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Inhibitory Control (inhibitory + control)
Selected AbstractsAnger and Approach Motivation in Infancy: Relations to Early Childhood Inhibitory Control and Behavior ProblemsINFANCY, Issue 3 2010Jie He The relations among infant anger reactivity, approach behavior, and frontal electroencephalogram (EEG) asymmetry, and their relations to inhibitory control and behavior problems in early childhood were examined within the context of a longitudinal study of temperament. Two hundred nine infants' anger expressions to arm restraint were observed at 4 months of age. Infants' approach behaviors during play with an unpredictable toy and baseline frontal EEG asymmetry were assessed at 9 months of age. Inhibitory control during a Go/No-Go task and parent report of behavior problems were evaluated at 4 years of age. High anger-prone infants with left, but not right, frontal EEG asymmetry showed significantly more approach behaviors and less inhibitory control relative to less anger-prone infants. Although a link between anger proneness in infancy and behavior problems in early childhood was not found, a combination of low approach behaviors and poor inhibitory control was predictive of internalizing behaviors. [source] Event-Related fMRI of Inhibitory Control in the Predominantly Inattentive and Combined Subtypes of ADHDJOURNAL OF NEUROIMAGING, Issue 3 2009Mary V. Solanto PhD ABSTRACT BACKGROUND AND PURPOSE To examine the neurophysiological basis for the pronounced differences in hyperactivity and impulsiveness that distinguish the predominantly inattentive type of attention-deficit/hyperactivity disorder (ADHD-PI) from the combined type of the disorder (ADHD-C). METHODS Event-related brain responses to a go/no-go test of inhibitory control were measured with functional magnetic resonance imaging (fMRI) in 11 children with ADHD-C and 9 children with ADHD-PI, aged 7 to 13 years, who were matched for age, sex, and intelligence. RESULTS There were no significant group differences in task performance. Children with ADHD-C and ADHD-PI activated overlapping regions of right inferior frontal gyrus, right superior temporal lobe, and left inferior parietal lobe during inhibitory control. However, the magnitude of the activation in the temporal and parietal regions, as well as in the bilateral middle frontal gyrus, was greater in children with ADHD-PI than those with ADHD-C. Conversely, children with ADHD-C activated bilateral medial occipital lobe to a greater extent than children with ADHD-PI. CONCLUSIONS The results provide preliminary evidence that phenotypic differences between the ADHD-C and ADHD-PI subtypes are associated with differential activation of regions that have previously been implicated in the pathophysiology of ADHD and are thought to mediate executive and attentional processes. [source] Acute Alcohol Effects on Inhibitory Control and Implicit Cognition: Implications for Loss of Control Over DrinkingALCOHOLISM, Issue 8 2010Matt Field Alcohol impairs inhibitory control, and it alters implicit alcohol cognitions including attentional bias and implicit associations. These effects are seen after doses of alcohol which do not lead to global impairments in cognitive performance. We review studies which demonstrate that the effects of alcohol on inhibitory control are associated with the ability of alcohol to prime alcohol-seeking behavior. We also hypothesize that alcohol-induced changes in implicit alcohol cognitions may partially mediate alcohol-induced priming of the motivation to drink. Based on contemporary theoretical models and conceptualizations of executive function, impulsivity, and the motivational salience of alcohol-related cues, we speculate on other aspects of cognition that may underlie alcohol's effects on alcohol seeking. Inconsistencies in existing research and priorities for future research are highlighted, including dose effects and the potential interactions between chronic heavy drinking and the acute effects of alcohol on these cognitive processes. [source] Prenatal Alcohol Exposure Affects Frontal,Striatal BOLD Response During Inhibitory ControlALCOHOLISM, Issue 8 2007Susanna L. Fryer Background: Prenatal alcohol exposure can lead to widespread cognitive impairment and behavioral dysregulation, including deficits in attention and response inhibition. This study characterized the neural substrates underlying the disinhibited behavioral profile of individuals with fetal alcohol spectrum disorders (FASD). Methods: Children and adolescents (ages 8,18) with (n=13) and without (n=9) histories of heavy prenatal alcohol exposure underwent functional magnetic resonance imaging while performing a response inhibition (go/no-go) task. Results: Despite similar task performance (mean response latency, performance accuracy, and signal detection), blood oxygen level-dependent (BOLD) response patterns differed by group. Region-of-interest analyses revealed that during portions of the behavioral task that required response inhibition, alcohol-exposed participants showed greater BOLD response across prefrontal cortical regions (including the left medial and right middle frontal gyri), while they showed less right caudate nucleus activation, compared with control participants. Conclusions: These data provide an account of response inhibition-related brain functioning in youth with FASD. Furthermore, results suggest that the frontal,striatal circuitry thought to mediate inhibitory control is sensitive to alcohol teratogenesis. [source] Early developmental precursors of impulsive and inattentive behavior: from infancy to middle childhoodTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 4 2002Sheryl L. Olson Background: We examined infancy and toddler-age precursors of impulsivity and inattention in school-age children. Children (50 boys, 39 girls) had been participants since infancy in the Bloomington Longitudinal Study. Method: Individual differences in children's self-regulatory competence were assessed at 8 years of age, using