peter; Benca, Ruth M.; Abel, Ted

    2015-01-01

    Sleep is truly one of the biggest mysteries in behavioral neuroscience. Humans spend a substantial portion of their lives asleep, as do all other mammalian and bird species that have been studied to date, yet the functions of sleep remain elusive and continue to be a topic of debate among sleep rese

  20. Brain Function in Duchenne Muscular Dystrophy

    Directory of Open Access Journals (Sweden)

    J. Gordon Millichap

    2002-02-01

    Full Text Available The role of dystrophin disorders in the CNS function of boys with Duchenne muscular dystrophy (DMD and the dystrophin-deficient mdx mouse, an animal model of DMD, is reviewed at the University of New South Wales, University of Sydney, Australia.

  1. Insular activation during reward anticipation reflects duration of illness in abstinent pathological gamblers

    Directory of Open Access Journals (Sweden)

    Kosuke eTsurumi

    2014-09-01

    Full Text Available Pathological gambling (PG is a chronic mental disorder characterized by a difficulty restraining gambling behavior despite negative consequences. Although brain abnormalities in patients with substance use disorders are caused by repetitive drug use and recover partly with drug abstinence, the relationship between brain activity and duration of illness or abstinence of gambling behavior in PG patients remains unclear. Here, using functional magnetic resonance imaging, we compared the brain activity of 23 PG patients recruited from a treatment facility with 27 demographically-matched healthy control subjects during reward anticipation, and examined the correlations between brain activity and duration of illness or abstinence in PG patients. During reward anticipation, PG patients showed decreased activity compared to healthy controls in a broad range of the reward system regions, including the insula cortex. In PG patients, activation in the left insula showed a significant negative correlation with illness duration. Our findings suggest that insular activation during reward anticipation may serve as a marker of progression of pathological gambling.

  2. Feedback associated with expectation for larger-reward improves visuospatial working memory performances in children with ADHD

    Directory of Open Access Journals (Sweden)

    Rubi Hammer

    2015-08-01

    Full Text Available We tested the interactive effect of feedback and reward on visuospatial working memory in children with ADHD. Seventeen boys with ADHD and 17 Normal Control (NC boys underwent functional magnetic resonance imaging (fMRI while performing four visuospatial 2-back tasks that required monitoring the spatial location of letters presented on a display. Tasks varied in reward size (large; small and feedback availability (no-feedback; feedback. While the performance of NC boys was high in all conditions, boys with ADHD exhibited higher performance (similar to those of NC boys only when they received feedback associated with large-reward. Performance pattern in both groups was mirrored by neural activity in an executive function neural network comprised of few distinct frontal brain regions. Specifically, neural activity in the left and right middle frontal gyri of boys with ADHD became normal-like only when feedback was available, mainly when feedback was associated with large-reward. When feedback was associated with small-reward, or when large-reward was expected but feedback was not available, boys with ADHD exhibited altered neural activity in the medial orbitofrontal cortex and anterior insula. This suggests that contextual support normalizes activity in executive brain regions in children with ADHD, which results in improved working memory.

  3. Loss of functional GABAA receptors in the Alzheimer diseased brain

    Science.gov (United States)

    Limon, Agenor; Reyes-Ruiz, Jorge Mauricio; Miledi, Ricardo

    2012-01-01

    The cholinergic and glutamatergic neurotransmission systems are known to be severely disrupted in Alzheimer's disease (AD). GABAergic neurotransmission, in contrast, is generally thought to be well preserved. Evidence from animal models and human postmortem tissue suggest GABAergic remodeling in the AD brain. Nevertheless, there is no information on changes, if any, in the electrophysiological properties of human native GABA receptors as a consequence of AD. To gain such information, we have microtransplanted cell membranes, isolated from temporal cortices of control and AD brains, into Xenopus oocytes, and recorded the electrophysiological activity of the transplanted GABA receptors. We found an age-dependent reduction of GABA currents in the AD brain. This reduction was larger when the AD membranes were obtained from younger subjects. We also found that GABA currents from AD brains have a faster rate of desensitization than those from non-AD brains. Furthermore, GABA receptors from AD brains were slightly, but significantly, less sensitive to GABA than receptors from non-AD brains. The reduction of GABA currents in AD was associated with reductions of mRNA and protein of the principal GABA receptor subunits normally present in the temporal cortex. Pairwise analysis of the transcripts within control and AD groups and analyses of the proportion of GABA receptor subunits revealed down-regulation of α1 and γ2 subunits in AD. In contrast, the proportions of α2, β1, and γ1 transcripts were up-regulated in the AD brains. Our data support a functional remodeling of GABAergic neurotransmission in the human AD brain. PMID:22691495

  4. Reward sensitivity for a palatable food reward peaks during pubertal developmental in rats

    Directory of Open Access Journals (Sweden)

    Chris M Friemel

    2010-07-01

    Full Text Available Puberty is a critical period for the initiation of drug use and abuse. Because early drug use onset often accounts for a more severe progression of addiction, it is of importance to understand the underlying mechanisms and neurodevelopmental changes during puberty that are contributing to enhanced reward processing in teenagers. The present study investigated the progression of reward sensitivity towards a natural food reward over the whole course of adolescence in male rats (postnatal days 30–90 by monitoring consummatory, motivational behavior and neurobiological correlates of reward. Using a limited-free intake paradigm, consumption of sweetened condensed milk (SCM was measured repeatedly in adolescent and adult rats. Additionally, early- and mid-pubertal animals were tested in Progressive Ratio responding for SCM and c-fos protein expression in reward-associated brain structures was examined after odor-conditioning for SCM. We found a transient increase in SCM consumption and motivational incentive for SCM during puberty. This increased reward sensitivity was most pronounced around mid-puberty. The behavioral findings are paralleled by enhanced c-fos staining in reward-related structures revealing an intensified neuronal response after reward-cue presentation, distinctive for pubertal animals. Taken together, these data indicate an increase in reward sensitivity during adolescence accompanied by enhanced responsiveness of reward associated brain structures to incentive stimuli, and it seems that both is strongly pronounced around mid-puberty. Therefore, higher reward sensitivity during pubertal maturation might contribute to the enhanced vulnerability of teenagers for the initiation of experimental drug use.

  5. Punished by Rewards?

    Science.gov (United States)

    Brandt, Ron

    1995-01-01

    The author of "Punished by Rewards" (1993), claims that rewards and punishments serve to manipulate behavior and destroy the potential for real learning. Praise is especially tricky, since intangible rewards can also foster compliance, not motivation. An engaging curriculum and a caring atmosphere encourage kids to exercise their natural…

  6. Motivation and reward systems

    NARCIS (Netherlands)

    van Eerde, W.; Vodosek, M.; den Hartog, D.N.; McNett, J.M.

    2014-01-01

    Reward systems are identified as one of the human resource management (HRM) practices that may impact motivation. Reward systems may consist of several components, including financial and nonfinancial rewards, in fixed and variable amounts. Reinforcement, expectancy, and equity principles are discus

  7. Brain Structure-function Couplings (FY11)

    Science.gov (United States)

    2012-01-01

    following have been generated: • Refereed Journal Papers: 1. Lau, T. M.; Gwin, J. T.; McDowell, K.; Ferris, D. P. Weighted Phase Lag Index Stability as an...Environments 3.1 Authors The authors on this project are Scott Kerick from ARL/HRED, Manuel Vindiola from Dynamics Research Corporation ( DRC ), and Kaleb...Project 3: Validating Functional Connectivity Measures Using Neural Mass Models 4.1 Authors The authors on this project are Manuel Vindiola from DRC

  8. Hyperbaric oxygen therapy improves cognitive functioning after brain injury

    Institute of Scientific and Technical Information of China (English)

    Su Liu; Guangyu Shen; Shukun Deng; Xiubin Wang; Qinfeng Wu; Aisong Guo

    2013-01-01

    Hyperbaric oxygen therapy has been widely applied and recognized in the treatment of brain injury;however, the correlation between the protective effect of hyperbaric oxygen therapy and changes of metabolites in the brain remains unclear. To investigate the effect and potential mechanism of hyperbaric oxygen therapy on cognitive functioning in rats, we established traumatic brain injury models using Feeney’s free fal ing method. We treated rat models with hyperbaric oxygen therapy at 0.2 MPa for 60 minutes per day. The Morris water maze test for spatial navigation showed that the average escape latency was significantly prolonged and cognitive function decreased in rats with brain injury. After treatment with hyperbaric oxygen therapy for 1 and 2 weeks, the rats’ spatial learning and memory abilities were improved. Hydrogen proton magnetic resonance spectroscopy analysis showed that the N-acetylaspartate/creatine ratio in the hippocampal CA3 region was sig-nificantly increased at 1 week, and the N-acetylaspartate/choline ratio was significantly increased at 2 weeks after hyperbaric oxygen therapy. Nissl staining and immunohistochemical staining showed that the number of nerve cells and Nissl bodies in the hippocampal CA3 region was significantly increased, and glial fibril ary acidic protein positive cells were decreased after a 2-week hyperbaric oxygen therapy treatment. Our findings indicate that hyperbaric oxygen therapy significantly im-proves cognitive functioning in rats with traumatic brain injury, and the potential mechanism is me-diated by metabolic changes and nerve cellrestoration in the hippocampal CA3 region.

  9. Hyperbaric oxygen therapy improves cognitive functioning after brain injury.

    Science.gov (United States)

    Liu, Su; Shen, Guangyu; Deng, Shukun; Wang, Xiubin; Wu, Qinfeng; Guo, Aisong

    2013-12-15

    Hyperbaric oxygen therapy has been widely applied and recognized in the treatment of brain injury; however, the correlation between the protective effect of hyperbaric oxygen therapy and changes of metabolites in the brain remains unclear. To investigate the effect and potential mechanism of hyperbaric oxygen therapy on cognitive functioning in rats, we established traumatic brain injury models using Feeney's free falling method. We treated rat models with hyperbaric oxygen therapy at 0.2 MPa for 60 minutes per day. The Morris water maze test for spatial navigation showed that the average escape latency was significantly prolonged and cognitive function decreased in rats with brain injury. After treatment with hyperbaric oxygen therapy for 1 and 2 weeks, the rats' spatial learning and memory abilities were improved. Hydrogen proton magnetic resonance spectroscopy analysis showed that the N-acetylaspartate/creatine ratio in the hippocampal CA3 region was significantly increased at 1 week, and the N-acetylaspartate/choline ratio was significantly increased at 2 weeks after hyperbaric oxygen therapy. Nissl staining and immunohistochemical staining showed that the number of nerve cells and Nissl bodies in the hippocampal CA3 region was significantly increased, and glial fibrillary acidic protein positive cells were decreased after a 2-week hyperbaric oxygen therapy treatment. Our findings indicate that hyperbaric oxygen therapy significantly improves cognitive functioning in rats with traumatic brain injury, and the potential mechanism is mediated by metabolic changes and nerve cell restoration in the hippocampal CA3 region.

  10. Effects of soccer heading on brain structure and function

    Directory of Open Access Journals (Sweden)

    Ana Carolina Oliveira Rodrigues

    2016-03-01

    Full Text Available Soccer is the most popular sport in the world, with more than 265 million players worldwide, including professional and amateur ones. Soccer is unique in comparison to other sports, as it is the only sport in which participants purposely use their head to hit the ball. Heading is considered an offensive or defensive move whereby the player’s unprotected head is used to deliberately impact the ball and direct it during play. A soccer player can be subjected to an average of six to twelve incidents of heading the ball per competitive game, where the ball reaches high velocities. Moreover, in practice sessions, heading training, which involves heading the ball repeatedly at low velocities, is common. Although the scientific community, as well as the media, has focused on the effects of concussions in contact sports, the role of subconcussive impacts, as it can occur during heading, has recently gained attention, considering that it may represent an additional mechanism of cumulative brain injury. The purpose of this study is to review the existing literature regarding the effects of soccer heading on brain structure and function. Only in the last years some investigations have addressed the impact of heading on brain structure, by using neuroimaging techniques. Similarly, there have been some recent studies investigating biochemical markers of brain injury in soccer players. There is evidence of association between heading and abnormal brain structure, but the data are still preliminary. Also, some studies have suggested that subconcussive head impacts, as heading, could cause cognitive impairment, whereas others have not corroborated this finding. Questions persist as to whether or not heading is deleterious to cognitive functioning. Further studies, especially with longitudinal designs, are needed to clarify the clinical significance of heading as a cause of brain injury and to identify risk factors. Such investigations might contribute to the

  11. Efficiency and cost of economical brain functional networks.

    Directory of Open Access Journals (Sweden)

    Sophie Achard

    2007-02-01

    Full Text Available Brain anatomical networks are sparse, complex, and have economical small-world properties. We investigated the efficiency and cost of human brain functional networks measured using functional magnetic resonance imaging (fMRI in a factorial design: two groups of healthy old (N = 11; mean age = 66.5 years and healthy young (N = 15; mean age = 24.7 years volunteers were each scanned twice in a no-task or "resting" state following placebo or a single dose of a dopamine receptor antagonist (sulpiride 400 mg. Functional connectivity between 90 cortical and subcortical regions was estimated by wavelet correlation analysis, in the frequency interval 0.06-0.11 Hz, and thresholded to construct undirected graphs. These brain functional networks were small-world and economical in the sense of providing high global and local efficiency of parallel information processing for low connection cost. Efficiency was reduced disproportionately to cost in older people, and the detrimental effects of age on efficiency were localised to frontal and temporal cortical and subcortical regions. Dopamine antagonism also impaired global and local efficiency of the network, but this effect was differentially localised and did not interact with the effect of age. Brain functional networks have economical small-world properties-supporting efficient parallel information transfer at relatively low cost-which are differently impaired by normal aging and pharmacological blockade of dopamine transmission.

  12. Functional constraints in the evolution of brain circuits

    Science.gov (United States)

    Bosman, Conrado A.; Aboitiz, Francisco

    2015-01-01

    Regardless of major anatomical and neurodevelopmental differences, the vertebrate isocortex shows a remarkably well-conserved organization. In the isocortex, reciprocal connections between excitatory and inhibitory neurons are distributed across multiple layers, encompassing modular, dynamical and recurrent functional networks during information processing. These dynamical brain networks are often organized in neuronal assemblies interacting through rhythmic phase relationships. Accordingly, these oscillatory interactions are observed across multiple brain scale levels, and they are associated with several sensory, motor, and cognitive processes. Most notably, oscillatory interactions are also found in the complete spectrum of vertebrates. Yet, it is unknown why this functional organization is so well conserved in evolution. In this perspective, we propose some ideas about how functional requirements of the isocortex can account for the evolutionary stability observed in microcircuits across vertebrates. We argue that isocortex architectures represent canonical microcircuits resulting from: (i) the early selection of neuronal architectures based on the oscillatory excitatory-inhibitory balance, which lead to the implementation of compartmentalized oscillations and (ii) the subsequent emergence of inferential coding strategies (predictive coding), which are able to expand computational capacities. We also argue that these functional constraints may be the result of several advantages that oscillatory activity contributes to brain network processes, such as information transmission and code reliability. In this manner, similarities in mesoscale brain circuitry and input-output organization between different vertebrate groups may reflect evolutionary constraints imposed by these functional requirements, which may or may not be traceable to a common ancestor. PMID:26388716

  13. Regret-based Reward Elicitation for Markov Decision Processes

    CERN Document Server

    Regan, Kevin

    2012-01-01

    The specification of aMarkov decision process (MDP) can be difficult. Reward function specification is especially problematic; in practice, it is often cognitively complex and time-consuming for users to precisely specify rewards. This work casts the problem of specifying rewards as one of preference elicitation and aims to minimize the degree of precision with which a reward function must be specified while still allowing optimal or near-optimal policies to be produced. We first discuss how robust policies can be computed for MDPs given only partial reward information using the minimax regret criterion. We then demonstrate how regret can be reduced by efficiently eliciting reward information using bound queries, using regret-reduction as a means for choosing suitable queries. Empirical results demonstrate that regret-based reward elicitation offers an effective way to produce near-optimal policies without resorting to the precise specification of the entire reward function.

  14. Continuous theta burst transcranial magnetic stimulation affects brain functional connectivity.

    Science.gov (United States)

    Dan Cao; Yingjie Li; Ling Wei; Yingying Tang

    2016-08-01

    Prefrontal cortex (PFC) plays an important role in the emotional processing as well as in the functional brain network. Hyperactivity in the right dorsolateral prefrontal cortex (DLPFC) would be found in anxious participants. However, it is still unclear what the role of PFC played in a resting functional network. Continuous theta burst transcranial magnetic stimulation (cTBS) is an effective tool to create virtual lesions on brain regions. In this paper, we applied cTBS over right prefrontal area, and investigated the effects of cTBS on the brain activity for functional connectivity by the method of graph theory. We recorded 64-channels EEG on thirteen healthy participants in the resting condition and emotional tasks before and after 40 s of cTBS. This work focused on the effect of cTBS on cortical activities in the resting condition by calculating the coherence between EEG channels and building functional networks before and after cTBS in the delta, theta, alpha and beta bands. Results revealed that 1) The functional connectivity after cTBS was significantly increased compared with that before cTBS in delta, theta, alpha and beta bands in the resting condition; 2) The efficiency-cost reached the maximum before and after cTBS both with the cost about 0.3 in the bands above, which meant that the information transmission of functional brain network with this cost was highly efficient; 3) the clustering coefficient and path length after cTBS was significantly increased in delta, theta and beta bands. In conclusion, cTBS over PFC indeed enhanced the functional connectivity in the resting condition. In addition, the information transmission in the resting brain network was highly efficient with the cost about 0.3.

  15. A Functional 3'UTR Polymorphism (rs2235749) of Prodynorphin Alters microRNA-365 Binding in Ventral Striatonigral Neurons to Influence Novelty Seeking and Positive Reward Traits.

    Science.gov (United States)

    Egervari, Gabor; Jutras-Aswad, Didier; Landry, Joseph; Miller, Michael L; Anderson, Sarah Ann; Michaelides, Michael; Jacobs, Michelle M; Peter, Cyril; Yiannoulos, Georgia; Liu, Xun; Hurd, Yasmin L

    2016-09-01

    Genetic factors impact behavioral traits relevant to numerous psychiatric disorders and risk-taking behaviors, and different lines of evidence have indicated that discrete neurobiological systems contribute to such individual differences. In this study, we explored the relationship of genetic variants of the prodynorphin (PDYN) gene, which is enriched in the striatonigral/striatomesencephalic pathway, a key neuronal circuit implicated in positive 'Go' behavioral choice and action. Our multidisciplinary approach revealed that the single nucleotide polymorphism (SNP) rs2235749 (in high linkage disequilibrium with rs910080) modifies striatal PDYN expression via impaired binding of miR-365, a microRNA that targets the PDYN 3'-untranslated region (3'UTR), and is significantly associated to novelty- and reward-related behavioral traits in humans and translational animal models. Carriers of the rs2235749G allele exhibited increased levels of PDYN 3'UTR in vitro and had elevated mRNA expression in the medial nucleus accumbens shell (NAcSh) and caudate nucleus in postmortem human brains. There was an association of rs2235749 with novelty-seeking trait and a strong genotype-dose association with positive reinforcement behavior in control subjects, which differed in cannabis-dependent individuals. Using lentiviral miRZip-365 constructs selectively expressed in Pdyn-neurons of the NAcSh, we demonstrated that the Pdyn-miR365 interaction in the NAcSh directly influences novelty-seeking exploratory behavior and facilitates self-administration of natural reward. Overall, this translational study suggests that genetically determined miR-365-mediated epigenetic regulation of PDYN expression in mesolimbic striatonigral/striatomesencephalic circuits possibly contributes to novelty seeking and positive reinforcement traits.

  16. Demonstration: A smartphone 3D functional brain scanner

    DEFF Research Database (Denmark)

    Stahlhut, Carsten; Stopczynski, Arkadiusz; Larsen, Jakob Eg

    We demonstrate a fully portable 3D real-time functional brain scanner consisting of a wireless 14-channel ‘Neuroheadset‘ (Emotiv EPOC) and a Nokia N900 smartphone. The novelty of our system is the ability to perform real-time functional brain imaging on a smartphone device, including stimulus...... delivery, data acquisition, logging, brain state decoding, and 3D visualization of the cortical EEG sources. Custom-made software realized in Qt has been implemented on the phone, which allow for either the phone to process the EEG data locally or transmit it to a server when more advanced machine learning......, tablet computers, and netbooks) that are based on Linux operating systems....

  17. A Cellular Perspective on Brain Energy Metabolism and Functional Imaging

    KAUST Repository

    Magistretti, Pierre J.

    2015-05-01

    The energy demands of the brain are high: they account for at least 20% of the body\\'s energy consumption. Evolutionary studies indicate that the emergence of higher cognitive functions in humans is associated with an increased glucose utilization and expression of energy metabolism genes. Functional brain imaging techniques such as fMRI and PET, which are widely used in human neuroscience studies, detect signals that monitor energy delivery and use in register with neuronal activity. Recent technological advances in metabolic studies with cellular resolution have afforded decisive insights into the understanding of the cellular and molecular bases of the coupling between neuronal activity and energy metabolism and pointat a key role of neuron-astrocyte metabolic interactions. This article reviews some of the most salient features emerging from recent studies and aims at providing an integration of brain energy metabolism across resolution scales. © 2015 Elsevier Inc.

  18. Transfer of neuroplasticity from nucleus accumbens core to shell is required for cocaine reward.

    Directory of Open Access Journals (Sweden)

    Nicolas Marie

    Full Text Available It is well established that cocaine induces an increase of dendritic spines density in some brain regions. However, few studies have addressed the role of this neuroplastic changes in cocaine rewarding effects and have often led to contradictory results. So, we hypothesized that using a rigorous time- and subject-matched protocol would demonstrate the role of this spine increase in cocaine reward. We designed our experiments such as the same animals (rats were used for spine analysis and behavioral studies. Cocaine rewarding effects were assessed with the conditioned place preference paradigm. Spines densities were measured in the two subdivisions of the nucleus accumbens (NAcc, core and shell. We showed a correlation between the increase of spine density in NAcc core and shell and cocaine rewarding effects. Interestingly, when cocaine was administered in home cages, spine density was increase in NAcc core only. With anisomycin, a protein synthesis inhibitor, injected in the core we blocked spine increase in core and shell and also cocaine rewarding effects. Strikingly, whereas injection of this inhibitor in the shell immediately after conditioning had no effect on neuroplasticity or behavior, its injection 4 hours after conditioning was able to block neuroplasticity in shell only and cocaine-induced place preference. Thus, it clearly appears that the neuronal plasticity in the NAcc core is essential to induce plasticity in the shell, necessary for cocaine reward. Altogether, our data revealed a new mechanism in the NAcc functioning where a neuroplasticity transfer occurred from core to shell.

  19. Temporal dynamics of prediction error processing during reward-based decision making.

    Science.gov (United States)

    Philiastides, Marios G; Biele, Guido; Vavatzanidis, Niki; Kazzer, Philipp; Heekeren, Hauke R

    2010-10-15

    Adaptive decision making depends on the accurate representation of rewards associated with potential choices. These representations can be acquired with reinforcement learning (RL) mechanisms, which use the prediction error (PE, the difference between expected and received rewards) as a learning signal to update reward expectations. While EEG experiments have highlighted the role of feedback-related potentials during performance monitoring, important questions about the temporal sequence of feedback processing and the specific function of feedback-related potentials during reward-based decision making remain. Here, we hypothesized that feedback processing starts with a qualitative evaluation of outcome-valence, which is subsequently complemented by a quantitative representation of PE magnitude. Results of a model-based single-trial analysis of EEG data collected during a reversal learning task showed that around 220ms after feedback outcomes are initially evaluated categorically with respect to their valence (positive vs. negative). Around 300ms, and parallel to the maintained valence-evaluation, the brain also represents quantitative information about PE magnitude, thus providing the complete information needed to update reward expectations and to guide adaptive decision making. Importantly, our single-trial EEG analysis based on PEs from an RL model showed that the feedback-related potentials do not merely reflect error awareness, but rather quantitative information crucial for learning reward contingencies.

  20. Listening to music in a risk-reward context: The roles of the temporoparietal junction and the orbitofrontal/insular cortices in reward-anticipation, reward-gain, and reward-loss.

    Science.gov (United States)

    Li, Chia-Wei; Chen, Jyh-Horng; Tsai, Chen-Gia

    2015-12-10

    Artificial rewards, such as visual arts and music, produce pleasurable feelings. Popular songs in the verse-chorus form provide a useful model for understanding the neural mechanisms underlying the processing of artificial rewards, because the chorus is usually the most rewarding element of a song. In this functional magnetic resonance imaging (fMRI) study, the stimuli were excerpts of 10 popular songs with a tensioned verse-to-chorus transition. We examined the neural correlates of three phases of reward processing: (1) reward-anticipation during the verse-to-chorus transition, (2) reward-gain during the first phrase of the chorus, and (3) reward-loss during the unexpected noise followed by the verse-to-chorus transition. Participants listened to these excerpts in a risk-reward context because the verse was followed by either the chorus or noise with equal probability. The results showed that reward-gain and reward-loss were associated with left- and right-biased temporoparietal junction activation, respectively. The bilateral temporoparietal junctions were active during reward-anticipation. Moreover, we observed left-biased lateral orbitofrontal activation during reward-anticipation, whereas the medial orbitofrontal cortex was activated during reward-gain. The findings are discussed in relation to the cognitive and emotional aspects of reward processing.

  1. Disrupted functional brain connectome in unilateral sudden sensorineural hearing loss.

    Science.gov (United States)

    Xu, Haibo; Fan, Wenliang; Zhao, Xueyan; Li, Jing; Zhang, Wenjuan; Lei, Ping; Liu, Yuan; Wang, Haha; Cheng, Huamao; Shi, Hong

    2016-05-01

    Sudden sensorineural hearing loss (SSNHL) is generally defined as sensorineural hearing loss of 30 dB or greater over at least three contiguous audiometric frequencies and within a three-day period. This hearing loss is usually unilateral and can be associated with tinnitus and vertigo. The pathogenesis of unilateral sudden sensorineural hearing loss is still unknown, and the alterations in the functional connectivity are suspected to involve one possible pathogenesis. Despite scarce findings with respect to alterations in brain functional networks in unilateral sudden sensorineural hearing loss, the alterations of the whole brain functional connectome and whether these alterations were already in existence in the acute period remains unknown. The aim of this study was to investigate the alterations of brain functional connectome in two large samples of unilateral sudden sensorineural hearing loss patients and to investigate the correlation between unilateral sudden sensorineural hearing loss characteristics and changes in the functional network properties. Pure tone audiometry was performed to assess hearing ability. Abnormal changes in the peripheral auditory system were examined using conventional magnetic resonance imaging. The graph theoretical network analysis method was used to detect brain connectome alterations in unilateral sudden sensorineural hearing loss. Compared with the control groups, both groups of unilateral SSNHL patients exhibited a significantly increased clustering coefficient, global efficiency, and local efficiency but a significantly decreased characteristic path length. In addition, the primary increased nodal strength (e.g., nodal betweenness, hubs) was observed in several regions primarily, including the limbic and paralimbic systems, and in the auditory network brain areas. These findings suggest that the alteration of network organization already exists in unilateral sudden sensorineural hearing loss patients within the acute period

  2. Variability in functional brain networks predicts expertise during action observation.

    Science.gov (United States)

    Amoruso, Lucía; Ibáñez, Agustín; Fonseca, Bruno; Gadea, Sebastián; Sedeño, Lucas; Sigman, Mariano; García, Adolfo M; Fraiman, Ricardo; Fraiman, Daniel

    2017-02-01

    Observing an action performed by another individual activates, in the observer, similar circuits as those involved in the actual execution of that action. This activation is modulated by prior experience; indeed, sustained training in a particular motor domain leads to structural and functional changes in critical brain areas. Here, we capitalized on a novel graph-theory approach to electroencephalographic data (Fraiman et al., 2016) to test whether variability in functional brain networks implicated in Tango observation can discriminate between groups differing in their level of expertise. We found that experts and beginners significantly differed in the functional organization of task-relevant networks. Specifically, networks in expert Tango dancers exhibited less variability and a more robust functional architecture. Notably, these expertise-dependent effects were captured within networks derived from electrophysiological brain activity recorded in a very short time window (2s). In brief, variability in the organization of task-related networks seems to be a highly sensitive indicator of long-lasting training effects. This finding opens new methodological and theoretical windows to explore the impact of domain-specific expertise on brain plasticity, while highlighting variability as a fruitful measure in neuroimaging research.

  3. Dehydration affects brain structure and function in healthy adolescents.

    Science.gov (United States)

    Kempton, Matthew J; Ettinger, Ulrich; Foster, Russell; Williams, Steven C R; Calvert, Gemma A; Hampshire, Adam; Zelaya, Fernando O; O'Gorman, Ruth L; McMorris, Terry; Owen, Adrian M; Smith, Marcus S

    2011-01-01

    It was recently observed that dehydration causes shrinkage of brain tissue and an associated increase in ventricular volume. Negative effects of dehydration on cognitive performance have been shown in some but not all studies, and it has also been reported that an increased perceived effort may be required following dehydration. However, the effects of dehydration on brain function are unknown. We investigated this question using functional magnetic resonance imaging (fMRI) in 10 healthy adolescents (mean age = 16.8, five females). Each subject completed a thermal exercise protocol and nonthermal exercise control condition in a cross-over repeated measures design. Subjects lost more weight via perspiration in the thermal exercise versus the control condition (P Dehydration following the thermal exercise protocol led to a significantly stronger increase in fronto-parietal blood-oxygen-level-dependent (BOLD) response during an executive function task (Tower of London) than the control condition, whereas cerebral perfusion during rest was not affected. The increase in BOLD response after dehydration was not paralleled by a change in cognitive performance, suggesting an inefficient use of brain metabolic activity following dehydration. This pattern indicates that participants exerted a higher level of neuronal activity in order to achieve the same performance level. Given the limited availability of brain metabolic resources, these findings suggest that prolonged states of reduced water intake may adversely impact executive functions such as planning and visuo-spatial processing.

  4. Excitotoxic lesions of the medial striatum delay extinction of a reinforcement color discrimination operant task in domestic chicks; a functional role of reward anticipation.

    Science.gov (United States)

    Ichikawa, Yoko; Izawa, Ei-Ichi; Matsushima, Toshiya

    2004-12-01

    To reveal the functional roles of the striatum, we examined the effects of excitotoxic lesions to the bilateral medial striatum (mSt) and nucleus accumbens (Ac) in a food reinforcement color discrimination operant task. With a food reward as reinforcement, 1-week-old domestic chicks were trained to peck selectively at red and yellow beads (S+) and not to peck at a blue bead (S-). Those chicks then received either lesions or sham operations and were tested in extinction training sessions, during which yellow turned out to be nonrewarding (S-), whereas red and blue remained unchanged. To further examine the effects on postoperant noninstrumental aspects of behavior, we also measured the "waiting time", during which chicks stayed at the empty feeder after pecking at yellow. Although the lesioned chicks showed significantly higher error rates in the nonrewarding yellow trials, their postoperant waiting time gradually decreased similarly to the sham controls. Furthermore, the lesioned chicks waited significantly longer than the controls, even from the first extinction block. In the blue trials, both lesioned and sham chicks consistently refrained from pecking, indicating that the delayed extinction was not due to a general disinhibition of pecking. Similarly, no effects were found in the novel training sessions, suggesting that the lesions had selective effects on the extinction of a learned operant. These results suggest that a neural representation of memory-based reward anticipation in the mSt/Ac could contribute to the anticipation error required for extinction.

  5. Abnormal brain functional connectivity of the hypothalamus in cluster headaches.

    Directory of Open Access Journals (Sweden)

    Enchao Qiu

    Full Text Available The aim of this study was to detect the abnormality of the brain functional connectivity of the hypothalamus during acute spontaneous cluster headache (CH attacks ('in attack' and headache-free intervals ('out of attack' using resting-state functional magnetic resonance imaging (RS-fMRI technique. The RS-fMRI data from twelve male CH patients during 'in attack' and 'out of attack' periods and twelve age- and sex-matched normal controls were analyzed by the region-of-interest -based functional connectivity method using SPM5 software. Abnormal brain functional connectivity of the hypothalamus is present in CH, which is located mainly in the pain system during the spontaneous CH attacks. It extends beyond the pain system during CH attack intervals.

  6. Brain Functional Connectivity in MS: An EEG-NIRS Study

    Science.gov (United States)

    2015-10-01

    oxygen- based ( near -infrared spectroscopy (NIRS), functional MRI (fMRI)) signals, and to use the results to help optimize BOLD fMRI analyses of brain...2. Keywords BOLD – blood oxygen level dependent EEG – electroencephalography NIRS – near -infrared spectroscopy fMRI – functional MRI MS...INTRODUCTION TO ELECTROENCEPHALOGRAPHY AND NEAR -INFRARED SPECTROSCOPY NEUROIMAGING MEASUREMENT AND ANALYSIS P.40LO GlACO~lETTT 1. COURSE O VERVIEW T he

  7. Left Brain vs. Right Brain: Findings on Visual Spatial Capacities and the Functional Neurology of Giftedness

    Science.gov (United States)

    Kalbfleisch, M. Layne; Gillmarten, Charles

    2013-01-01

    As neuroimaging technologies increase their sensitivity to assess the function of the human brain and results from these studies draw the attention of educators, it becomes paramount to identify misconceptions about what these data illustrate and how these findings might be applied to educational contexts. Some of these "neuromyths" have…

  8. The automatic brain: studies on practice and brain function in healthy subjects and patients with schizophrenia

    NARCIS (Netherlands)

    van Raalten, T.R.

    2009-01-01

    Practice makes perfect. The neural mechanisms behind the behavioral improvement of practice (automatization) however are largely unknown. Here we investigate how practice changes brain function and how this can improve our processing capacity. We also examine whether a deficit in automatization can

  9. Pro-cognitive drug effects modulate functional brain network organization

    Directory of Open Access Journals (Sweden)

    Carsten eGiessing

    2012-08-01

    Full Text Available Previous studies document that cholinergic and noradrenergic drugs improve attention, memory and cognitive control in healthy subjects and patients with neuropsychiatric disorders. In humans neural mechanisms of cholinergic and noradrenergic modulation have mainly been analyzed by investigating drug-induced changes of task-related neural activity measured with fMRI. Endogenous neural activity has often been neglected. Further, although drugs affect the coupling between neurons, only a few human studies have explicitly addressed how drugs modulate the functional connectome, i.e. the functional neural interactions within the brain. These studies have mainly focused on synchronization or correlation of brain activations. Recently, there are some drug studies using graph theory and other new mathematical approaches to model the brain as a complex network of interconnected processing nodes. Using such measures it is possible to detect not only focal, but also subtle, widely distributed drug effects on functional network topology. Most important, graph theoretical measures also quantify whether drug-induced changes in topology or network organization facilitate or hinder information processing. Several studies could show that functional brain integration is highly correlated with behavioral performance suggesting that cholinergic and noradrenergic drugs which improve measures of cognitive performance should increase functional network integration. The purpose of this paper is to show that graph theory provides a mathematical tool to develop theory-driven biomarkers of pro-cognitive drug effects, and also to discuss how these approaches can contribute to the understanding of the role of cholinergic and noradrenergic modulation in the human brain. Finally we discuss the global workspace theory as a theoretical framework of pro-cognitive drug effects and argue that pro-cognitive effects of cholinergic and noradrenergic drugs might be related to higher

  10. Cannabidiol inhibits the reward-facilitating effect of morphine: involvement of 5-HT1A receptors in the dorsal raphe nucleus.

    Science.gov (United States)

    Katsidoni, Vicky; Anagnostou, Ilektra; Panagis, George

    2013-03-01

    Cannabidiol is a non-psychotomimetic constituent of Cannabis sativa, which induces central effects in rodents. It has been shown that cannabidiol attenuates cue-induced reinstatement of heroin seeking. However, to the best of our knowledge, its effects on brain stimulation reward and the reward-facilitating effects of drugs of abuse have not yet been examined. Therefore, we investigated the effects of cannabidiol on brain reward function and on the reward-facilitating effect of morphine and cocaine using the intracranial self-stimulation (ICSS) paradigm. Rats were prepared with a stimulating electrode into the medial forebrain bundle (MFB), and a guide cannula into the dorsal raphe (microinjection experiments), and were trained to respond for electrical brain stimulation. A low dose of cannabidiol did not affect the reinforcing efficacy of brain stimulation, whereas higher doses significantly elevated the threshold frequency required for MFB ICSS. Both cocaine and morphine lowered ICSS thresholds. Cannabidiol inhibited the reward-facilitating effect of morphine, but not cocaine. This effect was reversed by pre-treatment with an intra-dorsal raphe injection of the selective 5-HT1A receptor antagonist WAY-100635. The present findings indicate that cannabidiol does not exhibit reinforcing properties in the ICSS paradigm at any of the doses tested, while it decreases the reward-facilitating effects of morphine. These effects were mediated by activation of 5-HT1A receptors in the dorsal raphe. Our results suggest that cannabidiol interferes with brain reward mechanisms responsible for the expression of the acute reinforcing properties of opioids, thus indicating that cannabidiol may be clinically useful in attenuating the rewarding effects of opioids.

  11. Impaired cross-talk between mesolimbic food reward processing and metabolic signaling predicts body mass index

    Directory of Open Access Journals (Sweden)

    Joe J Simon

    2014-10-01

    Full Text Available The anticipation of the pleasure derived from food intake drives the motivation to eat, and hence facilitate overconsumption of food which ultimately results in obesity. Brain imaging studies provide evidence that mesolimbic brain regions underlie both general as well as food related anticipatory reward processing. In light of this knowledge, the present study examined the neural responsiveness of the ventral striatum in participants with a broad BMI spectrum. The study differentiated between general (i.e. monetary and food related anticipatory reward processing. We recruited a sample of volunteers with greatly varying body weights, ranging from a low BMI (below 20 kg/m² over a normal (20 to 25 kg/m² and overweight (25 to 30 kg/m² BMI, to class I (30 to 35 kg/m² and class II (35 to 40 kg/m² obesity. A total of 24 participants underwent functional magnetic resonance imaging whilst performing both a food and monetary incentive delay task, which allows to measure neural activation during the anticipation of rewards. After the presentation of a cue indicating the amount of food or money to be won, participants had to react correctly in order to earn snack points or money coins which could then be exchanged for real food or money, respectively, at the end of the experiment. During the anticipation of both types of rewards, participants displayed activity in the ventral striatum, a region that plays a pivotal role in the anticipation of rewards. Additionally, we observed that specifically anticipatory food reward processing predicted the individual BMI (current and maximum lifetime. This relation was found to be mediated by impaired hormonal satiety signaling, i.e. increased leptin levels and insulin resistance. These findings suggest that heightened food reward motivation contributes to obesity through impaired metabolic signaling.