laboratory tests and observations of three central constructs: Inhibitory Control, Behavioral Control, and Attentional Disengagement. Results: We found that measures of caregiver,child interaction, child temperament, and child cognitive competence during the toddler period significantly predicted variations in children's later impulsive functioning. However, the strength of these relationships, and the type and combination of significant risk factors, were differentially patterned in relation to specific subtypes of later child impulsivity. Conclusions: These data provide further evidence for the multidimensional nature of child impulsivity, and they highlight the importance of examining toddler-age precursors of children's later self-regulatory competence. [source] Anger and Approach Motivation in Infancy: Relations to Early Childhood Inhibitory Control and Behavior ProblemsINFANCY, Issue 3 2010Jie He The relations among infant anger reactivity, approach behavior, and frontal electroencephalogram (EEG) asymmetry, and their relations to inhibitory control and behavior problems in early childhood were examined within the context of a longitudinal study of temperament. Two hundred nine infants' anger expressions to arm restraint were observed at 4 months of age. Infants' approach behaviors during play with an unpredictable toy and baseline frontal EEG asymmetry were assessed at 9 months of age. Inhibitory control during a Go/No-Go task and parent report of behavior problems were evaluated at 4 years of age. High anger-prone infants with left, but not right, frontal EEG asymmetry showed significantly more approach behaviors and less inhibitory control relative to less anger-prone infants. Although a link between anger proneness in infancy and behavior problems in early childhood was not found, a combination of low approach behaviors and poor inhibitory control was predictive of internalizing behaviors. [source] Inhibitory control and spatial working memory in Parkinson's diseaseMOVEMENT DISORDERS, Issue 10 2007Caroline Gurvich DPsych (Clin Neuro) Abstract Patients with Parkinson's disease (PD) have difficulty performing tasks relying on inhibitory control and working memory, functions of the prefrontal cortex. Eye movement paradigms can be used to investigate basic sensorimotor functions and higher order cognitive aspects of motor control. This study investigated inhibitory control and spatial working memory in the saccadic system of 13 individuals with mild-moderate PD and 13 age-matched controls. Tasks explored suppression of reflexive saccades during qualitatively different tasks, generation of express and anticipatory saccades, and the ability to respond to occasional, unpredictable ("oddball") targets that occurred during a sequence of well-learned, reciprocating saccades between horizontal targets. Spatial working memory was assessed using single and two-step (involving a visually guided saccade during the delay period) memory-guided tasks. Results for the PD group indicated an increased percentage of response selection errors during an oddball task, reduced suppression of inappropriate reflexive saccades during memory-guided tasks (but not during fixation or saccade-engagement tasks), and an increased percentage of express and anticipatory saccades. Spatial working memory was preserved in the PD group during single and two-step memory-guided tasks. These findings are consistent with dysfunction within fronto-striatal and prefrontal-collicular pathways influencing suppression and selection of eye movements. © 2007 Movement Disorder Society [source] Physiological and neuropsychological correlates of approach/withdrawal tendencies in preschool: Further examination of the behavioral inhibition system/behavioral activation system scales for young childrenDEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2004Clancy Blair Abstract This study examined a parent-report version of the Behavioral Inhibition System/Behavioral Activation System (BIS/BAS) scales, a measure of approach,withdrawal motivation, in 170 children between the ages of 3 to 5 years attending Head Start programs. Physiological measures included assessments of baseline salivary cortisol and change in cortisol in response to the assessment session, and resting and suppression estimates of cardiac vagal tone. Cognitive self-regulation was assessed with a peg-tapping measure of inhibitory control and an item-selection measure of cognitive set-shifting ability. Results indicated that higher level of parent-reported withdrawal motivation was associated with cortisol increase and that parent-reported approach motivation tended to be associated with cortisol decrease across the assessment session. Higher level of parent-reported withdrawal also was positively related to cognitive self-regulation while parent-reported approach was negatively related to cognitive self-regulation. Person-oriented analysis indicated that children characterized by both high level of approach and high level of withdrawal tended to exhibit lower resting vagal tone, higher initial cortisol, and minimal cortisol and vagal change. Overall, findings suggest that the parent-report version of the BIS/BAS scales works well as an indicator of children's reactivity to appetitive and aversive motivational stimuli. Directions for future research and implications of findings for the longitudinal study of temperament and personality are discussed. © 2004 Wiley Periodicals, Inc. Dev Psychobiol 45: 113-124, 2004. [source] The effect of divided attention on inhibiting the gravity errorDEVELOPMENTAL SCIENCE, Issue 3 2006Bruce M. Hood Children who could overcome the gravity error on Hood's (1995) tubes task were tested in a condition where they had to monitor two falling balls. This condition significantly impaired search performance with the majority of mistakes being gravity errors. In a second experiment, the effect of monitoring two balls was compared in the tubes task and a spatial transposition task not involving gravity. Again, monitoring two objects