  12. Neurolinguistics: Structure, Function, and Connectivity in the Bilingual Brain

    Directory of Open Access Journals (Sweden)

    Becky Wong

    2016-01-01

    Full Text Available Advances in neuroimaging techniques and analytic methods have led to a proliferation of studies investigating the impact of bilingualism on the cognitive and brain systems in humans. Lately, these findings have attracted much interest and debate in the field, leading to a number of recent commentaries and reviews. Here, we contribute to the ongoing discussion by compiling and interpreting the plethora of findings that relate to the structural, functional, and connective changes in the brain that ensue from bilingualism. In doing so, we integrate theoretical models and empirical findings from linguistics, cognitive/developmental psychology, and neuroscience to examine the following issues: (1 whether the language neural network is different for first (dominant versus second (nondominant language processing; (2 the effects of bilinguals’ executive functioning on the structure and function of the “universal” language neural network; (3 the differential effects of bilingualism on phonological, lexical-semantic, and syntactic aspects of language processing on the brain; and (4 the effects of age of acquisition and proficiency of the user’s second language in the bilingual brain, and how these have implications for future research in neurolinguistics.

  13. Neurolinguistics: Structure, Function, and Connectivity in the Bilingual Brain.

    Science.gov (United States)

    Wong, Becky; Yin, Bin; O'Brien, Beth

    2016-01-01

    Advances in neuroimaging techniques and analytic methods have led to a proliferation of studies investigating the impact of bilingualism on the cognitive and brain systems in humans. Lately, these findings have attracted much interest and debate in the field, leading to a number of recent commentaries and reviews. Here, we contribute to the ongoing discussion by compiling and interpreting the plethora of findings that relate to the structural, functional, and connective changes in the brain that ensue from bilingualism. In doing so, we integrate theoretical models and empirical findings from linguistics, cognitive/developmental psychology, and neuroscience to examine the following issues: (1) whether the language neural network is different for first (dominant) versus second (nondominant) language processing; (2) the effects of bilinguals' executive functioning on the structure and function of the "universal" language neural network; (3) the differential effects of bilingualism on phonological, lexical-semantic, and syntactic aspects of language processing on the brain; and (4) the effects of age of acquisition and proficiency of the user's second language in the bilingual brain, and how these have implications for future research in neurolinguistics.

  14. Mapping Multiplex Hubs in Human Functional Brain Networks

    Science.gov (United States)

    De Domenico, Manlio; Sasai, Shuntaro; Arenas, Alex

    2016-01-01

    Typical brain networks consist of many peripheral regions and a few highly central ones, i.e., hubs, playing key functional roles in cerebral inter-regional interactions. Studies have shown that networks, obtained from the analysis of specific frequency components of brain activity, present peculiar architectures with unique profiles of region centrality. However, the identification of hubs in networks built from different frequency bands simultaneously is still a challenging problem, remaining largely unexplored. Here we identify each frequency component with one layer of a multiplex network and face this challenge by exploiting the recent advances in the analysis of multiplex topologies. First, we show that each frequency band carries unique topological information, fundamental to accurately model brain functional networks. We then demonstrate that hubs in the multiplex network, in general different from those ones obtained after discarding or aggregating the measured signals as usual, provide a more accurate map of brain's most important functional regions, allowing to distinguish between healthy and schizophrenic populations better than conventional network approaches. PMID:27471443

  15. Brain structural and functional correlates of resilience to Bipolar Disorder

    Directory of Open Access Journals (Sweden)

    Sophia eFrangou

    2012-01-01

    Full Text Available Background: Resilient adaptation can be construed in different ways, but as used here it refers to the adaptive brain changes associated with avoidance of psychopathology despite familiar risk for Bipolar Disorder (BD. Although family history of BD is associated with elevated risk of affective morbidity a significant proportion of first-degree relatives of BD patients remains free of psychopathology. Examination of brain structure and function in these individuals may inform on adaptive changes that may pre-empt disease expression. Methods: Data presented here are derived from the Vulnerability to Bipolar Disorders (VIBES study which includes patients with BD, asymptomatic relatives and healthy controls. Participants underwent extensive investigations including brain structural (sMRI and functional magnetic resonance imaging (fMRI. The data presented here focus on sMRI voxel-based-morphometry and on conventional and connectivity analyses of fMRI data obtained during the Stroop Colour Word Test (SCWT, a task of cognitive control during conflict resolution. All analyses were implemented in SPM (www.fil.ion.ucl.ac.uk/spm. Resilience in relatives was operationalized as the absence of clinical-range symptoms.Results: Resilient relatives of BD patients expressed structural, functional and connectivity changes reflecting the effect of genetic risk on the brain. These included increased insular volume, decreased activation within the posterior and inferior parietal regions involved in selective attention during the SCWT, and reduced fronto-insular and fronto-cingulate connectivity.Resilience was associated with increased cerebellar vermal volume and enhanced functional coupling between the dorsal and the ventral prefrontal cortex. Conclusions: Our findings suggests the presence of biological mechanisms associated with resilient adaptation of brain networks and pave the way for the identification of outcome-specific trajectories given a particular

  16. Partial sleep in the context of augmentation of brain function.

    Directory of Open Access Journals (Sweden)

    Ivan N. Pigarev

    2014-05-01

    Full Text Available Inability to solve complex problems or errors in decision making is often attributed to poor brain processing, and raises the issue of brain augmentation. Investigation of neuronal activity in the cerebral cortex in the sleep-wake cycle offers insights into the mechanisms underlying the reduction in mental abilities for complex problem solving. Some cortical areas may transit into a sleep state while an organism is still awake. Such local sleep would reduce behavioral ability in the tasks for which the sleeping areas are crucial. The studies of this phenomenon have indicated that local sleep develops in high order cortical areas. This is why complex problem solving is mostly affected by local sleep, and prevention of local sleep might be a potential way of augmentation of brain function. For this approach to brain augmentation not to entail negative consequences for the organism, it is necessary to understand the functional role of sleep. Our studies have given an unexpected answer to this question. It was shown that cortical areas that process signals from extero- and proprioreceptors during wakefulness, switch to the processing of interoceptive information during sleep. It became clear that during sleep all computational power of the brain is directed to the restoration of the vital functions of internal organs. These results explain the logic behind the initiation of total and local sleep. Indeed, a mismatch between the current parameters of any visceral system and the genetically determined normal range would provide the feeling of tiredness, or sleep pressure. If an environmental situation allows falling asleep, the organism would transit to a normal total sleep in all cortical areas. However, if it is impossible to go to sleep immediately, partial sleep may develop in some cortical areas in the still behaviorally awake organism. This local sleep may reduce both the intellectual power and the restorative function of sleep for visceral

  17. Dynamic reorganization of intrinsic functional networks in the mouse brain.

    Science.gov (United States)

    Grandjean, Joanes; Preti, Maria Giulia; Bolton, Thomas A W; Buerge, Michaela; Seifritz, Erich; Pryce, Christopher R; Van De Ville, Dimitri; Rudin, Markus

    2017-03-14

    Functional connectivity (FC) derived from resting-state functional magnetic resonance imaging (rs-fMRI) allows for the integrative study of neuronal processes at a macroscopic level. The majority of studies to date have assumed stationary interactions between brain regions, without considering the dynamic aspects of network organization. Only recently has the latter received increased attention, predominantly in human studies. Applying dynamic FC (dFC) analysis to mice is attractive given the relative simplicity of the mouse brain and the possibility to explore mechanisms underlying network dynamics using pharmacological, environmental or genetic interventions. Therefore, we have evaluated the feasibility and research potential of mouse dFC using the interventions of social stress or anesthesia duration as two case-study examples. By combining a sliding-window correlation approach with dictionary learning, several dynamic functional states (dFS) with a complex organization were identified, exhibiting highly dynamic inter- and intra-modular interactions. Each dFS displayed a high degree of reproducibility upon changes in analytical parameters and across datasets. They fluctuated at different degrees as a function of anesthetic depth, and were sensitive indicators of pathology as shown for the chronic psychosocial stress mouse model of depression. Dynamic functional states are proposed to make a major contribution to information integration and processing in the healthy and diseased brain.

  18. A translational systems biology approach in both animals and humans identifies a functionally related module of accumbal genes involved in the regulation of reward processing and binge drinking in males

    Science.gov (United States)

    Stacey, David; Lourdusamy, Anbarasu; Ruggeri, Barbara; Maroteaux, Matthieu; Jia, Tianye; Cattrell, Anna; Nymberg, Charlotte; Banaschewski, Tobias; Bhattacharyya, Sohinee; Band, Hamid; Barker, Gareth; Bokde, Arun; Buchel, Christian; Carvalho, Fabiana; Conrod, Patricia; Desrivieres, Sylvane; Easton, Alanna; Fauth-Buehler, Mira; Fernandez-Medarde, Alberto; Flor, Herta; Frouin, Vincent; Gallinat, Jurgen; Garavanh, Hugh; Heinz, Andreas; Ittermann, Bernd; Lathrop, Mark; Lawrence, Claire; Loth, Eva; Mann, Karl; Martinot, Jean-Luc; Nees, Frauke; Paus, Tomas; Pausova, Zdenka; Rietschel, Marcella; Rotter, Andrea; Santos, Eugenio; Smolka, Michael; Sommer, Wolfgang; Mameli, Manuel; Spanagel, Rainer; Girault, Jean-Antoine; Mueller, Christian; Schumann, Gunter

    2016-01-01

    Background The mesolimbic dopamine system, composed primarily of dopaminergic neurons in the ventral tegmental area that project to striatal structures, is considered to be the key mediator of reinforcement-related mechanisms in the brain. Prompted by a genome-wide association meta-analysis implicating the Ras-specific guanine nucleotide-releasing factor 2 (RASGRF2) gene in the regulation of alcohol intake in men, we have recently shown that male Rasgrf2−/− mice exhibit reduced ethanol intake and preference accompanied by a perturbed mesolimbic dopamine system. We therefore propose that these mice represent a valid model to further elucidate the precise genes and mechanisms regulating mesolimbic dopamine functioning. Methods Transcriptomic data from the nucleus accumbens (NAcc) of male Rasgrf2−/− mice and wild-type controls were analyzed by weighted gene coexpression network analysis (WGCNA). We performed follow-up genetic association tests in humans using a sample of male adolescents from the IMAGEN study characterized for binge drinking (n = 905) and ventral striatal activation during an fMRI reward task (n = 608). Results The WGCNA analyses using accumbal transcriptomic data revealed 37 distinct “modules,” or functionally related groups of genes. Two of these modules were significantly associated with Rasgrf2 knockout status: M5 (p < 0.001) and M6 (p < 0.001). In follow-up translational analyses we found that human orthologues for the M5 module were significantly (p < 0.01) enriched with genetic association signals for binge drinking in male adolescents. Furthermore, the most significant locus, originating from the EH-domain containing 4 (EHD4) gene (p < 0.001), was also significantly associated with altered ventral striatal activity in male adolescents performing an fMRI reward task (pempirical < 0.001). Limitations It was not possible to determine the extent to which the M5 module was dysregulated in Rasgrf2−/− mice by perturbed mesolimbic

  19. Biological substrates of reward and aversion: a nucleus accumbens activity hypothesis.

    Science.gov (United States)

    Carlezon, William A; Thomas, Mark J

    2009-01-01

    The nucleus accumbens (NAc) is a critical element of the mesocorticolimbic system, a brain circuit implicated in reward and motivation. This basal forebrain structure receives dopamine (DA) input from the ventral tegmental area (VTA) and glutamate (GLU) input from regions including the prefrontal cortex (PFC), amygdala (AMG), and hippocampus (HIP). As such, it integrates inputs from limbic and cortical regions, linking motivation with action. The NAc has a well-established role in mediating the rewarding effects of drugs of abuse and natural rewards such as food and sexual behavior. However, accumulating pharmacological, molecular, and electrophysiological evidence has raised the possibility that it also plays an important (and sometimes underappreciated) role in mediating aversive states. Here we review evidence that rewarding and aversive states are encoded in the activity of NAc medium spiny GABAergic neurons, which account for the vast majority of the neurons in this region. While admittedly simple, this working hypothesis is testable using combinations of available and emerging technologies, including electrophysiology, genetic engineering, and functional brain imaging. A deeper understanding of the basic neurobiology of mood states will facilitate the development of well-tolerated medications that treat and prevent addiction and other conditions (e.g., mood disorders) associated with dysregulation of brain motivation systems.

  20. Meta-analysis of functional brain imaging in specific phobia.

    Science.gov (United States)

    Ipser, Jonathan C; Singh, Leesha; Stein, Dan J

    2013-07-01

    Although specific phobia is a prevalent anxiety disorder, evidence regarding its underlying functional neuroanatomy is inconsistent. A meta-analysis was undertaken to identify brain regions that were consistently responsive to phobic stimuli, and to characterize changes in brain activation following cognitive behavioral therapy (CBT). We searched the PubMed, SCOPUS and PsycINFO databases to identify positron emission tomography and functional magnetic resonance imaging studies comparing brain activation in specific phobia patients and healthy controls. Two raters independently extracted study data from all the eligible studies, and pooled coordinates from these studies using activation likelihood estimation, a quantitative meta-analytic technique. Resulting statistical parametric maps were compared between patients and healthy controls, in response to phobic versus fear-evoking stimuli, and before and after therapy. Thirteen studies were included, comprising 327 participants. Regions that were consistently activated in response to phobic stimuli included the left insula, amygdala, and globus pallidus. Compared to healthy controls, phobic subjects had increased activation in response to phobic stimuli in the left amygdala/globus pallidus, left insula, right thalamus (pulvinar), and cerebellum. Following exposure-based therapy widespread deactivation was observed in the right frontal cortex, limbic cortex, basal ganglia and cerebellum, with increased activation detected in the thalamus. Exposure to phobia-specific stimuli elicits brain activation that is consistent with current understandings of the neuroanatomy of fear conditioning and extinction. There is evidence that the effects of CBT in specific phobia may be mediated through the same underlying neurocircuitry.

  1. Practice induces function-specific changes in brain activity.

    Directory of Open Access Journals (Sweden)

    Tamar R van Raalten

    Full Text Available BACKGROUND: Practice can have a profound effect on performance and brain activity, especially if a task can be automated. Tasks that allow for automatization typically involve repeated encoding of information that is paired with a constant response. Much remains unknown about the effects of practice on encoding and response selection in an automated task. METHODOLOGY: To investigate function-specific effects of automatization we employed a variant of a Sternberg task with optimized separation of activity associated with encoding and response selection by means of m-sequences. This optimized randomized event-related design allows for model free measurement of BOLD signals over the course of practice. Brain activity was measured at six consecutive runs of practice and compared to brain activity in a novel task. PRINCIPAL FINDINGS: Prompt reductions were found in the entire cortical network involved in encoding after a single run of practice. Changes in the network associated with response selection were less robust and were present only after the third run of practice. CONCLUSIONS/SIGNIFICANCE: This study shows that automatization causes heterogeneous decreases in brain activity across functional regions that do not strictly track performance improvement. This suggests that cognitive performance is supported by a dynamic allocation of multiple resources in a distributed network. Our findings may bear importance in understanding the role of automatization in complex cognitive performance, as increased encoding efficiency in early stages of practice possibly increases the capacity to otherwise interfering information.

  2. Functional bitter taste receptors are expressed in brain cells.

    Science.gov (United States)

    Singh, Nisha; Vrontakis, Maria; Parkinson, Fiona; Chelikani, Prashen

    2011-03-04

    Humans are capable of sensing five basic tastes which are sweet, sour, salt, umami and bitter. Of these, bitter taste perception provides protection against ingestion of potentially toxic substances. Bitter taste is sensed by bitter taste receptors (T2Rs) that belong to the G-protein coupled receptors (GPCRs) superfamily. Humans have 25 T2Rs that are expressed in the oral cavity, gastrointestinal (GI) neuroendocrine cells and airway cells. Electrophysiological studies of the brain neurons show that the neurons are able to respond to different tastants. However, the presence of bitter taste receptors in brain cells has not been elucidated. In this report using RT-PCR, and immunohistochemistry analysis we show that T2Rs are expressed in multiple regions of the rat brain. RT-PCR analysis revealed the presence of T2R4, T2R107 and T2R38 transcripts in the brain stem, cerebellum, cortex and nucleus accumbens. The bitter receptor T2R4 was selected for further analysis at the transcript level by quantitative real time PCR and at the protein level by immunohistochemistry. To elucidate if the T2R4 expressed in these cells is functional, assays involving G-protein mediated calcium signaling were carried out. The functional assays showed an increase in intracellular calcium levels after the application of exogenous ligands for T2R4, denatonium benzoate and quinine to these cultured cells, suggesting that endogenous T2R4 expressed in these cells is functional. We discuss our results in terms of the physiological relevance of bitter receptor expression in the brain.

  3. Intestinal barrier function and the brain-gut axis.

    Science.gov (United States)

    Alonso, Carmen; Vicario, María; Pigrau, Marc; Lobo, Beatriz; Santos, Javier

    2014-01-01

    The luminal-mucosal interface of the intestinal tract is the first relevant location where microorganism-derived antigens and all other potentially immunogenic particles face the scrutiny of the powerful mammalian immune system. Upon regular functioning conditions, the intestinal barrier is able to effectively prevent most environmental and external antigens to interact openly with the numerous and versatile elements that compose the mucosal-associated immune system. This evolutionary super system is capable of processing an astonishing amount of antigens and non-immunogenic particles, approximately 100 tons in one individual lifetime, only considering food-derived components. Most important, to develop oral tolerance and proper active immune responses needed to prevent disease and inflammation, this giant immunogenic load has to be managed in a way that physiological inflammatory balance is constantly preserved. Adequate functioning of the intestinal barrier involves local and distant regulatory networks integrating the so-called brain-gut axis. Along this complex axis both brain and gut structures participate in the processing and execution of response signals to external and internal changes coming from the digestive tract, using multidirectional pathways to communicate. Dysfunction of brain-gut axis facilitates malfunctioning of the intestinal barrier, and vice versa, increasing the risk of uncontrolled immunological reactions that may trigger mucosal and brain low-grade inflammation, a putative first step to the initiation of more permanent gut disorders. In this chapter, we describe the structure, function and interactions of intestinal barrier, microbiota and brain-gut axis in both healthy and pathological conditions.

  4. Impaired learning of social compared to monetary rewards in autism

    Directory of Open Access Journals (Sweden)

    Alice eLin

    2012-10-01

    Full Text Available A leading hypothesis to explain the social dysfunction in people with autism spectrum disorders (ASD is that they exhibit a deficit in reward processing and motivation specific to social stimuli.  However, there have been few direct tests of this hypothesis to date.  Here we used an instrumental reward learning task that contrasted learning with social rewards (pictures of positive and negative faces against learning with monetary reward (winning and losing money. The two tasks were structurally identical except for the type of reward, permitting direct comparisons.  We tested ten high-functioning people with ASD (7M, 3F and ten healthy controls who were matched on gender, age and education.  We found no significant differences between the two groups in terms of overall ability behaviorally to discriminate positive from negative slot machines, reaction-times, and valence ratings,  However, there was a specific impairment in the ASD group in learning to choose social rewards, compared to monetary rewards: they had a significantly lower cumulative number of choices of the most rewarding social slot machine, and had a significantly slower initial learning rate for the socially rewarding slot machine, compared to the controls.  The findings show a deficit in reward learning in ASD that is greater for social rewards than for monetary rewards, and support the hypothesis of a disproportionate impairment in social reward processing in ASD.

  5. Précis of The brain and emotion.

    Science.gov (United States)

    Rolls, E T

    2000-04-01

    The topics treated in The brain and emotion include the definition, nature, and functions of emotion (Ch. 3); the neural bases of emotion (Ch. 4); reward, punishment, and emotion in brain design (Ch. 10); a theory of consciousness and its application to understanding emotion and pleasure (Ch. 9); and neural networks and emotion-related learning (Appendix). The approach is that emotions can be considered as states elicited by reinforcers (rewards and punishers). This approach helps with understanding the functions of emotion, with classifying different emotions, and in understanding what information-processing systems in the brain are involved in emotion, and how they are involved. The hypothesis is developed that brains are designed around reward- and punishment-evaluation systems, because this is the way that genes can build a complex system that will produce appropriate but flexible behavior to increase fitness (Ch. 10). By specifying goals rather than particular behavioral patterns of responses, genes leave much more open the possible behavioral strategies that might be required to increase fitness. The importance of reward and punishment systems in brain design also provides a basis for understanding the brain mechanisms of motivation, as described in Chapters 2 for appetite and feeding, 5 for brain-stimulation reward, 6 for addiction, 7 for thirst, and 8 for sexual behavior.

  6. Just watching the game ain’t enough: Striatal fMRI reward responses to successes and failures in a video game during active and vicarious playing

    Directory of Open Access Journals (Sweden)

    Jari eKätsyri

    2013-06-01

    Full Text Available Although the multimodal stimulation provided by modern audiovisual video games is pleasing by itself, the rewarding nature of video game playing depends critically also on the players’ active engagement in the gameplay. The extent to which active engagement influences dopaminergic brain reward circuit responses remains unsettled. Here we show that striatal reward circuit responses elicited by successes (wins and failures (losses in a video game are stronger during active than vicarious gameplay. Eleven healthy males both played a competitive first-person tank shooter game (active playing and watched a pre-recorded gameplay video (vicarious playing while their hemodynamic brain activation was measured with 3-tesla functional magnetic resonance imaging (fMRI. Wins and losses were paired with symmetrical monetary rewards and punishments during active and vicarious playing so that the external reward context remained identical during both conditions. Brain activation was stronger in the orbitomedial prefrontal cortex (omPFC during winning than losing, both during active and vicarious playing conditions. In contrast, both wins and losses suppressed activations in the midbrain and striatum during active playing; however, the striatal suppression, particularly in the anterior putamen, was more pronounced during loss than win events. Sensorimotor confounds related to joystick movements did not account for the results. Self-ratings indicated losing to be more unpleasant during active than vicarious playing. Our findings demonstrate striatum to be selectively sensitive to self-acquired rewards, in contrast to frontal components of the reward circuit that process both self-acquired and passively received rewards. We propose that the striatal responses to repeated acquisition of rewards that are contingent on game related successes contribute to the motivational pull of video-game playing.

  7. Forebrain substrates of reward and motivation.

    Science.gov (United States)

    Wise, Roy A

    2005-12-01

    Electrical stimulation of the medial forebrain bundle can reward arbitrary acts or motivate biologically primitive, species-typical behaviors like feeding or copulation. The subsystems involved in these behaviors are only partially characterized, but they appear to transsynaptically activate the mesocorticolimbic dopamine system. Basal function of the dopamine system is essential for arousal and motor function; phasic activation of this system is rewarding and can potentiate the effectiveness of reward-predictors that guide learned behaviors. This system is phasically activated by most drugs of abuse and such activation contributes to the habit-forming actions of these drugs.

  8. Large-Scale Functional Brain Network Abnormalities in Alzheimer’s Disease: Insights from Functional Neuroimaging

    Directory of Open Access Journals (Sweden)

    Bradford C. Dickerson

    2009-01-01

    Full Text Available Functional MRI (fMRI studies of mild cognitive impairment (MCI and Alzheimer’s disease (AD have begun to reveal abnormalities in large-scale memory and cognitive brain networks. Since the medial temporal lobe (MTL memory system is a site of very early pathology in AD, a number of studies have focused on this region of the brain. Yet it is clear that other regions of the large-scale episodic memory network are affected early in the disease as well, and fMRI has begun to illuminate functional abnormalities in frontal, temporal, and parietal cortices as well in MCI and AD. Besides predictable hypoactivation of brain regions as they accrue pathology and undergo atrophy, there are also areas of hyperactivation in brain memory and cognitive circuits, possibly representing attempted compensatory activity. Recent fMRI data in MCI and AD are beginning to reveal relationships between abnormalities of functional activity in the MTL memory system and in functionally connected brain regions, such as the precuneus. Additional work with “resting state” fMRI data is illuminating functional-anatomic brain circuits and their disruption by disease. As this work continues to mature, it will likely contribute to our understanding of fundamental memory processes in the human brain and how these are perturbed in memory disorders. We hope these insights will translate into the incorporation of measures of task-related brain function into diagnostic assessment or therapeutic monitoring, which will hopefully one day be useful for demonstrating beneficial effects of treatments being tested in clinical trials.

  9. Individual differences in sensitivity to reward and punishment and neural activity during reward and avoidance learning.

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    Kim, Sang Hee; Yoon, HeungSik; Kim, Hackjin; Hamann, Stephan

    2015-09-01

    In this functional neuroimaging study, we investigated neural activations during the process of learning to gain monetary rewards and to avoid monetary loss, and how these activations are modulated by individual differences in reward and punishment sensitivity. Healthy young volunteers performed a reinforcement learning task where they chose one of two fractal stimuli associated with monetary gain (reward trials) or avoidance of monetary loss (avoidance trials). Trait sensitivity to reward and punishment was assessed using the behavioral inhibition/activation scales (BIS/BAS). Functional neuroimaging results showed activation of the striatum during the anticipation and reception periods of reward trials. During avoidance trials, activation of the dorsal striatum and prefrontal regions was found. As expected, individual differences in reward sensitivity were positively associated with activation in the left and right ventral striatum during reward reception. Individual differences in sensitivity to punishment were negatively associated with activation in the left dorsal striatum during avoidance anticipation and also with activation in the right lateral orbitofrontal cortex during receiving monetary loss. These results suggest that learning to attain reward and learning to avoid loss are dependent on separable sets of neural regions whose activity is modulated by trait sensitivity to reward or punishment.

  10. Control channels in the brain and their influence on brain executive functions

    Science.gov (United States)

    Meng, Qinglei; Choa, Fow-Sen; Hong, Elliot; Wang, Zhiguang; Islam, Mohammad

    2014-05-01

    In a computer network there are distinct data channels and control channels where massive amount of visual information are transported through data channels but the information streams are routed and controlled by intelligent algorithm through "control channels". Recent studies on cognition and consciousness have shown that the brain control channels are closely related to the brainwave beta (14-40 Hz) and alpha (7-13 Hz) oscillations. The high-beta wave is used by brain to synchronize local neural activities and the alpha oscillation is for desynchronization. When two sensory inputs are simultaneously presented to a person, the high-beta is used to select one of the inputs and the alpha is used to deselect the other so that only one input will get the attention. In this work we demonstrated that we can scan a person's brain using binaural beats technique and identify the individual's preferred control channels. The identified control channels can then be used to influence the subject's brain executive functions. In the experiment, an EEG measurement system was used to record and identify a subject's control channels. After these channels were identified, the subject was asked to do Stroop tests. Binaural beats was again used to produce these control-channel frequencies on the subject's brain when we recorded the completion time of each test. We found that the high-beta signal indeed speeded up the subject's executive function performance and reduced the time to complete incongruent tests, while the alpha signal didn't seem to be able to slow down the executive function performance.

  11. Control of brain development, function, and behavior by the microbiome.

    Science.gov (United States)

    Sampson, Timothy R; Mazmanian, Sarkis K

    2015-05-13

    Animals share an intimate and life-long partnership with a myriad of resident microbial species, collectively referred to as the microbiota. Symbiotic microbes have been shown to regulate nutrition and metabolism and are critical for the development and function of the immune system. More recently, studies have suggested that gut bacteria can impact neurological outcomes--altering behavior and potentially affecting the onset and/or severity of nervous system disorders. In this review, we highlight emerging evidence that the microbiome extends its influence to the brain via various pathways connecting the gut to the central nervous system. While understanding and appreciation of a gut microbial impact on neurological function is nascent, unraveling gut-microbiome-brain connections holds the promise of transforming the neurosciences and revealing potentially novel etiologies for psychiatric and neurodegenerative disorders.

  12. piRNAs and Their Functions in the Brain

    Science.gov (United States)

    Zuo, Lingjun; Wang, Zhiren; Tan, Yunlong; Chen, Xiangning; Luo, Xingguang

    2016-01-01

    Piwi-interacting RNAs (piRNAs) are the non-coding RNAs with 24–32 nucleotides (nt). They exhibit stark differences in length, expression pattern, abundance, and genomic organization when compared to micro-RNAs (miRNAs). There are hundreds of thousands unique piRNA sequences in each species. Numerous piRNAs have been identified and deposited in public databases. Since the piRNAs were originally discovered and well-studied in the germline, a few other studies have reported the presence of piRNAs in somatic cells including neurons. This paper reviewed the common features, biogenesis, functions, and distributions of piRNAs and summarized their specific functions in the brain. This review may provide new insights and research direction for brain disorders. PMID:27512315

  13. Alterations of Blood Brain Barrier Function in Hyperammonemia: An Overview

    OpenAIRE

    2011-01-01

    Ammonia is a neurotoxin involved in the pathogenesis of neurological conditions associated with hyperammonemia, including hepatic encephalopathy, a condition associated with acute—(ALF) or chronic liver failure. This article reviews evidence that apart from directly affecting the metabolism and function of the central nervous system cells, ammonia influences the passage of different molecules across the blood brain barrier (BBB). A brief description is provided of the tight junctions, which c...

  14. Impact of early life adversity on reward processing in young adults: EEG-fMRI results from a prospective study over 25 years.

    Directory of Open Access Journals (Sweden)

    Regina Boecker

    Full Text Available Several lines of evidence have implicated the mesolimbic dopamine reward pathway in altered brain function resulting from exposure to early adversity. The present study examined the impact of early life adversity on different stages of neuronal reward processing later in life and their association with a related behavioral phenotype, i.e. attention deficit/hyperactivity disorder (ADHD. 162 healthy young adults (mean age = 24.4 years; 58% female from an epidemiological cohort study followed since birth participated in a simultaneous EEG-fMRI study using a monetary incentive delay task. Early life adversity according to an early family adversity index (EFA and lifetime ADHD symptoms were assessed using standardized parent interviews conducted at the offspring's age of 3 months and between 2 and 15 years, respectively. fMRI region-of-interest analysis revealed a significant effect of EFA during reward anticipation in reward-related areas (i.e. ventral striatum, putamen, thalamus, indicating decreased activation when EFA increased. EEG analysis demonstrated a similar effect for the contingent negative variation (CNV, with the CNV decreasing with the level of EFA. In contrast, during reward delivery, activation of the bilateral insula, right pallidum and bilateral putamen increased with EFA. There was a significant association of lifetime ADHD symptoms with lower activation in the left ventral striatum during reward anticipation and higher activation in the right insula during reward delivery. The present findings indicate a differential long-term impact of early life adversity on reward processing, implicating hyporesponsiveness during reward anticipation and hyperresponsiveness when receiving a reward. Moreover, a similar activation pattern related to lifetime ADHD suggests that the impact of early life stress on ADHD may possibly be mediated by a dysfunctional reward pathway.

  15. Link Between Increased Satiety Gut Hormones and Reduced Food Reward After Gastric Bypass Surgery for Obesity

    Science.gov (United States)

    Miras, Alexander D.; Scholtz, Samantha; Jackson, Sabrina; Neff, Karl J.; Pénicaud, Luc; Geoghegan, Justin; Chhina, Navpreet; Durighel, Giuliana; Bell, Jimmy D.; Meillon, Sophie; le Roux, Carel W.

    2016-01-01

    Context: Roux-en-Y gastric bypass (RYGB) surgery is an effective long-term intervention for weight loss maintenance, reducing appetite, and also food reward, via unclear mechanisms. Objective: To investigate the role of elevated satiety gut hormones after RYGB, we examined food hedonic-reward responses after their acute post-prandial suppression. Design: These were randomized, placebo-controlled, double-blind, crossover experimental medicine studies. Patients: Two groups, more than 5 months after RYGB for obesity (n = 7–11), compared with nonobese controls (n = 10), or patients after gastric banding (BAND) surgery (n = 9) participated in the studies. Intervention: Studies were performed after acute administration of the somatostatin analog octreotide or saline. In one study, patients after RYGB, and nonobese controls, performed a behavioral progressive ratio task for chocolate sweets. In another study, patients after RYGB, and controls after BAND surgery, performed a functional magnetic resonance imaging food picture evaluation task. Main Outcome Measures: Octreotide increased both appetitive food reward (breakpoint) in the progressive ratio task (n = 9), and food appeal (n = 9) and reward system blood oxygen level-dependent signal (n = 7) in the functional magnetic resonance imaging task, in the RYGB group, but not in the control groups. Results: Octreotide suppressed postprandial plasma peptide YY, glucagon-like peptide-1, and fibroblast growth factor-19 after RYGB. The reduction in plasma peptide YY with octreotide positively correlated with the increase in brain reward system blood oxygen level-dependent signal in RYGB/BAND subjects, with a similar trend for glucagon-like peptide-1. Conclusions: Enhanced satiety gut hormone responses after RYGB may be a causative mechanism by which anatomical alterations of the gut in obesity surgery modify behavioral and brain reward responses to food. PMID:26580235

  16. Rescue of Brain Function Using Tunneling Nanotubes Between Neural Stem Cells and Brain Microvascular Endothelial Cells.

    Science.gov (United States)

    Wang, Xiaoqing; Yu, Xiaowen; Xie, Chong; Tan, Zijian; Tian, Qi; Zhu, Desheng; Liu, Mingyuan; Guan, Yangtai

    2016-05-01

    Evidence indicates that neural stem cells (NSCs) can ameliorate cerebral ischemia in animal models. In this study, we investigated the mechanism underlying one of the neuroprotective effects of NSCs: tunneling nanotube (TNT) formation. We addressed whether the control of cell-to-cell communication processes between NSCs and brain microvascular endothelial cells (BMECs) and, particularly, the control of TNT formation could influence the rescue function of stem cells. In an attempt to mimic the cellular microenvironment in vitro, a co-culture system consisting of terminally differentiated BMECs from mice in a distressed state and NSCs was constructed. Additionally, engraftment experiments with infarcted mouse brains revealed that control of TNT formation influenced the effects of stem cell transplantation in vivo. In conclusion, our findings provide the first evidence that TNTs exist between NSCs and BMECs and that regulation of TNT formation alters cell function.

  17. Treatment-related changes in functional connectivity in brain tumor patients : a magnetoencephalography study

    NARCIS (Netherlands)

    Douw, Linda; Baayen, Hans; Bosma, Ingeborg; Klein, Martin; Vandertop, Peter; Heimans, Jan; Stam, Kees; de Munck, Jan; Reijneveld, Jaap

    2008-01-01

    Widespread disturbances in resting state functional connectivity between remote brain areas have been demonstrated in patients with brain tumors. Functional connectivity has been associated with neurocognitive deficits in these patients. Thus far, it is unknown how (surgical) treatment affects funct

  18. Barrier Functionality of Porcine and Bovine Brain Capillary Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Ailar Nakhlband

    2011-09-01

    Full Text Available Introduction: To date, isolated cell based blood-brain barrier (BBB models have been widely used for brain drug delivery and targeting, due to their relatively proper bioelectrical and permeability properties. However, primary cultures of brain capillary endothelial cells (BCECs isolated from different species vary in terms of bioelectrical and permeability properties. Methods: To pursue this, in the current investigation, primary porcine and bovine BCECs (PBCECs and BBCECs, respectively were isolated and used as an in vitro BBB model. The bioelectrical and permeability properties were assessed in BCECs co-cultured with C6 cells with/without hydrocortisone (550 nM. The bioelectrical properties were further validated by means of the permeability coefficients of transcellular and paracellular markers. Results: The primary PBCECs displayed significantly higher trans-endothelial electrical resistance (~900 W.cm2 than BBCECs (~700 W.cm2 - both co-cultured with C6 cells in presence of hydrocortisone. Permeability coefficients of propranolol/diazepam and mannitol/sucrose in PBCECs were ~21 and ~2 (×10-6 cm.sec-1, where these values for BBCECs were ~25 and ~5 (×10-6 cm.sec-1. Conclusion: Upon our bioelectrical and permeability findings, both models display discriminative barrier functionality but porcine BCECs seem to provide a better platform than bovine BCECs for drug screening and brain targeting.

  19. Effects of exercise on brain functions in diabetic animalmodels

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Human life span has dramatically increased overseveral decades, and the quality of life has beenconsidered to be equally important. However, diabetesmellitus (DM) characterized by problems relatedto insulin secretion and recognition has become aserious health problem in recent years that threatenshuman health by causing decline in brain functionsand finally leading to neurodegenerative diseases.Exercise is recognized as an effective therapy for DMwithout medication administration. Exercise studiesusing experimental animals are a suitable option toovercome this drawback, and animal studies haveimproved continuously according to the needs of theexperimenters. Since brain health is the most significantfactor in human life, it is very important to assess brainfunctions according to the different exercise conditionsusing experimental animal models. Generally, thereare two types of DM; insulin-dependent type 1 DM andan insulin-independent type 2 DM (T2DM); however,the author will mostly discuss brain functions in T2DManimal models in this review. Additionally, many physiopathologicalterations are caused in the brain by DMsuch as increased adiposity, inflammation, hormonaldysregulation, uncontrolled hyperphagia, insulin andleptin resistance, and dysregulation of neurotransmittersand declined neurogenesis in the hippocampus andwe describe how exercise corrects these alterationsin animal models. The results of changes in the brainenvironment differ according to voluntary, involuntaryrunning exercises and resistance exercise, and gender inthe animal studies. These factors have been mentionedin this review, and this review will be a good referencefor studying how exercise can be used with therapy fortreating DM.

  20. Brain Oscillations and Functional Connectivity during Overt Language Production.

    Science.gov (United States)

    Ewald, Arne; Aristei, Sabrina; Nolte, Guido; Abdel Rahman, Rasha

    2012-01-01

    In the present study we investigate the communication of different large scale brain sites during an overt language production task with state of the art methods for the estimation of EEG functional connectivity. Participants performed a semantic blocking task in which objects were named in semantically homogeneous blocks of trials consisting of members of a semantic category (e.g., all objects are tools) or in heterogeneous blocks, consisting of unrelated objects. The classic pattern of slower naming times in the homogeneous relative to heterogeneous blocks is assumed to reflect the duration of lexical selection. For the collected data in the homogeneous and heterogeneous conditions the imaginary part of coherency (ImC) was evaluated at different frequencies. The ImC is a measure for detecting the coupling of different brain sites acting on sensor level. Most importantly, the ImC is robust to the artifact of volume conduction. We analyzed the ImC at all pairs of 56 EEG channels across all frequencies. Contrasting the two experimental conditions we found pronounced differences in the theta band at 7 Hz and estimated the most dominant underlying brain sources via a minimum norm inverse solution based on the ImC. As a result of the source localization, we observed connectivity between occipito-temporal and frontal areas, which are well-known to play a major role in lexical-semantic language processes. Our findings demonstrate the feasibility of investigating interactive brain activity during overt language production.