produced impaired search performance in the gravity task but not in the spatial transposition task. These findings support the view that divided attention disrupts the ability to exercise inhibitory control over the gravity error and that the performance drop on this task is not due to the additional task demands incurred by divided attention. [source] The role of perseveration in children's symbolic understanding and skillDEVELOPMENTAL SCIENCE, Issue 3 2003Tanya Sharon In the first few years of life, children become increasingly sensitive to the significance of a variety of symbolic artifacts. An extensive body of research has explored very young children's ability to use symbol-based information as a guide to current reality. In one common task, for example, children watch as a miniature toy is hidden in a scale model, and are then asked to retrieve a larger version of the toy from the corresponding place in the room itself. Two-and-a-half-year-old children perform very poorly in most versions of this task. Their most common error is to perseverate; that is, they search again at the location where the toy was last hidden. Two studies examined the degree to which 21/2 -year-olds' high rate of perseveration and poor performance stem from problems with inhibitory control. Results showed that problems with inhibitory control contribute very little to 21/2 -year-old children's difficulty with the task. Instead, the results confirm young children's great difficulty appreciating and exploiting symbol,referent relations. [source] Acute alcohol impairs conditioning of a behavioural reward-seeking response and inhibitory control processes,implications for addictive disordersADDICTION, Issue 12 2009Sabine Loeber ABSTRACT Aims To investigate whether acute alcohol would affect performance of a conditioned behavioural response to obtain a reward outcome and impair performance in a task measuring inhibitory control to provide new knowledge of how the acute effects of alcohol might contribute to the transition from alcohol use to dependence. Design A randomized controlled between-subjects design was employed. Settings The laboratory of experimental psychology at the University of Sussex. Participants Thirty-two light to moderate social drinkers recruited from the undergraduate and postgraduate population. Measurements After the administration of alcohol (0.8 g/kg) or placebo participants underwent an instrumental reward-seeking procedure, with abstract stimuli serving as S+ (always predicting a win of 10 pence) and S, (always predicting a loss of 10 pence). In addition, a Stop Signal task was administered before and after the administration of alcohol. Findings Participants of the alcohol group performed the behavioural response to obtain the reward outcome more often than placebo subjects in trials associated with loss of money. This finding was observed, although alcohol was not affecting explicit knowledge of stimulus,response outcome contingencies and acquisition of conditioned attentional and emotional responses. In addition, alcohol increased Stop Signal reaction time indicating disinhibiting effects of alcohol, and this was associated positively with response probability to the S,. Conclusions These results demonstrate that alcohol is affecting inhibitory control of behavioural responses to external signals even when associated with punishment, contributing in this way to the transition from alcohol use to dependence. [source] Patterns of change in withdrawal symptoms, desire to smoke, reward motivation and response inhibition across 3 months of smoking abstinenceADDICTION, Issue 5 2009Lynne Dawkins ABSTRACT Aims We have demonstrated previously that acute smoking abstinence is associated with lowered reward motivation and impaired response inhibition. This prospective study explores whether these impairments, along with withdrawal-related symptoms, recover over 3 months of sustained abstinence. Design Participants completed a 12-hour abstinent baseline assessment and were then allocated randomly to quit unaided or continue smoking. All were re-tested after 7 days, 1 month and 3 months. Successful quitters' scores were compared with those of continuing smokers, who were tested after ad libitum smoking. Setting Goldsmiths, University of London. Participants A total of 33 smokers who maintained abstinence to 3 months, and 31 continuing smokers. Measurements Indices demonstrated previously in this cohort of smokers to be sensitive to the effect of nicotine versus acute abstinence: reward motivation [Snaith,Hamilton pleasure scale (SHAPS), Card Arranging Reward Responsivity Objective Test (CARROT), Stroop], tasks of response inhibition [anti-saccade task; Continuous Performance Task (CPT)], clinical indices of mood [Hospital Anxiety and Depression Scale (HADS)], withdrawal symptoms [Mood and Physical Symptoms Scale (MPSS)] and desire to smoke. Findings SHAPS anhedonia and reward responsivity (CARROT) showed significant improvement and plateaued after a month of abstinence, not differing from the scores of continuing smokers tested in a satiated state. Mood, other withdrawal symptoms and desire to smoke all declined from acute abstinence to 1 month of cessation and were equivalent to, or lower than, the levels reported by continuing, satiated smokers. Neither group showed a change in CPT errors over time while continuing smokers, but not abstainers, showed improved accuracy on the anti-saccade task at 3 months. Conclusion Appetitive processes and related affective states appear to improve in smokers who remain nicotine-free for 3 months, whereas response inhibition does not. Although in need of replication, the results suggest tentatively that poor inhibitory control may constitute a long-term risk factor for relapse and could be a target for intervention. [source] Corticolimbic dysregulation and chronic methamphetamine abuseADDICTION, Issue 2007Kate Baicy ABSTRACT Aims This review aims to present and interpret evidence that methamphetamine dependence is associated with disorder of brain function that is required for top-down control of behavior. Approach Presented here are findings from brain imaging studies of human research participants with histories of chronic methamphetamine abuse in the context of functional consequences and implications for treatment of their dependence on methamphetamine. Findings Brain imaging studies have revealed differences in the brains of research participants who have used methamphetamine chronically and then abstained from taking the drug, compared with healthy control subjects. These abnormalities are prominent in cortical and limbic systems, and include deficits in markers of dopaminergic and serotonergic neurotransmitter systems, differences in glucose metabolism and deficits in gray matter. These abnormalities accompany cognitive deficits, including evidence of impaired inhibitory control. Conclusion Cortical deficits in abstinent methamphetamine abusers can affect a wide range of functions that can be important for success in maintaining drug abstinence. These include but are not limited to modulation of responses to environmental stimuli as well as internal triggers that can lead to craving and relapse. Potential therapies may combine behavioral approaches with medications that can improve cognitive control. [source] Propagation Dynamics of Epileptiform Activity Acutely Induced by Bicuculline in the Hippocampal,Parahippocampal Region of the Isolated Guinea Pig BrainEPILEPSIA, Issue 12 2005Laura Uva Summary:,Purpose: Aim of the study is to investigate the involvement of parahippocampal subregions in the generation and in the propagation of focal epileptiform discharges in an acute model of seizure generation in the temporal lobe induced by arterial application of bicuculline in the in vitro isolated guinea pig brain preparation. Methods: Electrophysiological recordings were simultaneously performed with single electrodes and multichannel silicon probes in the entorhinal, perirhinal, and piriform cortices and in the area CA1 of the hippocampus of the in vitro isolated guinea pig brain. Interictal and ictal epileptiform discharges restricted to the temporal region were induced by a brief (3,5 min) arterial perfusion of the GABAA receptor antagonist, bicuculline methiodide (50 ,M). Current source density analysis of laminar field profiles performed with the silicon probes was carried out at different sites to establish network interactions responsible for the generation of epileptiform potentials. Nonlinear regression analysis was conducted on extracellular recordings during ictal onset in order to quantify the degree of interaction between fast activities generated at different sites, as well as time delays. Results: Experiments were performed in 31 isolated guinea pig brains. Bicuculline-induced interictal and ictal epileptiform activities that showed variability of spatial propagation and time course in the olfactory,temporal region. The most commonly observed pattern (n = 23) was characterized by the initial appearance of interictal spikes (ISs) in the piriform cortex (PC), which propagated to the lateral entorhinal region. Independent and asynchronous preictal spikes originated in the entorhinal cortex (EC)/hippocampus and progressed into ictal fast discharges (around 25 Hz) restricted to the entorhinal/hippocampal region. The local generation of fast activity was verified and confirmed both by CSD and phase shift analysis performed on laminar profiles. Fast activity was followed by synchronous afterdischarges that propagated to the perirhinal cortex (PRC) (but not to the PC). Within 1,9 min, the ictal discharge ceased and a postictal period of depression occurred, after which periodic ISs in the PC resumed. Unlike preictal ISs, postictal ISs propagated to the PRC. Conclusions: Several studies proposed that reciprocal connections between the entorhinal and the PRC are under a very efficient inhibitory control (1). We report that ISs determined by acute bicuculline treatment in the isolated guinea pig brain progress from the PC to the hippocampus/EC just before ictal onset. Ictal discharges are characterized by a peculiar pattern of fast activity that originates from the entorhinal/hippocampal region and only secondarily propagates to the PRC. Postictal propagation of ISs to the PRC occured exclusively when an ictal discharge was generated in the hippocampal/entorhinal region. The results suggest that reiteration of ictal events may promote changes in propagation pattern of epileptiform discharges that could act as trigger elements in the development of temporal lobe epilepsy. [source] Cortical control of thermoregulatory sympathetic activationEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2010M. Fechir Abstract Thermoregulation enables adaptation to different ambient temperatures. A complex network of central autonomic centres may be involved. In contrast to the brainstem, the role of the cortex has not been clearly evaluated. This study was therefore designed to address cerebral function during a whole thermoregulatory cycle (cold, neutral and warm stimulation) using 18-fluordeoxyglucose-PET (FDG-PET). Sympathetic activation parameters were co-registered. Ten healthy male volunteers were examined three times on three different days in a water-perfused whole-body suit. After a baseline period (32°C), temperature was either decreased to 7°C (cold), increased to 50°C (warm) or kept constant (32°C, neutral), thereafter the PET examination was performed. Cerebral glucose metabolism was increased in infrapontine brainstem and cerebellar hemispheres during cooling and warming, each compared with neutral temperature. Simultaneously, FDG uptake decreased in the bilateral anterior/mid-cingulate cortex during warming, and in the right insula during cooling and warming. Conjunction analyses revealed that right insular deactivation and brainstem activation appeared both during cold and warm stimulation. Metabolic connectivity analyses revealed positive correlations between the cortical activations, and negative correlations