  1. Functional Specialization within the Striatum along Both the Dorsal/Ventral and Anterior/Posterior Axes during Associative Learning via Reward and Punishment

    Science.gov (United States)

    Mattfeld, Aaron T.; Gluck, Mark A.; Stark, Craig E. L.

    2011-01-01

    The goal of the present study was to elucidate the role of the human striatum in learning via reward and punishment during an associative learning task. Previous studies have identified the striatum as a critical component in the neural circuitry of reward-related learning. It remains unclear, however, under what task conditions, and to what…

  2. Functional magnetic resonance imaging of the brain: A quick review

    Directory of Open Access Journals (Sweden)

    Vaghela Viratsinh

    2010-01-01

    Full Text Available Ability to non-invasively map the hemodynamic changes occurring focally in areas of brain involved in various motor, sensory and cognitive functions by functional magnetic resonance imaging (fMRI has revolutionized research in neuroscience in the last two decades. This technique has already gained clinical use especially in pre-surgical evaluation of epilepsy and neurosurgical planning of resection of mass lesions adjacent to eloquent cortex. In this review we attempt to illustrate basic principles and techniques of fMRI, its applications, practical points to consider while performing and evaluating clinical fMRI and its limitations.

  3. Leptin action in the midbrain: From reward to stress.

    Science.gov (United States)

    Xu, Lu

    2014-11-01

    The midbrain is a heterogenous brain structure that serves important roles in feeding regulation, motivation and reward, movement and stress adaptation. One common feature of different midbrain regions is that they all express the long form of leptin receptor (LepRb). Leptin is mainly produced and secreted by white adipose tissue, informing the brain centers via LepRb about the amount of fat storage in the body. In this way, leptin exerts its action in the midbrain to regulate different functions. First, this review deals with the basic information of leptin and its signaling. Then, attention is given to various interactions of leptin with the midbrain regions, including ventral tegmental area (VTA), substantia nigra pars compacta (SNc), rostral linear raphe (RLi) and centrally-projecting Edinger-Westphal nucleus (EWcp). Also, the projection areas of these midbrain regions are discussed. Finally, the possible function of leptin in the midbrain is suggested.

  4. The human orbitofrontal cortex: linking reward to hedonic experience.

    Science.gov (United States)

    Kringelbach, Morten L

    2005-09-01

    Hedonic experience is arguably at the heart of what makes us human. In recent neuroimaging studies of the cortical networks that mediate hedonic experience in the human brain, the orbitofrontal cortex has emerged as the strongest candidate for linking food and other types of reward to hedonic experience. The orbitofrontal cortex is among the least understood regions of the human brain, but has been proposed to be involved in sensory integration, in representing the affective value of reinforcers, and in decision making and expectation. Here, the functional neuroanatomy of the human orbitofrontal cortex is described and a new integrated model of its functions proposed, including a possible role in the mediation of hedonic experience.

  5. Investigating the Impact of a Genome-Wide Supported Bipolar Risk Variant of MAD1L1 on the Human Reward System.

    Science.gov (United States)

    Trost, Sarah; Diekhof, Esther K; Mohr, Holger; Vieker, Henning; Krämer, Bernd; Wolf, Claudia; Keil, Maria; Dechent, Peter; Binder, Elisabeth B; Gruber, Oliver

    2016-10-01

    Recent genome-wide association studies have identified MAD1L1 (mitotic arrest deficient-like 1) as a susceptibility gene for bipolar disorder and schizophrenia. The minor allele of the single-nucleotide polymorphism (SNP) rs11764590 in MAD1L1 was associated with bipolar disorder. Both diseases, bipolar disorder and schizophrenia, are linked to functional alterations in the reward system. We aimed at investigating possible effects of the MAD1L1 rs11764590 risk allele on reward systems functioning in healthy adults. A large homogenous sample of 224 young (aged 18-31 years) participants was genotyped and underwent functional magnetic resonance imaging (fMRI). All participants performed the 'Desire-Reason Dilemma' paradigm investigating the neural correlates that underlie reward processing and active reward dismissal in favor of a long-term goal. We found significant hypoactivations of the ventral tegmental area (VTA), the bilateral striatum and bilateral frontal and parietal cortices in response to conditioned reward stimuli in the risk allele carriers compared with major allele carriers. In the dilemma situation, functional connectivity between prefrontal brain regions and the ventral striatum was significantly diminished in the risk allele carriers. Healthy risk allele carriers showed a significant deficit of their bottom-up response to conditioned reward stimuli in the bilateral VTA and striatum. Furthermore, functional connectivity between the ventral striatum and prefrontal areas exerting top-down control on the mesolimbic reward system was reduced in this group. Similar alterations in reward processing and disturbances of prefrontal control mechanisms on mesolimbic brain circuits have also been reported in bipolar disorder and schizophrenia. Together, these findings suggest the existence of an intermediate phenotype associated with MAD1L1.

  6. Prior fear conditioning and reward learning interact in fear and reward networks

    Directory of Open Access Journals (Sweden)

    Lisa eBulganin

    2014-03-01

    Full Text Available The ability to flexibly adapt responses to changes in the environment is important for survival. Previous research in humans separately examined the mechanisms underlying acquisition and extinction of aversive and appetitive conditioned responses. It is yet unclear how aversive and appetitive learning interact on a neural level during counterconditioning in humans. This functional magnetic resonance imaging (fMRI study investigated the interaction of fear conditioning and subsequent reward learning. In the first phase (fear acquisition, images predicted aversive electric shocks or no aversive outcome. In the second phase (counterconditioning, half of the CS+ and CS- were associated with monetary reward in the absence of electric stimulation. The third phase initiated reinstatement of fear through presentation of electric shocks, followed by CS presentation in the absence of shock or reward. Results indicate that participants were impaired at learning the reward contingencies for stimuli previously associated with shock. In the counterconditioning phase, prior fear association interacted with reward representation in the amygdala, where activation was decreased for rewarded compared to unrewarded CS- trials, while there was no reward-related difference in CS+ trials. In the reinstatement phase, an interaction of previous fear association and previous reward status was observed in a reward network consisting of substantia nigra / ventral tegmental area (SN/VTA, striatum and orbitofrontal cortex (OFC, where activation was increased by previous reward association only for CS- but not for CS+ trials. These findings suggest that during counterconditioning, prior fear conditioning interferes with reward learning, subsequently leading to lower activation of the reward network.

  7. New developments in brain research of internet and gaming disorder.

    Science.gov (United States)

    Weinstein, Aviv; Livny, Abigail; Weizman, Abraham

    2017-04-01

    There is evidence that the neural mechanisms underlying Internet Gaming Disorder (IGD) resemble those of drug addiction. Functional Magnetic Resonance Imaging (fMRI) studies of the resting state and measures of gray matter volume have shown that Internet game playing was associated with changes to brain regions responsible for attention and control, impulse control, motor function, emotional regulation, sensory-motor coordination. Furthermore, Internet game playing was associated with lower white matter density in brain regions that are involved in decision-making, behavioral inhibition and emotional regulation. Videogame playing involved changes in reward inhibitory mechanisms and loss of control. Structural brain imaging studies showed alterations in the volume of the ventral striatum that is an important part of the brain's reward mechanisms. Finally, videogame playing was associated with dopamine release similar in magnitude to those of drugs of abuse and lower dopamine transporter and dopamine receptor D2 occupancy indicating sub-sensitivity of dopamine reward mechanisms.

  8. Dorsomedial striatum lesions affect adjustment to reward uncertainty, but not to reward devaluation or omission.

    Science.gov (United States)

    Torres, Carmen; Glueck, Amanda C; Conrad, Shannon E; Morón, Ignacio; Papini, Mauricio R

    2016-09-22

    The dorsomedial striatum (DMS) has been implicated in the acquisition of reward representations, a proposal leading to the hypothesis that it should play a role in situations involving reward loss. We report the results of an experiment in which the effects of DMS excitotoxic lesions were tested in consummatory successive negative contrast (reward devaluation), autoshaping training with partial vs. continuous reinforcement (reward uncertainty), and appetitive extinction (reward omission). Animals with DMS lesions exhibited reduced lever pressing responding, but enhanced goal entries, during partial reinforcement training in autoshaping. However, they showed normal negative contrast, acquisition under continuous reinforcement (CR), appetitive extinction, and response facilitation in early extinction trials. Open-field testing also indicated normal motor behavior. Thus, DMS lesions selectively affected the behavioral adjustment to a situation involving reward uncertainty, producing a behavioral reorganization according to which goal tracking (goal entries) became predominant at the expense of sign tracking (lever pressing). This pattern of results shows that the function of the DMS in situations involving reward loss is not general, but restricted to reward uncertainty. We suggest that a nonassociative, drive-related process induced by reward uncertainty requires normal output from DMS neurons.

  9. Hypothalamic-Pituitary Function in Brain Death: A Review.

    Science.gov (United States)

    Nair-Collins, Michael; Northrup, Jesse; Olcese, James

    2016-01-01

    The Uniform Determination of Death Act (UDDA) states that an individual is dead when "all functions of the entire brain" have ceased irreversibly. However, it has been questioned whether some functions of the hypothalamus, particularly osmoregulation, can continue after the clinical diagnosis of brain death (BD). In order to learn whether parts of the hypothalamus can continue to function after the diagnosis of BD, we performed 2 separate systematic searches of the MEDLINE database, corresponding to the functions of the posterior and anterior pituitary. No meta-analysis is possible due to nonuniformity in the clinical literature. However, some modest generalizations can reasonably be drawn from a narrative review and from anatomic considerations that explain why these findings should be expected. We found evidence suggesting the preservation of hypothalamic function, including secretion of hypophysiotropic hormones, responsiveness to anterior pituitary stimulation, and osmoregulation, in a substantial proportion of patients declared dead by neurological criteria. We discuss several possible explanations for these findings. We conclude by suggesting that additional clinical research with strict inclusion criteria is necessary and further that a more nuanced and forthright public dialogue is needed, particularly since standard diagnostic practices and the UDDA may not be entirely in accord.

  10. Differential Effects of Brain Disorders on Structural and Functional Connectivity

    Science.gov (United States)

    Vega-Pons, Sandro; Olivetti, Emanuele; Avesani, Paolo; Dodero, Luca; Gozzi, Alessandro; Bifone, Angelo

    2017-01-01

    Different measures of brain connectivity can be defined based on neuroimaging read-outs, including structural and functional connectivity. Neurological and psychiatric conditions are often associated with abnormal connectivity, but comparing the effects of the disease on different types of connectivity remains a challenge. In this paper, we address the problem of quantifying the relative effects of brain disease on structural and functional connectivity at a group level. Within the framework of a graph representation of connectivity, we introduce a kernel two-sample test as an effective method to assess the difference between the patients and control group. Moreover, we propose a common representation space for structural and functional connectivity networks, and a novel test statistics to quantitatively assess differential effects of the disease on different types of connectivity. We apply this approach to a dataset from BTBR mice, a murine model of Agenesis of the Corpus Callosum (ACC), a congenital disorder characterized by the absence of the main bundle of fibers connecting the two hemispheres. We used normo-callosal mice (B6) as a comparator. The application of the proposed methods to this data-set shows that the two types of connectivity can be successfully used to discriminate between BTBR and B6, meaning that both types of connectivity are affected by ACC. However, our novel test statistics shows that structural connectivity is significantly more affected than functional connectivity, consistent with the idea that functional connectivity has a robust topology that can tolerate substantial alterations in its structural connectivity substrate. PMID:28119556

  11. A Multivariate Granger Causality Concept towards Full Brain Functional Connectivity.

    Science.gov (United States)

    Schmidt, Christoph; Pester, Britta; Schmid-Hertel, Nicole; Witte, Herbert; Wismüller, Axel; Leistritz, Lutz

    2016-01-01

    Detecting changes of spatially high-resolution functional connectivity patterns in the brain is crucial for improving the fundamental understanding of brain function in both health and disease, yet still poses one of the biggest challenges in computational neuroscience. Currently, classical multivariate Granger Causality analyses of directed interactions between single process components in coupled systems are commonly restricted to spatially low- dimensional data, which requires a pre-selection or aggregation of time series as a preprocessing step. In this paper we propose a new fully multivariate Granger Causality approach with embedded dimension reduction that makes it possible to obtain a representation of functional connectivity for spatially high-dimensional data. The resulting functional connectivity networks may consist of several thousand vertices and thus contain more detailed information compared to connectivity networks obtained from approaches based on particular regions of interest. Our large scale Granger Causality approach is applied to synthetic and resting state fMRI data with a focus on how well network community structure, which represents a functional segmentation of the network, is preserved. It is demonstrated that a number of different community detection algorithms, which utilize a variety of algorithmic strategies and exploit topological features differently, reveal meaningful information on the underlying network module structure.

  12. A Multivariate Granger Causality Concept towards Full Brain Functional Connectivity.

    Directory of Open Access Journals (Sweden)

    Christoph Schmidt

    Full Text Available Detecting changes of spatially high-resolution functional connectivity patterns in the brain is crucial for improving the fundamental understanding of brain function in both health and disease, yet still poses one of the biggest challenges in computational neuroscience. Currently, classical multivariate Granger Causality analyses of directed interactions between single process components in coupled systems are commonly restricted to spatially low- dimensional data, which requires a pre-selection or aggregation of time series as a preprocessing step. In this paper we propose a new fully multivariate Granger Causality approach with embedded dimension reduction that makes it possible to obtain a representation of functional connectivity for spatially high-dimensional data. The resulting functional connectivity networks may consist of several thousand vertices and thus contain more detailed information compared to connectivity networks obtained from approaches based on particular regions of interest. Our large scale Granger Causality approach is applied to synthetic and resting state fMRI data with a focus on how well network community structure, which represents a functional segmentation of the network, is preserved. It is demonstrated that a number of different community detection algorithms, which utilize a variety of algorithmic strategies and exploit topological features differently, reveal meaningful information on the underlying network module structure.

  13. Abdominal Pain, the Adolescent and Altered Brain Structure and Function.

    Directory of Open Access Journals (Sweden)

    Catherine S Hubbard

    Full Text Available Irritable bowel syndrome (IBS is a functional gastrointestinal (GI disorder of unknown etiology. Although relatively common in children, how this condition affects brain structure and function in a pediatric population remains unclear. Here, we investigate brain changes in adolescents with IBS and healthy controls. Imaging was performed with a Siemens 3 Tesla Trio Tim MRI scanner equipped with a 32-channel head coil. A high-resolution T1-weighted anatomical scan was acquired followed by a T2-weighted functional scan. We used a surface-based morphometric approach along with a seed-based resting-state functional connectivity (RS-FC analysis to determine if groups differed in cortical thickness and whether areas showing structural differences also showed abnormal RS-FC patterns. Patients completed the Abdominal Pain Index and the GI Module of the Pediatric Quality of Life Inventory to assess abdominal pain severity and impact of GI symptoms on health-related quality of life (HRQOL. Disease duration and pain intensity were also assessed. Pediatric IBS patients, relative to controls, showed cortical thickening in the posterior cingulate (PCC, whereas cortical thinning in posterior parietal and prefrontal areas were found, including the dorsolateral prefrontal cortex (DLPFC. In patients, abdominal pain severity was related to cortical thickening in the intra-abdominal area of the primary somatosensory cortex (SI, whereas HRQOL was associated with insular cortical thinning. Disease severity measures correlated with cortical thickness in bilateral DLPFC and orbitofrontal cortex. Patients also showed reduced anti-correlations between PCC and DLPFC compared to controls, a finding that may reflect aberrant connectivity between default mode and cognitive control networks. We are the first to demonstrate concomitant structural and functional brain changes associated with abdominal pain severity, HRQOL related to GI-specific symptoms, and disease

  14. A new scale for measuring reward responsiveness

    Directory of Open Access Journals (Sweden)

    Ivo Van Den Berg

    2010-12-01

    Full Text Available Several psychological theories assume that there are two basic brain mechanisms that guide behavior: an avoidance or inhibition system, which is responsive to signals of punishment, and an approach or activation system, which is sensitive to signals of reward. Several self-report scales have been developed to assess the sensitivity to punishment and reward, and these instruments have been shown to be useful in research on personality, psychopathology, and underlying biological substrates. However, it is also true that in particular scales for measuring reward responsiveness suffer from various inadequacies. Therefore, a new Reward Responsiveness (RR scale was developed and subjected to an extensive psychometric evaluation. The results show that this scale measures a single factor, reward responsiveness that is clearly independent of punishment sensitivity. Further, the data indicated that the internal consistency, convergent validity, discriminant validity, test-retest reliability, and predictive properties of the new scale were all adequate. It can be concluded that the RR scale is a psychometrically sound instrument that may be useful for researchers with interest in the personality construct of reward responsiveness.

  15. Differential effects of L-tryptophan and L-leucine administration on brain resting state functional networks and plasma hormone levels

    Science.gov (United States)

    Zanchi, Davide; Meyer-Gerspach, Anne Christin; Suenderhauf, Claudia; Janach, Katharina; le Roux, Carel W.; Haller, Sven; Drewe, Jürgen; Beglinger, Christoph; Wölnerhanssen, Bettina K.; Borgwardt, Stefan

    2016-01-01

    Depending on their protein content, single meals can rapidly influence the uptake of amino acids into the brain and thereby modify brain functions. The current study investigates the effects of two different amino acids on the human gut-brain system, using a multimodal approach, integrating physiological and neuroimaging data. In a randomized, placebo-controlled trial, L-tryptophan, L-leucine, glucose and water were administered directly into the gut of 20 healthy subjects. Functional MRI (fMRI) in a resting state paradigm (RS), combined with the assessment of insulin and glucose blood concentration, was performed before and after treatment. Independent component analysis with dual regression technique was applied to RS-fMRI data. Results were corrected for multiple comparisons. In comparison to glucose and water, L-tryptophan consistently modifies the connectivity of the cingulate cortex in the default mode network, of the insula in the saliency network and of the sensory cortex in the somatosensory network. L-leucine has lesser effects on these functional networks. L-tryptophan and L-leucine also modified plasma insulin concentration. Finally, significant correlations were found between brain modifications after L-tryptophan administration and insulin plasma levels. This study shows that acute L-tryptophan and L-leucine intake directly influence the brain networks underpinning the food-reward system and appetite regulation. PMID:27760995

  16. Carbofuran Modulating Functions of Acetylcholinesterase from Rat Brain In Vitro

    Directory of Open Access Journals (Sweden)

    Vivek Kumar Gupta

    2016-01-01

    Full Text Available Carbofuran, a potential environmental xenobiotic, has the ability to cross blood brain barrier and to adversely influence brain functions. In the present study, the impact of carbofuran on the biophysical and biochemical properties of rat brain AChE has been evaluated in vitro. This enzyme was membrane-bound which could be solubilised using Triton-X100 (0.2%, v/v, a nonionic detergent, in the extraction buffer (50 mM phosphate, pH 7.4. The enzyme was highly stable up to one month when stored at -20°C and exhibited optimum activity at pH 7.4 and 37°C. AChE displayed a direct relationship between activity and varying substrate concentrations (acetylthiocholine iodide (ATI by following Michaelis-Menten curve. The Km and Vmax values as computed from the Lineweaver-Burk double reciprocal plot of the data were found to be 0.07 mM and 0.066 µmole/mL/min, respectively. The enzyme exhibited IC50 value for carbofuran equal to 6.0 nM. The steady-state kinetic studies to determine mode of action of carbofuran on rat brain AChE displayed it to be noncompetitive in nature with Ki value equal to 5 nm. These experiments suggested that rat brain AChE was very sensitive to carbofuran and this enzyme might serve as a significant biomarker of carbofuran induced neurotoxicity.