between these cortical areas and brainstem/cerebellar regions. Heart rate changes negatively correlated with glucose metabolism in the anterior cingulate cortex and in the middle frontal gyrus/dorsolateral prefrontal cortex, and changes of sweating with glucose metabolism in the posterior cingulate cortex. In summary, these results suggest that the cerebral cortex exerts an inhibitory control on autonomic centres located in the brainstem or cerebellum. These findings may represent reasonable explanations for sympathetic hyperactivity, which occurs, for example, after hemispheric stroke. [source] Contrasting effects of selective lesions of nucleus accumbens core or shell on inhibitory control and amphetamine-induced impulsive behaviourEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2008E. R. Murphy Abstract The core and shell subregions of the nucleus accumbens receive differential projections from areas of the medial prefrontal cortex that have dissociable effects on impulsive and perseverative responding. The contributions of these subregions to simple instrumental behaviour, inhibitory control and behavioural flexibility were investigated using a ,forced choice' task, various parameter manipulations and an omission schedule version of the task. Post-training, selective core lesions were achieved with microinjections of quinolinic acid and shell lesions with ibotenic acid. After a series of behavioural task manipulations, rats were re-stabilized on the standard version of the task and challenged with increasing doses of d - amphetamine (vehicle, 0.5 or 1.0 mg/kg i.p. 30 min prior to test). Neither core- nor shell-lesioned rats exhibited persistent deficits in simple instrumental behaviour or challenges to behavioural flexibility or inhibitory control. Significant differences between lesion groups were unmasked by d- amphetamine challenge in the standard version of the forced task. Core lesions potentiated and shell lesions attenuated the dose-dependent effect of d- amphetamine on increasing anticipatory responses seen in sham rats. These data imply that the accumbens core and shell subregions do not play major roles in highly-trained task performance or in challenges to behavioural control, but may have opposed effects following d- amphetamine treatment. Specifically, they suggest the shell subregion to be necessary for dopaminergic activation driving amphetamine-induced impulsive behaviour and the core subregion for the normal control of this behaviour via conditioned influences. [source] Serotonin transporter deficiency in rats improves inhibitory control but not behavioural flexibilityEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2007Judith R. Homberg Abstract Impulsivity and aggression have been suggested to inversely correlate with central serotonin (5-HT) levels in a trait-like manner. However, this relationship is far from straightforward. In the present study we addressed the effect of lifelong reduced or absent serotonin transporter (SERT) function, which is associated with constitutively increased extracellular 5-HT levels, on impulsivity and aggression. We used unique SERT knockout rats in a resident,intruder test, five-choice serial reaction time task and serial reversal learning task to assay aggression, inhibitory control and behavioural flexibility, respectively. Homozygous SERT knockout rats (SERT,,/,) displayed reduced aggression and improved inhibitory control, but unchanged behavioural flexibility. The behavioural phenotype of heterozygous SERT knockout rats (SERT,+/,) was not different from that of wild-type controls in any of the behavioural paradigms. We determined monoamine (metabolite) tissue levels in the medial prefrontal cortex, orbitofrontal cortex, lateral hypothalamus, raphe nuclei and cerebrospinal fluid, and found that the 5-HT levels, but not other monoamine tissue levels, were reduced in SERT,,/, rats. In addition, the 5-hydroxyindoleacetic acid (5-HIAA)/5-HT ratio in cerebrospinal fluid was increased in these rats. In conclusion, our data show that the absence of the SERT affects aggression and inhibitory control, but not behavioural flexibility, characteristics that may reflect the trait-like consequences of constitutive changes in central 5-HT levels. [source] Selective prefrontal serotonin depletion impairs acquisition of a detour-reaching taskEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2006S.C. Walker Abstract We have recently shown that serotonin in the primate orbitofrontal cortex (OFC) contributes to the flexible control of behaviour. 5,7-dihydroxytryptamine-induced 5-HT depletions of OFC impair performance on a serial reversal discrimination task [Clarke et al. (2004)Science, 304, 878,880]. The deficit is characterized by perseverative responding to the previously rewarded stimulus, a deficit similar to that seen following lesions of the intrinsic neurones of the OFC [Dias et al. (1996)Nature, 380, 69,72]. The effect is neurochemically selective as dopaminergic lesions of the OFC, induced by 6-hydroxydopamine, have no effect [Clarke et al. (2006)Cerebral Cortex]. In order to test for the generality of the effect of serotonin on orbitofrontal processing and, in particular, its effects on flexible behaviour, the present study investigated the effects of serotonin depletions of OFC on performance of another task dependent upon an intact OFC, the detour-reaching task [Wallis et al. (2001)European Journal of Neuroscience, 13, 1797,1808]. Successful performance of this task requires inhibition of the animal's prepotent response tendency to reach directly along its line of sight to the reward. Compared with sham-operated controls, we found that lesioned monkeys made significantly more barrier reaches directly along their line of sight to the visible reward during task acquisition. This finding provides further support for the role of prefrontal serotonin in inhibitory control processes specifically in tasks sensitive to OFC dysfunction. [source] A postnatal switch in GABAergic control of spinal cutaneous reflexesEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2006Gareth Hathway Abstract GABAergic signalling exerts powerful inhibitory control over spinal tactile and nociceptive processing, but during development GABA can be depolarizing and the functional consequences of this upon neonatal pain processing is unknown. Here we show a postnatal switch in tonic GABAA receptor (GABAAR) modulation of cutaneous tactile and nociceptive reflexes from excitation to inhibition, but only in the intact spinal cord. Neonatal and 21-day-old (P21) rats were intrathecally treated with one of the GABAAR antagonists bicuculline and gabazine, with both compounds dose-dependently decreasing hindpaw mechanical and thermal withdrawal thresholds in P21 rats but increasing them in P3 neonates. Intrathecal gabazine also produced an increase in the cutaneous evoked electromyography (EMG) response of the biceps femoris in P21 rates but lowering the response in neonates. Injections of 3H-gabazine in the L4,L5 region at P3 confirmed that gabazine binding was restricted to the lumbar spinal cord. Spinalization of P3 neonates at the upper thoracic level prior to drug application reversed the behavioural and EMG responses to GABA antagonists so that they resembled those of P21 rats. The effects of spinalization were consistent with gabazine facilitation of ventral root potentials observed in isolated neonatal spinal cord. These data show a marked postnatal developmental switch in GABAergic control of neonatal nociception that is mediated by supraspinal structures and illustrate the importance of studying developmental circuits in the intact nervous system. [source] Double dissociation of the effects of selective nucleus accumbens core and shell lesions on impulsive-choice behaviour and salience learning in ratsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2005Helen H. J. Pothuizen Abstract The nucleus accumbens can be subdivided into at least two anatomically distinct subregions: a dorsolateral ,core' and a ventromedial ,shell', and this distinction may extend to a functional dissociation. Here, we contrasted the effects of selective excitotoxic core and medial shell lesions on impulsive-choice behaviour using a delayed reward choice paradigm and a differential reward for low rates of responding (DRL) test, against a form of salience learning known as latent inhibition (LI). Core lesions led to enhanced impulsive choices as evidenced by a more pronounced shift from choosing a continuously reinforced lever to a partially reinforced lever, when a delay between lever press and reward delivery was imposed selectively on the former. The core lesions also impaired performance on a DRL task that required withholding the response for a fixed period of time in order to earn a reward. Medial shell lesions had no effect on these two tasks, but abolished the LI effect, as revealed by the failure of stimulus pre-exposure to retard subsequent conditioning to that stimulus in an active avoidance procedure in the lesioned animals. As expected, selective core lesions spared LI. The double dissociations demonstrated here support a functional segregation between nucleus accumbens core and shell, and add weight to the hypothesis that the core, but not the shell, subregion of the nucleus accumbens is preferentially involved in the control of choice behaviour under delayed reinforcement conditions and in the inhibitory control of goal-directed behaviour. [source] Prefrontal-subcortical dissociations underlying inhibitory control revealed by event-related fMRIEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2004A. M. Clare Kelly Abstract Using event-related fMRI, this study investigated the neural dynamics of response inhibition under fluctuating task demands. Fourteen participants performed a GO/NOGO task requiring inhibition of a prepotent motor response to NOGO events that occurred as part of either a Fast or Slow presentation stream of GO stimuli. We compared functional activations associated with correct withholds (Stops) required during the Fast presentation stream of stimuli to Stops required during the Slow presentation stream. A predominantly right hemispheric network was activated across conditions, consistent with previous studies. Furthermore, a functional dissociation of activations between conditions was observed. Slow Stops elicited additional activation in anterior dorsal and polar prefrontal cortex and left inferior parietal cortex. Fast Stops showed additional activation in a network that included right dorsolateral prefrontal cortex, insula and dorsal striatum. These results are discussed in terms of our understanding of the impact of preparation on the distributed network underlying response inhibition and the contribution of subcortical areas, such as the basal ganglia, to executive control processes. [source] Selective GABAergic innervation of thalamic nuclei from zona incertaEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2002P. Barthó Abstract Thalamocortical circuits that govern cortical rhythms and ultimately effect sensory transmission consist of three major interconnected elements: excitatory thalamocortical and corticothalamic neurons and GABAergic cells in the reticular thalamic nucleus. Based on the present results, a fourth component has to be added to this scheme. GABAergic fibres from an extrareticular diencephalic source were found to selectively innervate relay cells located mainly in higher-order thalamic nuclei. The origin of this pathway was localized to zona incerta (ZI), known to receive collaterals from corticothalamic fibres. First-order nuclei were innervated only in zones showing a high density of calbindin-positive neurons. The large GABA-immunoreactive incertal terminals established multiple contacts preferentially on the proximal dendrites of relay cells via symmetrical synapses with multiple release sites. The distribution, ultrastructural characteristics and postsynaptic target selection of extrareticular terminals were similar to type II muscarinic acetylcholine