  17. Improved memory for reward cues following acute buprenorphine administration in humans

    NARCIS (Netherlands)

    Syal, Supriya; Ipser, Jonathan; Terburg, David; Solms, Mark; Panksepp, Jaak; Malcolm-Smith, Susan; Bos, Peter A.; Montoya, Estrella R.; Stein, Dan J.; van Honk, Jack

    2015-01-01

    In rodents, there is abundant evidence for the involvement of the opioid system in the processing of reward cues, but this system has remained understudied in humans. In humans, the happy facial expression is a pivotal reward cue. Happy facial expressions activate the brain's reward system and are d

  18. Anticipation of novelty recruits reward system and hippocampus while promoting recollection

    OpenAIRE

    2007-01-01

    The dopaminergic midbrain, which comprises the substantia nigra and ventral tegmental area (SN/VTA), plays a central role in reward processing. This region is also activated by novel stimuli, raising the possibility that novelty and reward have shared functional properties. It is currently unclear whether functional aspects of reward processing in the SN/VTA, namely, activation by unexpected rewards and cues that predict reward, also characterise novelty processing. To address this question, ...

  19. Brain Basics

    Medline Plus

    Full Text Available ... the brain, which is linked to thought and emotion. It is also linked to reward systems in ... or-flight response and is also involved in emotions and memory. anterior cingulate cortex —Is involved in ...

  20. Effects of Deep Brain Stimulation on Autonomic Function

    Directory of Open Access Journals (Sweden)

    Adam Basiago

    2016-08-01

    Full Text Available Over the course of the development of deep brain stimulation (DBS into a well-established therapy for Parkinson’s disease, essential tremor, and dystonia, its utility as a potential treatment for autonomic dysfunction has emerged. Dysfunction of autonomic processes is common in neurological diseases. Depending on the specific target in the brain, DBS has been shown to raise or lower blood pressure, normalize the baroreflex, to alter the caliber of bronchioles, and eliminate hyperhidrosis, all through modulation of the sympathetic nervous system. It has also been shown to improve cortical control of the bladder, directly induce or inhibit the micturition reflex, and to improve deglutition and gastric emptying. In this review, we will attempt to summarize the relevant available studies describing these effects of DBS on autonomic function, which vary greatly in character and magnitude with respect to stimulation target.

  1. Finding intrinsic rewards by embodied evolution and constrained reinforcement learning.

    Science.gov (United States)

    Uchibe, Eiji; Doya, Kenji

    2008-12-01

    Understanding the design principle of reward functions is a substantial challenge both in artificial intelligence and neuroscience. Successful acquisition of a task usually requires not only rewards for goals, but also for intermediate states to promote effective exploration. This paper proposes a method for designing 'intrinsic' rewards of autonomous agents by combining constrained policy gradient reinforcement learning and embodied evolution. To validate the method, we use Cyber Rodent robots, in which collision avoidance, recharging from battery packs, and 'mating' by software reproduction are three major 'extrinsic' rewards. We show in hardware experiments that the robots can find appropriate 'intrinsic' rewards for the vision of battery packs and other robots to promote approach behaviors.

  2. A propositional representation model of anatomical and functional brain data.

    Science.gov (United States)

    Maturana, Pablo; Batrancourt, Bénédicte

    2011-01-01

    Networks can represent a large number of systems. Recent advances in the domain of networks have been transferred to the field of neuroscience. For example, the graph model has been used in neuroscience research as a methodological tool to examine brain networks organization, topology and complex dynamics, as well as a framework to test the structure-function hypothesis using neuroimaging data. In the current work we propose a graph-theoretical framework to represent anatomical, functional and neuropsychological assessment instruments information. On the one hand, interrelationships between anatomic elements constitute an anatomical graph. On the other hand, a functional graph contains several cognitive functions and their more elementary cognitive processes. Finally, the neuropsychological assessment instruments graph includes several neuropsychological tests and scales linked with their different sub-tests and variables. The two last graphs are connected by relations of type "explore" linking a particular instrument with the cognitive function it explores. We applied this framework to a sample of patients with focal brain damage. Each patient was related to: (i) the cerebral entities injured (assessed with structural neuroimaging data) and (ii) the neusopsychological assessment tests carried out (weight by performance). Our model offers a suitable platform to visualize patients' relevant information, facilitating the representation, standardization and sharing of clinical data. At the same time, the integration of a large number of patients in this framework will make possible to explore relations between anatomy (injured entities) and function (performance in different tests assessing different cognitive functions) and the use of neurocomputational tools for graph analysis may help diagnostic and contribute to the comprehension of neural bases of cognitive functions.

  3. Selective oestrogen receptor modulators differentially potentiate brain mitochondrial function.

    Science.gov (United States)

    Irwin, R W; Yao, J; To, J; Hamilton, R T; Cadenas, E; Brinton, R D

    2012-01-01

    The mitochondrial energy-transducing capacity of the brain is important for long-term neurological health and is influenced by endocrine hormone responsiveness. The present study aimed to determine the role of oestrogen receptor (ER) subtypes in regulating mitochondrial function using selective agonists for ERα (propylpyrazoletriol; PPT) and ERβ (diarylpropionitrile; DPN). Ovariectomised female rats were treated with 17β-oestradiol (E(2) ), PPT, DPN or vehicle control. Both ER selective agonists significantly increased the mitochondrial respiratory control ratio and cytochrome oxidase (COX) activity relative to vehicle. Western blots of purified whole brain mitochondria detected ERα and, to a greater extent, ERβ localisation. Pre-treatment with DPN, an ERβ agonist, significantly increased ERβ association with mitochondria. In the hippocampus, DPN activated mitochondrial DNA-encoded COX I expression, whereas PPT was ineffective, indicating that mechanistically ERβ, and not ERα, activated mitochondrial transcriptional machinery. Both selective ER agonists increased protein expression of nuclear DNA-encoded COX IV, suggesting that activation of ERβ or ERα is sufficient. Selective ER agonists up-regulated a panel of bioenergetic enzymes and antioxidant defence proteins. Up-regulated proteins included pyruvate dehydrogenase, ATP synthase, manganese superoxide dismutase and peroxiredoxin V. In vitro, whole cell metabolism was assessed in live primary cultured hippocampal neurones and mixed glia. The results of analyses conducted in vitro were consistent with data obtained in vivo. Furthermore, lipid peroxides, accumulated as a result of hormone deprivation, were significantly reduced by E(2) , PPT and DPN. These findings suggest that the activation of both ERα and ERβ is differentially required to potentiate mitochondrial function in brain. As active components in hormone therapy, synthetically designed oestrogens as well as natural phyto-oestrogen cocktails

  4. Neuromodulation as a Robot Controller: A Brain Inspired Strategy for Controlling Autonomous Robots

    Science.gov (United States)

    2009-09-01

    risks, rewards, novelty , effort, and social cooperation. Moreover, the neuromodulatory systems provide a foundation for cognitive function in...brain areas such as the amygdala, frontal cortex, and hippocampus . Therefore, understanding neuromodulatory function may provide control and action...of the brain such as the amygdala, frontal cortex and the hippocampus [2]. 3. The effect of each of these neuromodulatory systems on downstream

  5. Totally tubular: the mystery behind function and origin of the brain ventricular system.

    Science.gov (United States)

    Lowery, Laura Anne; Sive, Hazel

    2009-04-01

    A unique feature of the vertebrate brain is the ventricular system, a series of connected cavities which are filled with cerebrospinal fluid (CSF) and surrounded by neuroepithelium. While CSF is critical for both adult brain function and embryonic brain development, neither development nor function of the brain ventricular system is fully understood. In this review, we discuss the mystery of why vertebrate brains have ventricles, and whence they originate. The brain ventricular system develops from the lumen of the neural tube, as the neuroepithelium undergoes morphogenesis. The molecular mechanisms underlying this ontogeny are described. We discuss possible functions of both adult and embryonic brain ventricles, as well as major brain defects that are associated with CSF and brain ventricular abnormalities. We conclude that vertebrates have taken advantage of their neural tube to form the essential brain ventricular system.

  6. Differentiating neural reward responsiveness in autism versus ADHD

    Directory of Open Access Journals (Sweden)

    Gregor Kohls

    2014-10-01

    Full Text Available Although attention deficit hyperactivity disorders (ADHD and autism spectrum disorders (ASD share certain neurocognitive characteristics, it has been hypothesized to differentiate the two disorders based on their brain's reward responsiveness to either social or monetary reward. Thus, the present fMRI study investigated neural activation in response to both reward types in age and IQ-matched boys with ADHD versus ASD relative to typically controls (TDC. A significant group by reward type interaction effect emerged in the ventral striatum with greater activation to monetary versus social reward only in TDC, whereas subjects with ADHD responded equally strong to both reward types, and subjects with ASD showed low striatal reactivity across both reward conditions. Moreover, disorder-specific neural abnormalities were revealed, including medial prefrontal hyperactivation in response to social reward in ADHD versus ventral striatal hypoactivation in response to monetary reward in ASD. Shared dysfunction was characterized by fronto-striato-parietal hypoactivation in both clinical groups when money was at stake. Interestingly, lower neural activation within parietal circuitry was associated with higher autistic traits across the entire study sample. In sum, the present findings concur with the assumption that both ASD and ADHD display distinct and shared neural dysfunction in response to reward.

  7. Reorganization of Functional Connectivity as a Correlate of Cognitive Recovery in Acquired Brain Injury

    Science.gov (United States)

    Castellanos, Nazareth P.; Paul, Nuria; Ordonez, Victoria E.; Demuynck, Olivier; Bajo, Ricardo; Campo, Pablo; Bilbao, Alvaro; Ortiz, Tomas; del-Pozo, Francisco; Maestu, Fernando

    2010-01-01

    Cognitive processes require a functional interaction between specialized multiple, local and remote brain regions. Although these interactions can be strongly altered by an acquired brain injury, brain plasticity allows network reorganization to be principally responsible for recovery. The present work evaluates the impact of brain injury on…

  8. Blood-Brain Barrier P-Glycoprotein Function in Neurodegenerative Disease

    NARCIS (Netherlands)

    Bartels, A. L.

    2011-01-01

    Protection of the brain is strengthened by active transport and ABC transporters. P-glycoprotein (P-gp) at the blood-brain barrier (BBB) functions as an active efflux pump by extruding a substrate from the brain, which is important for maintaining loco-regional homeostasis in the brain and protectio

  9. Brain structure and neural network of the reward/loss process in decision making%决策奖损加工的脑神经结构与环路

    Institute of Scientific and Technical Information of China (English)

    魏巍; 郭宗君

    2015-01-01

    目的 以国内外2005~2014年发表的针对与决策机制有关的关于奖赏、损失的神经结构及环路,及其与某些身心疾病关系的文献,综述决策奖损加工的脑神经结构及其意义,可以在一定程度上揭示行为决策的神经结构和网络机制,及其与某些身心疾病的关系.方法 2014年9月在PubMed、Science-Direct、中国知网和万方数据库等数据库,以“决策”、“奖赏”、“损失规避”等检索词,检索国内外有关决策奖损加工相关脑神经结构,及其与某些身心疾病的关系的研究.结果 检索文献110篇,纳入分析40篇.结果总结了大脑奖损结构及其关系在决策加工过程中的作用机制,以及两系统失衡所导致的身心疾病.结论 大部分文献认为奖赏趋近系统和损失规避系统的协调加工共同影响人们的行为决策,一旦上述系统平衡失调,则可出现行为决策障碍,产生一些身心疾病,但与决策行为模式相关的精确的神经机制尚须进一步研究.%Objective Based on the literatures published between 2005 and 2014,review the correlation between reward/loss of brain structure and neural network,and its relationship with physical and mental ailments,aim to reveal the neural structure and network of behavioral decision mechanism.Methods By retrieving literatures on PubMed,ScienceDirect,CNKI and Wanfang database in September 2014,we used "decision making","reward","loss aversion" and so on as the key words.Results Totally 40 papers were enrolled,the result reviewed the clinic meaning and the brain structure and neural network of the reward/loss process in decision making.Conclusion Most studies found the reward/loss decision making mechanism of the brain structure and the physical and mental ailments caused by the two systems imbalance,but related to the precise decision making neural mechanism has yet to be studied further.

  10. The function of neurocognitive networks. Comment on “Understanding brain networks and brain organization” by Pessoa

    Science.gov (United States)

    Bressler, Steven L.

    2014-09-01

    Pessoa [5] has performed a valuable service by reviewing the extant literature on brain networks and making a number of interesting proposals about their cognitive function. The term function is at the core of understanding the brain networks of cognition, or neurocognitive networks (NCNs) [1]. The great Russian neuropsychologist, Luria [4], defined brain function as the common task executed by a distributed brain network of complex dynamic structures united by the demands of cognition. Casting Luria in a modern light, we can say that function emerges from the interactions of brain regions in NCNs as they dynamically self-organize according to cognitive demands. Pessoa rightly details the mapping between brain function and structure, emphasizing both its pluripotency (one structure having multiple functions) and degeneracy (many structures having the same function). However, he fails to consider the potential importance of a one-to-one mapping between NCNs and function. If NCNs are uniquely composed of specific collections of brain areas, then each NCN has a unique function determined by that composition.

  11. RM-SORN: a reward-modulated self-organizing recurrent neural network.

    Science.gov (United States)

    Aswolinskiy, Witali; Pipa, Gordon

    2015-01-01

    Neural plasticity plays an important role in learning and memory. Reward-modulation of plasticity offers an explanation for the ability of the brain to adapt its neural activity to achieve a rewarded goal. Here, we define a neural network model that learns through the interaction of Intrinsic Plasticity (IP) and reward-modulated Spike-Timing-Dependent Plasticity (STDP). IP enables the network to explore possible output sequences and STDP, modulated by reward, reinforces the creation of the rewarded output sequences. The model is tested on tasks for prediction, recall, non-linear computation, pattern recognition, and sequence generation. It achieves performance comparable to networks trained with supervised learning, while using simple, biologically motivated plasticity rules, and rewarding strategies. The results confirm the importance of investigating the interaction of several plasticity rules in the context of reward-modulated learning and whether reward-modulated self-organization can explain the amazing capabilities of the brain.

  12. Reduced sensitivity to sooner reward during intertemporal decision-making following insula damage in humans

    Directory of Open Access Journals (Sweden)

    Manuela eSellitto

    2016-01-01

    Full Text Available During intertemporal choice, humans tend to prefer small-sooner rewards over larger-delayed rewards, reflecting temporal discounting (TD of delayed outcomes. Functional neuroimaging evidence has implicated the insular cortex in time-sensitive decisions, yet it is not clear whether activity in this brain region is crucial for, or merely associated with, TD behaviour. Here, patients with damage to the insula (Insular patients, control patients with lesions outside the insula, and healthy individuals chose between smaller-sooner and larger-later monetary rewards. Insular patients were less sensitive to sooner rewards than were the control groups, exhibiting reduced TD. A Voxel-based Lesion-Symptom Mapping (VLSM analysis confirmed a statistically significant association between insular damage and reduced TD. These results indicate that the insular cortex is crucial for intertemporal choice. We suggest that he insula may be necessary to anticipate the bodily/emotional effects of receiving rewards at different delays, influencing the computation of their incentive value. Devoid of such input, insular patients’ choices would be governed by a heuristic of quantity, allowing patients to wait for larger options.

  13. Art for reward's sake: visual art recruits the ventral striatum.

    Science.gov (United States)

    Lacey, Simon; Hagtvedt, Henrik; Patrick, Vanessa M; Anderson, Amy; Stilla, Randall; Deshpande, Gopikrishna; Hu, Xiaoping; Sato, João R; Reddy, Srinivas; Sathian, K

    2011-03-01

    A recent study showed that people evaluate products more positively when they are physically associated with art images than similar non-art images. Neuroimaging studies of visual art have investigated artistic style and esthetic preference but not brain responses attributable specifically to the artistic status of images. Here we tested the hypothesis that the artistic status of images engages reward circuitry, using event-related functional magnetic resonance imaging (fMRI) during viewing of art and non-art images matched for content. Subjects made animacy judgments in response to each image. Relative to non-art images, art images activated, on both subject- and item-wise analyses, reward-related regions: the ventral striatum, hypothalamus and orbitofrontal cortex. Neither response times nor ratings of familiarity or esthetic preference for art images correlated significantly with activity that was selective for art images, suggesting that these variables were not responsible for the art-selective activations. Investigation of effective connectivity, using time-varying, wavelet-based, correlation-purged Granger causality analyses, further showed that the ventral striatum was driven by visual cortical regions when viewing art images but not non-art images, and was not driven by regions that correlated with esthetic preference for either art or non-art images. These findings are consistent with our hypothesis, leading us to propose that the appeal of visual art involves activation of reward circuitry based on artistic status alone and independently of its hedonic value.

  14. Functional brain networks develop from a "local to distributed" organization.

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    Damien A Fair

    2009-05-01

    Full Text Available The mature human brain is organized into a collection of specialized functional networks that flexibly interact to support various cognitive functions. Studies of development often attempt to identify the organizing principles that guide the maturation of these functional networks. In this report, we combine resting state functional connectivity MRI (rs-fcMRI, graph analysis, community detection, and spring-embedding visualization techniques to analyze four separate networks defined in earlier studies. As we have previously reported, we find, across development, a trend toward 'segregation' (a general decrease in correlation strength between regions close in anatomical space and 'integration' (an increased correlation strength between selected regions distant in space. The generalization of these earlier trends across multiple networks suggests that this is a general developmental principle for changes in functional connectivity that would extend to large-scale graph theoretic analyses of large-scale brain networks. Communities in children are predominantly arranged by anatomical proximity, while communities in adults predominantly reflect functional relationships, as defined from adult fMRI studies. In sum, over development, the organization of multiple functional networks shifts from a local anatomical emphasis in children to a more "distributed" architecture in young adults. We argue that this "local to distributed" developmental characterization has important implications for understanding the development of neural systems underlying cognition. Further, graph metrics (e.g., clustering coefficients and average path lengths are similar in child and adult graphs, with both showing "small-world"-like properties, while community detection by modularity optimization reveals stable communities within the graphs that are clearly different between young children and young adults. These observations suggest that early school age children and adults

  15. Amphetamine Sensitization Alters Reward Processing in the Human Striatum and Amygdala

    Science.gov (United States)

    O’Daly, Owen G.; Joyce, Daniel; Tracy, Derek K.; Azim, Adnan; Stephan, Klaas E.; Murray, Robin M.; Shergill, Sukhwinder S.