receptor-positive boutons, which constituted up to 49% of all GABAergic terminals in the posterior nucleus. This suggests that a significant proportion of the GABAergic input into certain thalamic territories involved in higher-order functions may have extrareticular origin. Unlike the reticular nucleus, ZI receives peripheral and layer V cortical input but no thalamic feedback; it projects to brainstem centres and has extensive intranuclear recurrent collaterals. This indicates that ZI exerts a conceptually new type of inhibitory control over the thalamus. The proximally situated, multiple active zones of ZI terminals indicate a powerful influence on the firing properties of thalamic neurons, which is conveyed to multiple cortical areas via relay cells which have widespread projections to neocortex. [source] Homeostatic plasticity induced by chronic block of AMPA/kainate receptors modulates the generation of rhythmic bursting in rat spinal cord organotypic culturesEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2001Micaela Galante Abstract Generation of spontaneous rhythmic activity is a distinct feature of developing spinal networks. We report that rat embryo organotypic spinal cultures contain the basic circuits responsible for pattern generation. In this preparation rhythmic activity can be recorded from ventral interneurons and is developmentally regulated. When chronically grown in the presence of an AMPA/kainate receptor blocker, this circuit expresses long-term plasticity consisting largely of increased frequency of fast synaptic activity and reduction in slow GABAergic events. We examined whether, once this form of homeostatic plasticity is established, the network could still exhibit rhythmicity with properties similar to controls. Control or chronically treated ventral interneurons spontaneously generated (with similar probability) irregular, network-driven bursts over a background of ongoing synaptic activity. In control cultures increasing network excitability by strychnine plus bicuculline, or by raising [K+]o, induced rapid-onset, regular rhythmic bursts. In treated cultures the same pharmacological block of Cl, -mediated transmission or high-K+ application also induced regular patterned activity, although significantly faster and, in the case of high K+, characterized by slow onset due to postsynaptic current summation. Enhancing GABAergic transmission by pentobarbital surprisingly accelerated the high-K+ rhythm of control cells (though depressing background activity), whereas it slowed it down in chronically treated cells. This contrasting effect of pentobarbital suggests that, to preserve bursting ability, chronic slices developed a distinct GABAergic inhibitory control on over-expressed bursting circuits. Conversely, in control slices GABAergic transmission depressed spontaneous activity but it facilitated bursting frequency. Thus, even after homeostatic rearrangement, developing mammalian spinal networks still generate rhythmic activity. [source] Anger and Approach Motivation in Infancy: Relations to Early Childhood Inhibitory Control and Behavior ProblemsINFANCY, Issue 3 2010Jie He The relations among infant anger reactivity, approach behavior, and frontal electroencephalogram (EEG) asymmetry, and their relations to inhibitory control and behavior problems in early childhood were examined within the context of a longitudinal study of temperament. Two hundred nine infants' anger expressions to arm restraint were observed at 4 months of age. Infants' approach behaviors during play with an unpredictable toy and baseline frontal EEG asymmetry were assessed at 9 months of age. Inhibitory control during a Go/No-Go task and parent report of behavior problems were evaluated at 4 years of age. High anger-prone infants with left, but not right, frontal EEG asymmetry showed significantly more approach behaviors and less inhibitory control relative to less anger-prone infants. Although a link between anger proneness in infancy and behavior problems in early childhood was not found, a combination of low approach behaviors and poor inhibitory control was predictive of internalizing behaviors. [source] Brain Electrical Activity Associated With Cognitive Processing During a Looking Version of the A-Not-B TaskINFANCY, Issue 3 2001Martha Ann Bell This work was designed to investigate individual differences in brain electrical activity during a looking version of the A-not-B task. It was proposed that this spatial task required the cognitive skills of working memory and inhibitory control, each associated with frontal lobe function. Electroencephalograms (EEGs) were recorded from 54 8-month-old infants during baseline and task. Only high performers on the looking task exhibited increases in 6- to 9-Hz EEG power from baseline to task. These task-related changes were evident at frontal and posterior scalp locations. High performers on the looking task exhibited lower EEG coherence values at right hemisphere frontal locations relative to the low performers. These lower coherence values were evident during baseline and task. All infants showed increased frontal-parietal coherence during the spatial working memory task relative to baseline values. These data confirm previous cognitive neuroscience work associating frontal lobe function with cognitive performance levels during infancy. [source] Performance on Stroop-like assessments of inhibitory control by 4- and 5-year-old childrenINFANT AND CHILD DEVELOPMENT, Issue 3 2010Dave S. Pasalich Abstract The rapid development of an aspect of executive functioning (EF), inhibitory control (IC), between the ages of 3- and 5-years, leads to an increase in a child's capacity to suppress inappropriate responding and therefore activate the necessary resources to carry-out goal-directed activity (Psychological Bulletin, 1997, 121, 65,94). To measure EF in children, tasks administered clinically to adults are adapted. The Day,Night Stroop (DNS) is a pictorial modification of the Stroop Test (Journal of Experimental Psychology, 1935, 18, 