    2014-01-01

    Dysregulation of mesolimbic dopamine transmission is implicated in a number of psychiatric illnesses characterised by disruption of reward processing and goal-directed behaviour, including schizophrenia, drug addiction and impulse control disorders associated with chronic use of dopamine agonists. Amphetamine sensitization (AS) has been proposed to model the development of this aberrant dopamine signalling and the subsequent dysregulation of incentive motivational processes. However, in humans the effects of AS on the dopamine-sensitive neural circuitry associated with reward processing remains unclear. Here we describe the effects of acute amphetamine administration, following a sensitising dosage regime, on blood oxygen level dependent (BOLD) signal in dopaminoceptive brain regions during a rewarded gambling task performed by healthy volunteers. Using a randomised, double-blind, parallel-groups design, we found clear evidence for sensitization to the subjective effects of the drug, while rewarded reaction times were unchanged. Repeated amphetamine exposure was associated with reduced dorsal striatal BOLD signal during decision making, but enhanced ventromedial caudate activity during reward anticipation. The amygdala BOLD response to reward outcomes was blunted following repeated amphetamine exposure. Positive correlations between subjective sensitization and changes in anticipation- and outcome-related BOLD signal were seen for the caudate nucleus and amygdala, respectively. These data show for the first time in humans that AS changes the functional impact of acute stimulant exposure on the processing of reward-related information within dopaminoceptive regions. Our findings accord with pathophysiological models which implicate aberrant dopaminergic modulation of striatal and amygdala activity in psychosis and drug-related compulsive disorders. PMID:24717936

  16. Amphetamine sensitization alters reward processing in the human striatum and amygdala.

    Directory of Open Access Journals (Sweden)

    Owen G O'Daly

    Full Text Available Dysregulation of mesolimbic dopamine transmission is implicated in a number of psychiatric illnesses characterised by disruption of reward processing and goal-directed behaviour, including schizophrenia, drug addiction and impulse control disorders associated with chronic use of dopamine agonists. Amphetamine sensitization (AS has been proposed to model the development of this aberrant dopamine signalling and the subsequent dysregulation of incentive motivational processes. However, in humans the effects of AS on the dopamine-sensitive neural circuitry associated with reward processing remains unclear. Here we describe the effects of acute amphetamine administration, following a sensitising dosage regime, on blood oxygen level dependent (BOLD signal in dopaminoceptive brain regions during a rewarded gambling task performed by healthy volunteers. Using a randomised, double-blind, parallel-groups design, we found clear evidence for sensitization to the subjective effects of the drug, while rewarded reaction times were unchanged. Repeated amphetamine exposure was associated with reduced dorsal striatal BOLD signal during decision making, but enhanced ventromedial caudate activity during reward anticipation. The amygdala BOLD response to reward outcomes was blunted following repeated amphetamine exposure. Positive correlations between subjective sensitization and changes in anticipation- and outcome-related BOLD signal were seen for the caudate nucleus and amygdala, respectively. These data show for the first time in humans that AS changes the functional impact of acute stimulant exposure on the processing of reward-related information within dopaminoceptive regions. Our findings accord with pathophysiological models which implicate aberrant dopaminergic modulation of striatal and amygdala activity in psychosis and drug-related compulsive disorders.

  17. Functional MRI of the brain: localisation of eloquent cortex in focal brain lesion therapy

    Energy Technology Data Exchange (ETDEWEB)

    Dymarkowski, S.; Sunaert, S.; Oostende, S. van; Hecke, P. van; Wilms, G.; Demaerel, P.; Marchal, G. [Department of Radiology, University Hospitals, Leuven (Belgium); Nuttin, B.; Plets, C. [Department of Neurosurgery, University Hospitals, Leuven (Belgium)

    1998-12-01

    The aim of this study was to assess the feasibility of functional MRI (fMRI) in a clinical environment on a large patient group, and to evaluate the pretherapeutic value of localisation of eloquent cortex. Forty patients with focal brain lesions of different origin were studied using fMRI. Functional information was obtained using motor, somatosensory, auditory and phonological stimuli depending on the localisation of the lesions. To obtain information about the spatial accuracy of fMRI, the results were compared with postoperative electrocortical stimulation. Two patients with secondary trigeminal neuralgia were scanned using a motor protocol and were implanted with an extradural plate electrode. Imaging was successful in 40 of 42 patients (including the 2 with trigeminal neuralgia). These patients were analysed for strength of activation, the relation of the lesion to activation sites and the presence of mass effect. The correlation between these data and surgical findings provided significant additional clinical information. Functional MRI can be accurately performed in patients with focal brain lesions using a dedicated approach. Functional MRI offers important clinical information as a contribution to a decrease in posttherapeutic morbidity. The accuracy of the technique can be confirmed by other modalities, including invasive cortical electrostimulation. (orig.) With 7 figs., 2 tabs., 25 refs.

  18. Using computational models to relate structural and functional brain connectivity.

    Science.gov (United States)

    Hlinka, Jaroslav; Coombes, Stephen

    2012-07-01

    Modern imaging methods allow a non-invasive assessment of both structural and functional brain connectivity. This has lead to the identification of disease-related alterations affecting functional connectivity. The mechanism of how such alterations in functional connectivity arise in a structured network of interacting neural populations is as yet poorly understood. Here we use a modeling approach to explore the way in which this can arise and to highlight the important role that local population dynamics can have in shaping emergent spatial functional connectivity patterns. The local dynamics for a neural population is taken to be of the Wilson-Cowan type, whilst the structural connectivity patterns used, describing long-range anatomical connections, cover both realistic scenarios (from the CoComac database) and idealized ones that allow for more detailed theoretical study. We have calculated graph-theoretic measures of functional network topology from numerical simulations of model networks. The effect of the form of local dynamics on the observed network state is quantified by examining the correlation between structural and functional connectivity. We document a profound and systematic dependence of the simulated functional connectivity patterns on the parameters controlling the dynamics. Importantly, we show that a weakly coupled oscillator theory explaining these correlations and their variation across parameter space can be developed. This theoretical development provides a novel way to characterize the mechanisms for the breakdown of functional connectivity in diseases through changes in local dynamics.

  19. Structure-function clustering in multiplex brain networks

    Science.gov (United States)

    Crofts, J. J.; Forrester, M.; O'Dea, R. D.

    2016-10-01

    A key question in neuroscience is to understand how a rich functional repertoire of brain activity arises within relatively static networks of structurally connected neural populations: elucidating the subtle interactions between evoked “functional connectivity” and the underlying “structural connectivity” has the potential to address this. These structural-functional networks (and neural networks more generally) are more naturally described using a multilayer or multiplex network approach, in favour of standard single-layer network analyses that are more typically applied to such systems. In this letter, we address such issues by exploring important structure-function relations in the Macaque cortical network by modelling it as a duplex network that comprises an anatomical layer, describing the known (macro-scale) network topology of the Macaque monkey, and a functional layer derived from simulated neural activity. We investigate and characterize correlations between structural and functional layers, as system parameters controlling simulated neural activity are varied, by employing recently described multiplex network measures. Moreover, we propose a novel measure of multiplex structure-function clustering which allows us to investigate the emergence of functional connections that are distinct from the underlying cortical structure, and to highlight the dependence of multiplex structure on the neural dynamical regime.

  20. Theoretical frameworks and mechanistic aspects of alcohol addiction: alcohol addiction as a reward deficit disorder.

    Science.gov (United States)

    Koob, George F

    2013-01-01

    Alcoholism can be defined by a compulsion to seek and take drug, loss of control in limiting intake, and the emergence of a negative emotional state when access to the drug is prevented. Alcoholism impacts multiple motivational mechanisms and can be conceptualized as a disorder that includes a progression from impulsivity (positive reinforcement) to compulsivity (negative reinforcement). The compulsive drug seeking associated with alcoholism can be derived from multiple neuroadaptations, but the thesis argued here is that a key component involves the construct of negative reinforcement. Negative reinforcement is defined as drug taking that alleviates a negative emotional state. The negative emotional state that drives such negative reinforcement is hypothesized to derive from dysregulation of specific neurochemical elements involved in reward and stress within the basal forebrain structures involving the ventral striatum and extended amygdala, respectively. Specific neurochemical elements in these structures include not only decreases in reward neurotransmission, such as decreased dopamine and γ-aminobutyric acid function in the ventral striatum, but also recruitment of brain stress systems, such as corticotropin-releasing factor (CRF), in the extended amygdala. Acute withdrawal from chronic alcohol, sufficient to produce dependence, increases reward thresholds, increases anxiety-like responses, decreases dopamine system function, and increases extracellular levels of CRF in the central nucleus of the amygdala. CRF receptor antagonists also block excessive drug intake produced by dependence. A brain stress response system is hypothesized to be activated by acute excessive drug intake, to be sensitized during repeated withdrawal, to persist into protracted abstinence, and to contribute to the compulsivity of alcoholism. Other components of brain stress systems in the extended amygdala that interact with CRF and that may contribute to the negative motivational state

  1. Mapping multiplex hubs in human functional brain networks

    Directory of Open Access Journals (Sweden)

    Alex Arenas

    2016-07-01

    Full Text Available Typical brain networks consist of many peripheral regions and a few highly centralones, i.e. hubs, playing key functional roles in cerebral inter-regional interactions. Studieshave shown that networks, obtained from the analysis of specific frequency components ofbrain activity, present peculiar architectures with unique profiles of region centrality. However,the identification of hubs in networks built from different frequency bands simultaneouslyis still a challenging problem, remaining largely unexplored. Here we identify eachfrequency component with one layer of a multiplex network and face this challenge by exploitingthe recent advances in the analysis of multiplex topologies. First, we show that eachfrequency band carries unique topological information, fundamental to accurately modelbrain functional networks. We then demonstrate that hubs in the multiplex network, in generaldifferent from those ones obtained after discarding or aggregating the measured signalsas usual, provide a more accurate map of brain’s most important functional regions, allowingto distinguish between healthy and schizophrenic populations better than conventionalnetwork approaches.

  2. Large-Scale Functional Brain Network Reorganization During Taoist Meditation.

    Science.gov (United States)

    Jao, Tun; Li, Chia-Wei; Vértes, Petra E; Wu, Changwei Wesley; Achard, Sophie; Hsieh, Chao-Hsien; Liou, Chien-Hui; Chen, Jyh-Horng; Bullmore, Edward T

    2016-02-01

    Meditation induces a distinct and reversible mental state that provides insights into brain correlates of consciousness. We explored brain network changes related to meditation by graph theoretical analysis of resting-state functional magnetic resonance imaging data. Eighteen Taoist meditators with varying levels of expertise were scanned using a within-subjects counterbalanced design during resting and meditation states. State-related differences in network topology were measured globally and at the level of individual nodes and edges. Although measures of global network topology, such as small-worldness, were unchanged, meditation was characterized by an extensive and expertise-dependent reorganization of the hubs (highly connected nodes) and edges (functional connections). Areas of sensory cortex, especially the bilateral primary visual and auditory cortices, and the bilateral temporopolar areas, which had the highest degree (or connectivity) during the resting state, showed the biggest decrease during meditation. Conversely, bilateral thalamus and components of the default mode network, mainly the bilateral precuneus and posterior cingulate cortex, had low degree in the resting state but increased degree during meditation. Additionally, these changes in nodal degree were accompanied by reorganization of anatomical orientation of the edges. During meditation, long-distance longitudinal (antero-posterior) edges increased proportionally, whereas orthogonal long-distance transverse (right-left) edges connecting bilaterally homologous cortices decreased. Our findings suggest that transient changes in consciousness associated with meditation introduce convergent changes in the topological and spatial properties of brain functional networks, and the anatomical pattern of integration might be as important as the global level of integration when considering the network basis for human consciousness.

  3. The heme oxygenase system and its functions in the brain.

    Science.gov (United States)

    Maines, M D

    2000-05-01

    The heme oxygenase (HO) system was identified in the early 1970s as a distinct microsomal enzyme system that catalyzes formation of bile pigments (Maines and Kappas, 1974). Up to the early 1990s the system was considered only as a "molecular wrecking ball" (Lane, 1998) for degradation of the heme molecule and production of toxic waste products, CO and bile pigments. For those years, the HO system remained relatively unknown to the research community. In a rather short span of the past 10 years following the discovery of high levels of a second form of the enzyme, HO-2, in the brain, suggesting that "heme oxygenase in the brain has functions aside from heme degradation" (Sun et al., 1990); concomitant with finding that another toxic gas, NO, is a signal molecule for generation of cGMP (Ignarro et al., 1982), the system was propelled into main stream research. This propulsion was fueled by the realization of the multiple and diverse functions of heme degradation products. Heme oxygenase has now found relevance in all kinds of human pathophysiology ranging from stroke, cancer, multiple sclerosis, and malaria to transplantation and immune response. As it turns out, its potential benefits are mesmerizing investigators in diverse fields (Lane, 1998). The most recent findings with HO-2 being a hemoprotein and potentially an intracellular "sink" for NO (McCoubrey et al., 1997a; Ding et al., 1999), together with the discovery of the third form of the enzyme, HO-3 (McCoubrey et al., 1997b), are likely to insure the widespread interest in the enzyme system in the coming years. The present review is intended to highlight molecular properties of HO isozymes and their likely functions in the brain. Extended reviews of the system are found in Maines (1992, 1997).

  4. Functional magnetic resonance imaging and the brain: A brief review

    Science.gov (United States)

    Chow, Maggie S M; Wu, Sharon L; Webb, Sarah E; Gluskin, Katie; Yew, D T

    2017-01-01

    Functional magnetic resonance imaging (fMRI) is employed in many behavior analysis studies, with blood oxygen level dependent- (BOLD-) contrast imaging being the main method used to generate images. The use of BOLD-contrast imaging in fMRI has been refined over the years, for example, the inclusion of a spin echo pulse and increased magnetic strength were shown to produce better recorded images. Taking careful precautions to control variables during measurement, comparisons between different specimen groups can be illustrated by fMRI imaging using both quantitative and qualitative methods. Differences have been observed in comparisons of active and resting, developing and aging, and defective and damaged brains in various studies. However, cognitive studies using fMRI still face a number of challenges in interpretation that can only be overcome by imaging large numbers of samples. Furthermore, fMRI studies of brain cancer, lesions and other brain pathologies of both humans and animals are still to be explored. PMID:28144401

  5. Bisphenol A Interaction With Brain Development and Functions

    Directory of Open Access Journals (Sweden)

    P. Negri-Cesi

    2015-06-01

    Full Text Available Brain development is an organized, but constantly adaptive, process in which genetic and epigenetic signals allow neurons to differentiate, to migrate, and to develop correct connections. Gender specific prenatal sex hormone milieu participates in the dimorphic development of many neuronal networks. Environmental cues may interfere with these developmental programs, producing adverse outcomes. Bisphenol A (BPA, an estrogenic/antiandrogenic endocrine disruptor widely diffused in the environment, produces adverse effects at levels below the acceptable daily intake. This review analyzes the recent literature on the consequences of perinatal exposure to BPA environmental doses on the development of a dimorphic brain. The BPA interference with the development and function of the neuroendocrine hypothalamus and of the nuclei controlling energy balance, and with the hippocampal memory processing is also discussed. The detrimental action of BPA appears complex, involving different hormonal and epigenetic pathways activated, often in a dimorphic way, within clearcut susceptibility windows. To date, discrepancies in experimental approaches and in related outcomes make unfeasible to translate the available information into clear dose–response models for human risk assessment. Evaluation of BPA brain levels in relation to the appearance of adverse effects in future basic studies will certainly give better definition of the warning threshold for human health.

  6. Brain oscillations and functional connectivity during overt language production

    Directory of Open Access Journals (Sweden)

    Arne eEwald

    2012-06-01

    Full Text Available In the present study we investigate the communication of different large scale brain sites during an overt language production task with state of the art methods for the estimation of EEG functional connectivity. Participants performed a semantic blocking task in which objects were named in semantically homogeneous blocks of trials consisting of members of a semantic category (e.g., all objects are tools or in heterogeneous blocks, consisting of unrelated objects. The classic pattern of slower naming times in the homogeneous relative to heterogeneous blocks is assumed to reflect the duration of lexical selection. For the collected data in the homogeneous and heterogeneous conditions the imaginary part of coherency (ImC was evaluated at different frequencies. The ImC is a measure for detecting the coupling of different brain sites acting on sensor level. Most importantly, a non-vanishing ImC cannot be explained by mixtures of independent sources and must therefore reflect true interactions. After performing a grand average over 24 subjects we analyzed the ImC at all pairs of 56 EEG channels across all frequencies. Contrasting the two experimental conditions we found differences in interaction between left temporal and frontal areas and frontal and occipital areas in the theta band at 7Hz, and also smaller differences in the delta and beta band. These areas are well-known to play a major role in lexical-semantic language processes. Our findings demonstrate the feasibility of investigating interactive brain activity during overt language production.

  7. Phasic and tonic fluctuations in brain, muscle and skin temperatures during motivated drinking behavior in rats: physiological correlates of motivation and reward

    OpenAIRE

    Smirnov, Michael S.; Kiyatkin, Eugene A.

    2009-01-01

    Since brain metabolism is accompanied by heat production, measurement of brain temperature offers a method for assessing global alterations in metabolic neural activity. This approach, high-resolution (5-s bin) temperature recording from the nucleus accumbens (NAcc), temporal muscle, and facial skin, was used to study motivated drinking behavior in rats. Experienced animals were presented with a cup containing 5-ml of Coca-Cola® (Coke) beverage that resulted, within certain latencies, in init...

  8. A Statistical Method to Distinguish Functional Brain Networks

    Science.gov (United States)

    Fujita, André; Vidal, Maciel C.; Takahashi, Daniel Y.

    2017-01-01

    One major problem in neuroscience is the comparison of functional brain networks of different populations, e.g., distinguishing the networks of controls and patients. Traditional algorithms are based on search for isomorphism between networks, assuming that they are deterministic. However, biological networks present randomness that cannot be well modeled by those algorithms. For instance, functional brain networks of distinct subjects of the same population can be different due to individual characteristics. Moreover, networks of subjects from different populations can be generated through the same stochastic process. Thus, a better hypothesis is that networks are generated by random processes. In this case, subjects from the same group are samples from the same random process, whereas subjects from different groups are generated by distinct processes. Using this idea, we developed a statistical test called ANOGVA to test whether two or more populations of graphs are generated by the same random graph model. Our simulations' results demonstrate that we can precisely control the rate of false positives and that the test is powerful to discriminate random graphs generated by different models and parameters. The method also showed to be robust for unbalanced data. As an example, we applied ANOGVA to an fMRI dataset composed of controls and patients diagnosed with autism or Asperger. ANOGVA identified the cerebellar functional sub-network as statistically different between controls and autism (p < 0.001). PMID:28261045

  9. Functional connectivity of the rodent brain using optical imaging

    Science.gov (United States)

    Guevara Codina, Edgar

    The aim of this thesis is to apply functional connectivity in a variety of animal models, using several optical imaging modalities. Even at rest, the brain shows high metabolic activity: the correlation in slow spontaneous fluctuations identifies remotely connected areas of the brain; hence the term "functional connectivity". Ongoing changes in spontaneous activity may provide insight into the neural processing that takes most of the brain metabolic activity, and so may provide a vast source of disease related changes. Brain hemodynamics may be modified during disease and affect resting-state activity. The thesis aims to better understand these changes in functional connectivity due to disease, using functional optical imaging. The optical imaging techniques explored in the first two contributions of this thesis are Optical Imaging of Intrinsic Signals and Laser Speckle Contrast Imaging, together they can estimate the metabolic rate of oxygen consumption, that closely parallels neural activity. They both have adequate spatial and temporal resolution and are well adapted to image the convexity of the mouse cortex. In the last article, a depth-sensitive modality called photoacoustic tomography was used in the newborn rat. Optical coherence tomography and laminar optical tomography were also part of the array of imaging techniques developed and applied in other collaborations. The first article of this work shows the changes in functional connectivity in an acute murine model of epileptiform activity. Homologous correlations are both increased and decreased with a small dependence on seizure duration. These changes suggest a potential decoupling between the hemodynamic parameters in resting-state networks, underlining the importance to investigate epileptic networks with several independent hemodynamic measures. The second study examines a novel murine model of arterial stiffness: the unilateral calcification of the right carotid. Seed-based connectivity analysis

  10. Crossed-Brain Representation of Verbal and Nonverbal Functions

    Directory of Open Access Journals (Sweden)

    Esmeralda Matute

    2015-01-01

    Full Text Available A 74-year-old, left-handed man presented with a rapidly evolving loss of strength in his right leg associated with difficulty in walking. MR images disclosed an extensive left hemisphere tumor. A neuropsychological examination revealed that language was broadly normal but that the patient presented with severe nonlinguistic abnormalities, including hemineglect (both somatic and spatial, constructional defects, and general spatial disturbances; symptoms were usually associated with right hemisphere pathologies. No ideomotor apraxia was found. The implications of crossed-brain representations of verbal and nonverbal functions are analyzed.

  11. The Apolipoprotein E Gene, Attention, and Brain Function

    OpenAIRE

    Parasuraman, Raja; Pamela M Greenwood; Sunderland, Trey

    2002-01-01

    The ɛ4 allele of the apolipoprotein E (ApoE) gene is associated with alterations in brain function and is a risk factor for Alzheimer’s disease (AD). Changes in components of visuospatial attention with ApoE-ɛ4, aging, and AD are described. Healthy middle-aged adults without dementia who have the ApoE-ɛ4 gene show deficits in spatial attention and working memory that are qualitatively similar to those seen in clinically diagnosed AD patients. The findings support an association between ApoE p...

  12. Changes in brain functional network connectivity after stroke

    Institute of Scientific and Technical Information of China (English)

    Wei Li; Yapeng Li; Wenzhen Zhu; Xi Chen

    2014-01-01

    Studies have shown that functional network connection models can be used to study brain net-work changes in patients with schizophrenia. In this study, we inferred that these models could also be used to explore functional network connectivity changes in stroke patients. We used independent component analysis to find the motor areas of stroke patients, which is a novel way to determine these areas. In this study, we collected functional magnetic resonance imaging datasets from healthy controls and right-handed stroke patients following their ifrst ever stroke. Using independent component analysis, six spatially independent components highly correlat-ed to the experimental paradigm were extracted. Then, the functional network connectivity of both patients and controls was established to observe the differences between them. The results showed that there were 11 connections in the model in the stroke patients, while there were only four connections in the healthy controls. Further analysis found that some damaged connections may be compensated for by new indirect connections or circuits produced after stroke. These connections may have a direct correlation with the degree of stroke rehabilitation. Our ifndings suggest that functional network connectivity in stroke patients is more complex than that in hea-lthy controls, and that there is a compensation loop in the functional network following stroke. This implies that functional network reorganization plays a very important role in the process of rehabilitation after stroke.

  13. From blood to brain: amoeboid microglial cell, a nascent macrophage and its functions in developing brain

    Institute of Scientific and Technical Information of China (English)

    Charanjit KAUR; S Thameem DHEEN; Eng-ang LING

    2007-01-01

    Amoeboid microglial cells (AMC) in the developing brain are active macrophages.The macrophagic nature of these cells has been demonstrated by many methods,such as the localization of various hydrolytic enzymes and the presence of comple-ment type 3 surface receptors in them. More importantly is the direct visualization of these cells engaged in the phagocytosis of degenerating cells at the ultrastruc-tural level. Further evidence of them being active macrophages is the avid inter-nalization of tracers administered by the intravenous or intraperitoneal routes in developing rats. The potential involvement of AMC in immune functions is sup-ported by the induced expression of major histocompatibility complex class Ⅰ and Ⅱ antigens on them when challenged by lipopolysaccharide or interferon-γ. Im-munosuppressive drugs, such as glucocorticoids and immune function-enhanc-ing drugs like melatonin, affect the expression of surface receptors and antigens and the release of cytokines by AMC. Recent studies in our laboratory have shown the expression of insulin-like growth factors, endothelins, 21,31-cyclic nucle-otide 31-phosphodiesterase, and N-methyl-D-asparate receptors. This along with the release of chemokines, such as stromal derived factor-la and monocyte chemoattractant protein-1, suggests multiple functional roles of AMC in early brain development.

  14. Influence of dopaminergically mediated reward on somatosensory decision-making.

    Directory of Open Access Journals (Sweden)

    Burkhard Pleger

    2009-07-01

    Full Text Available Reward-related dopaminergic influences on learning and overt behaviour are well established, but any influence on sensory decision-making is largely unknown. We used functional magnetic resonance imaging (fMRI while participants judged electric somatosensory stimuli on one hand or other, before being rewarded for correct performance at trial end via a visual signal, at one of four anticipated financial levels. Prior to the procedure, participants received either placebo (saline, a dopamine agonist (levodopa, or an antagonist (haloperidol.higher anticipated reward improved tactile decisions. Visually signalled reward reactivated primary somatosensory cortex for the judged hand, more strongly for higher reward. After receiving a higher reward on one trial, somatosensory activations and decisions were enhanced on the next trial. These behavioural and neural effects were all enhanced by levodopa and attenuated by haloperidol, indicating dopaminergic dependency. Dopaminergic reward-related influences extend even to early somatosensory cortex and sensory decision-making.

  15. Food and drug cues activate similar brain regions: a meta-analysis of functional MRI studies.

    Science.gov (United States)

    Tang, D W; Fellows, L K; Small, D M; Dagher, A

    2012-06-06

    In healthy individuals, food cues can trigger hunger and feeding behavior. Likewise, smoking cues can trigger craving and relapse in smokers. Brain imaging studies report that structures involved in appetitive behaviors and reward, notably the insula, striatum, amygdala and orbital frontal cortex, tend to be activated by both visual food and smoking cues. Here, by carrying out a meta-analysis of human neuro-imaging studies, we investigate the neural network activated by: 1) food versus neutral cues (14 studies, 142 foci) 2) smoking versus neutral cues (15 studies, 176 foci) 3) smoking versus neutral cues when correlated with craving scores (7 studies, 108 foci). PubMed was used to identify cue-reactivity imaging studies that compared brain response to visual food or smoking cues to neutral cues. Fourteen articles were identified for the food meta-analysis and fifteen articles were identified for the smoking meta-analysis. Six articles were identified for the smoking cue correlated with craving analysis. Meta-analyses were carried out using activation likelihood estimation. Food cues were associated with increased blood oxygen level dependent (BOLD) response in the left amygdala, bilateral insula, bilateral orbital frontal cortex, and striatum. Smoking cues were associated with increased BOLD signal in the same areas, with the exception of the insula. However, the smoking meta-analysis of brain maps correlating cue-reactivity with subjective craving did identify the insula, suggesting that insula activation is only found when craving levels are high. The brain areas identified here are involved in learning, memory and motivation, and their cue-induced activity is an index of the incentive salience of the cues. Using meta-analytic techniques to combine a series of studies, we found that food and smoking cues activate comparable brain networks. There is significant overlap in brain regions responding to conditioned cues associated with natural and drug rewards.

  16. Some Problems for Representations of Brain Organization Based on Activation in Functional Imaging

    Science.gov (United States)

    Sidtis, John J.

    2007-01-01

    Functional brain imaging has overshadowed traditional lesion studies in becoming the dominant approach to the study of brain-behavior relationships. The proponents of functional imaging studies frequently argue that this approach provides an advantage over lesion studies by observing normal brain activity in vivo without the disruptive effects of…

  17. Brain Structure and Executive Functions in Children with Cerebral Palsy: A Systematic Review

    Science.gov (United States)

    Weierink, Lonneke; Vermeulen, R. Jeroen; Boyd, Roslyn N.

    2013-01-01

    This systematic review aimed to establish the current knowledge about brain structure and executive function (EF) in children with cerebral palsy (CP). Five databases were searched (up till July 2012). Six articles met the inclusion criteria, all included structural brain imaging though no functional brain imaging. Study quality was assessed using…

  18. A Self-Study Tutorial using the Allen Brain Explorer and Brain Atlas to Teach Concepts of Mammalian Neuroanatomy and Brain Function.

    Science.gov (United States)

    Jenks, Bruce G

    2009-01-01

    The Allen Brain Atlas is a repository of neuroanatomical data concerning the mouse brain. The core of the database is a Nissl-stained reference atlas of the brain accompanied by in situ hybridization data for essentially the entire mouse genome. This database is freely available at the Allen Institute for Brain Science website, as is an innovative tool to explore the database, the Brain Explorer. This tool is downloaded and installed on your own computer. I have developed a self-study tutorial, "Explorations with the Allen Brain Explorer", which uses the Brain Explorer and the Brain Atlas to teach fundamentals of mammalian neuroanatomy and brain function. In this tutorial background information and step-by-step exercises on the use of the Brain Explorer are given using PowerPoint as a platform. To do the tutorial both the PowerPoint and the Brain Explorer are opened on the computer and the students switch from one program to the other as they go, in a step-wise fashion, through the various exercises. There are two main groups of exercises, titled "The Basics" and "Explorations", with both groups accessed from a PowerPoint "Start Menu" by clicking on dynamic links to the appropriate exercises. Most exercises have a number of dynamic links to PowerPoint slides where background information for the exercises is given or the neuroanatomical data collected from the Brain Atlas is discussed.

  19. Neuropsychology of reward learning and negative symptoms in schizophrenia

    OpenAIRE

    2014-01-01

    We used the Iowa Gambling Test (IGT) to examine the relationship of reward learning to both neuropsychological functioning and symptom formation in 65 individuals with schizophrenia. Results indicated that compared to controls, participants with schizophrenia showed significantly reduced reward learning, which in turn correlated with reduced intelligence, memory and executive function, and increased negative symptoms. The current findings suggested that a disease-related disturbance in reward...

  20. Neuropsychology of Reward Learning and Negative Symptoms in Schizophrenia

    OpenAIRE

    2014-01-01

    We used the Iowa Gambling Test (IGT) to examine the relationship of reward learning to both neuropsychological functioning and symptom formation in 65 individuals with schizophrenia. Results indicated that compared to controls, participants with schizophrenia showed significantly reduced reward learning, which in turn correlated with reduced intelligence, memory and executive function, and increased negative symptoms. The current findings suggested that a disease-related disturbance in reward...

  1. PET imaging reveals brain functional changes in internet gaming disorder

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Mei; Zhang, Ying; Du, Fenglei; Hou, Haifeng; Chao, Fangfang; Zhang, Hong [The Second Hospital of Zhejiang University School of Medicine, Department of Nuclear Medicine, Hangzhou, Zhejiang (China); Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou (China); Chen, Qiaozhen [The Second Hospital of Zhejiang University School of Medicine, Department of Nuclear Medicine, Hangzhou, Zhejiang (China); The Second Affiliated Hospital of Zhejiang University School of Medicine, Department of Psychiatry, Hangzhou (China)

    2014-07-15

    Internet gaming disorder is an increasing problem worldwide, resulting in critical academic, social, and occupational impairment. However, the neurobiological mechanism of internet gaming disorder remains unknown. The aim of this study is to assess brain dopamine D{sub 2} (D{sub 2})/Serotonin 2A (5-HT{sub 2A}) receptor function and glucose metabolism in the same subjects by positron emission tomography (PET) imaging approach, and investigate whether the correlation exists between D{sub 2} receptor and glucose metabolism. Twelve drug-naive adult males who met criteria for internet gaming disorder and 14 matched controls were studied with PET and {sup 11}C-N-methylspiperone ({sup 11}C-NMSP) to assess the availability of D{sub 2}/5-HT{sub 2A} receptors and with {sup 18}F-fluoro-D-glucose ({sup 18}F-FDG) to assess regional brain glucose metabolism, a marker of brain function. {sup 11}C-NMSP and {sup 18}F-FDG PET imaging data were acquired in the same individuals under both resting and internet gaming task states. In internet gaming disorder subjects, a significant decrease in glucose metabolism was observed in the prefrontal, temporal, and limbic systems. Dysregulation of D{sub 2} receptors was observed in the striatum, and was correlated to years of overuse. A low level of D{sub 2} receptors in the striatum was significantly associated with decreased glucose metabolism in the orbitofrontal cortex. For the first time, we report the evidence that D{sub 2} receptor level is significantly associated with glucose metabolism in the same individuals with internet gaming disorder, which indicates that D{sub 2}/5-HT{sub 2A} receptor-mediated dysregulation of the orbitofrontal cortex could underlie a mechanism for loss of control and compulsive behavior in internet gaming disorder subjects. (orig.)

  2. Abnormal regional brain function in Parkinson's disease: truth or fiction?

    Science.gov (United States)

    Ma, Yilong; Tang, Chengke; Moeller, James R; Eidelberg, David

    2009-04-01

    Normalization of regional measurements by the global mean is commonly employed to minimize inter-subject variability in functional imaging studies. This practice is based on the assumption that global values do not substantially differ between patient and control groups. In this issue of NeuroImage, Borghammer and colleagues challenge the validity of this assumption. They focus on Parkinson's disease (PD) and use computer simulations to show that lower global values can produce spurious increases in subcortical brain regions. The authors speculate that the increased signal observed in these areas in PD is artefactual and unrelated to localized changes in brain function. In this commentary, we summarize what is currently known of the relationship between regional and global metabolic activity in PD and experimental parkinsonism. We found that early stage PD patients exhibit global values that are virtually identical to those of age-matched healthy subjects. SPM analysis revealed increased normalized metabolic activity in a discrete set of biologically relevant subcortical brain regions. Because of their higher variability, the corresponding absolute regional measures did not differ across the two groups. Longitudinal imaging studies in this population showed that the subcortical elevations in normalized metabolism appeared earlier and progressed faster than did focal cortical or global metabolic reductions. The observed increases in subcortical activity, but not the global changes, correlated with independent clinical measures of disease progression. Multivariate analysis with SSM/PCA further confirmed that the abnormal spatial covariance structure of early PD is dominated by these subcortical increases as opposed to network-related reductions in cortical metabolic activity or global changes. Thus, increased subcortical activity in PD cannot be regarded as a simple artefact of global normalization. Moreover, stability of the normalized measurements, particularly at

  3. Functional specializations for music processing in the human newborn brain.

    Science.gov (United States)

    Perani, Daniela; Saccuman, Maria Cristina; Scifo, Paola; Spada, Danilo; Andreolli, Guido; Rovelli, Rosanna; Baldoli, Cristina; Koelsch, Stefan

    2010-03-09

    In adults, specific neural systems with right-hemispheric weighting are necessary to process pitch, melody, and harmony as well as structure and meaning emerging from musical sequences. It is not known to what extent the specialization of these systems results from long-term exposure to music or from neurobiological constraints. One way to address this question is to examine how these systems function at birth, when auditory experience is minimal. We used functional MRI to measure brain activity in 1- to 3-day-old newborns while they heard excerpts of Western tonal music and altered versions of the same excerpts. Altered versions either included changes of the tonal key or were permanently dissonant. Music evoked predominantly right-hemispheric activations in primary and higher order auditory cortex. During presentation of the altered excerpts, hemodynamic responses were significantly reduced in the right auditory cortex, and activations emerged in the left inferior frontal cortex and limbic structures. These results demonstrate that the infant brain shows a hemispheric specialization in processing music as early as the first postnatal hours. Results also indicate that the neural architecture underlying music processing in newborns is sensitive to changes in tonal key as well as to differences in consonance and dissonance.

  4. Dopamine and glucose, obesity, and reward deficiency syndrome.

    Science.gov (United States)

    Blum, Kenneth; Thanos, Panayotis K; Gold, Mark S

    2014-01-01

    Obesity as a result of overeating as well as a number of well described eating disorders has been accurately considered to be a world-wide epidemic. Recently a number of theories backed by a plethora of scientifically sound neurochemical and genetic studies provide strong evidence that food addiction is similar to psychoactive drug addiction. Our laboratory has published on the concept known as Reward Deficiency Syndrome (RDS) which is a genetic and epigenetic phenomena leading to impairment of the brain reward circuitry resulting in a hypo-dopaminergic function. RDS involves the interactions of powerful neurotransmitters and results in abnormal craving behavior. A number of important facts which could help translate to potential therapeutic targets espoused in this focused review include: (1) consumption of alcohol in large quantities or carbohydrates binging stimulates the brain's production of and utilization of dopamine; (2) in the meso-limbic system the enkephalinergic neurons are in close proximity, to glucose receptors; (3) highly concentrated glucose activates the calcium channel to stimulate dopamine release from P12 cells; (4) a significant correlation between blood glucose and cerebrospinal fluid concentrations of homovanillic acid the dopamine metabolite; (5) 2-deoxyglucose (2DG), the glucose analog, in pharmacological doses is associated with enhanced dopamine turnover and causes acute glucoprivation. Evidence from animal studies and fMRI in humans support the hypothesis that multiple, but similar brain circuits are disrupted in obesity and drug dependence and for the most part, implicate the involvement of DA-modulated reward circuits in pathologic eating behaviors. Based on a consensus of neuroscience research treatment of both glucose and drug like cocaine, opiates should incorporate dopamine agonist therapy in contrast to current theories and practices that utilizes dopamine antagonistic therapy. Considering that up until now clinical utilization

  5. Alteration and reorganization of functional networks: a new perspective in brain injury study

    Directory of Open Access Journals (Sweden)

    Nazareth P. Castellanos

    2011-09-01

    Full Text Available Plasticity is the mechanism underlying brain’s potential capability to compensate injury. Recently several studies have shown that functional connections among brain areas are severely altered by brain injury and plasticity leading to a reorganization of the networks. This new approach studies the impact of brain injury by means of alteration of functional interactions. The concept of functional connectivity refers to the statistical interdependencies between physiological time series simultaneously recorded in various brain areas and it could be an essential tool for brain function studies, being its deviation from healthy reference an indicator for damage. In this article, we review studies investigating functional connectivity changes after brain injury and subsequent recovery, providing an accessible introduction to common mathematical methods to infer functional connectivity, exploring their capabilities, future perspectives and clinical uses in brain injury studies.

  6. Associations among smoking, anhedonia, and reward learning in depression.

    Science.gov (United States)

    Liverant, Gabrielle I; Sloan, Denise M; Pizzagalli, Diego A; Harte, Christopher B; Kamholz, Barbara W; Rosebrock, Laina E; Cohen, Andrew L; Fava, Maurizio; Kaplan, Gary B

    2014-09-01

    Depression and cigarette smoking co-occur at high rates. However, the etiological mechanisms that contribute to this relationship remain unclear. Anhedonia and associated impairments in reward learning are key features of depression, which also have been linked to the onset and maintenance of cigarette smoking. However, few studies have investigated differences in anhedonia and reward learning among depressed smokers and depressed nonsmokers. The goal of this study was to examine putative differences in anhedonia and reward learning in depressed smokers (n=36) and depressed nonsmokers (n=44). To this end, participants completed self-report measures of anhedonia and behavioral activation (BAS reward responsiveness scores) and as well as a probabilistic reward task rooted in signal detection theory, which measures reward learning (Pizzagalli, Jahn, & O'Shea, 2005). When considering self-report measures, depressed smokers reported higher trait anhedonia and reduced BAS reward responsiveness scores compared to depressed nonsmokers. In contrast to self-report measures, nicotine-satiated depressed smokers demonstrated greater acquisition of reward-based learning compared to depressed nonsmokers as indexed by the probabilistic reward task. Findings may point to a potential mechanism underlying the frequent co-occurrence of smoking and depression. These results hig