642,662), developed for pre-literate children. Although suitable as a measure of IC in 3- to 4-year-old children, ceiling effects have been reported on the DNS in slightly older preschoolers. The present study attempted to overcome this limitation by examining the suitability of two modified versions of the DNS in 4- to 5-year-old preschoolers. To investigate the executive demands made by both Stroop-like tasks, their associations with another measure of IC (stop-signal task) and a measure of working memory were examined. Counter to expectations, no significant association was found in performance between the two Stroop-like tasks; however, the modified DNS developed in this study showed significant relationships with the other executive tasks. The results are discussed in relation to the different methodologies used by these Stroop measures. Implications of this study suggest that researchers should consider more test-specific factors when assessing EF in young children. Copyright © 2010 John Wiley & Sons, Ltd. [source] Temperament at 7, 12, and 25 months in children at familial risk for ADHDINFANT AND CHILD DEVELOPMENT, Issue 4 2008Judith G. Auerbach Abstract As part of a longitudinal investigation of infants at familial risk for attention-deficit hyperactivity disorder (ADHD), mothers and fathers independently completed temperament ratings on their infants. In this paper, we examine the 7-, 12-, and 25-month temperament of 58 boys, 36 of whom were considered at familial risk for ADHD and 22 of whom were in the comparison group. Risk for ADHD was based on self-reported ADHD symptoms in the father. In addition, the influence of informant gender on temperament ratings was examined. The ADHD risk group received significantly higher scores for activity level and anger and lower scores for attentional shift, appropriate allocation of attention and inhibitory control. Their scores were also significantly lower on a composite measure of effortful control. Taken together, these findings offer support for the view of a link between early temperament and risk for ADHD. The only informant gender difference was for the activity level; mothers rated their sons as more active than did fathers. Copyright © 2008 John Wiley & Sons, Ltd. [source] How specific is the relation between executive function and theory of mind?INFANT AND CHILD DEVELOPMENT, Issue 2 2002Contributions of inhibitory control, working memory Abstract The relation between executive function (EF) and theory of mind (ToM) may involve specific processes of inhibition and/or working memory capacity contributing to ToM, or it might be a reflection of general intellectual ability. To differentiate these alternatives, we administered task batteries measuring inhibitory control (IC), working memory, and ToM, as well as measures of verbal and performance intelligence, to 47 typically developing preschool children. Inhibitory control tasks in which a dominant response needed to be suppressed while a subdominant response was activated (Conflict IC) significantly predicted performance on false belief tasks over and above working memory, the intelligence measures, a simple delay task (Delay IC), and age. In contrast, working memory, Delay IC, and intelligence were not significant in this analysis. Conflict IC, but not Delay IC, was related to working memory. Together, these findings suggest that the combination of inhibition and working memory (as reflected in Conflict IC tasks) may be central to the relation between EF and false belief understanding. Copyright © 2002 John Wiley & Sons, Ltd. [source] Young children's difficulty with inhibitory control in a social context,JAPANESE PSYCHOLOGICAL RESEARCH, Issue 2 2008YUSUKE MORIGUCHI Abstract:, The authors' prior research has documented that young children's behaviors in the Dimensional Change Card Sorting (DCCS) task can be influenced by their observation of another person performing the task and has suggested that young children committed perseverative errors in a social context. The present study explored whether children who committed perseverative errors in the social context also committed perseverative errors in the standard DCCS task. Three- and 4-year-old children were given the standard DCCS and the observation version of the DCCS, and the relationship between them was examined. The results showed that the correlation between these two tasks was significant. Furthermore, 4-year-old children displayed more difficulty in the observation version than in the standard DCCS, whereas 3-year-olds did not. The results are discussed in terms of the development of inhibitory control and social cognition. [source] Hostility- and gender-related differences in oscillatory responses to emotional facial expressionsAGGRESSIVE BEHAVIOR, Issue 6 2009Gennady G. Knyazev Abstract Hostility is associated with biases in the perception of emotional facial expressions, such that ambiguous or neutral expressions tend to be perceived as threatening or angry. In this study, the effects of hostility and gender on the perception of angry, neutral, and happy faces and on the oscillatory dynamics of cortical responses elicited by these presentations were investigated using time,frequency decomposition by means of wavelet transforms. Feelings of hostility predisposed subjects to perceive happy and neutral faces as less friendly. This effect was more pronounced in women. In hostile subjects, presentation of emotional facial expressions also evoked stronger posterior synchronization in the theta and diminished desynchronization in the alpha band. This may signify a prevalence of emotional responding over cognitive processing. These effects were also more pronounced in females. Hostile females, but not hostile males, additionally showed a widespread synchronization in the alpha band. This synchronization is tentatively explained as a manifestation of inhibitory control which is present in aggressive females, but not in aggressive males. Aggr. Behav. 35:502,513, 2009. © 2009 Wiley-Liss, Inc. [source] | ||||||||||||||||