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Motor Behavior (motor + behavior)
Kinds of Motor Behavior Selected AbstractsOn functional motor adaptations: from the quantification of motor strategies to the prevention of musculoskeletal disorders in the neck,shoulder regionACTA PHYSIOLOGICA, Issue 2010P. Madeleine Abstract Background:, Occupations characterized by a static low load and by repetitive actions show a high prevalence of work-related musculoskeletal disorders (WMSD) in the neck,shoulder region. Moreover, muscle fatigue and discomfort are reported to play a relevant initiating role in WMSD. Aims: To investigate relationships between altered sensory information, i.e. localized muscle fatigue, discomfort and pain and their associations to changes in motor control patterns. Materials & Methods:, In total 101 subjects participated. Questionnaires, subjective assessments of perceived exertion and pain intensity as well as surface electromyography (SEMG), mechanomyography (MMG), force and kinematics recordings were performed. Results:, Multi-channel SEMG and MMG revealed that the degree of heterogeneity of the trapezius muscle activation increased with fatigue. Further, the spatial organization of trapezius muscle activity changed in a dynamic manner during sustained contraction with acute experimental pain. A graduation of the motor changes in relation to the pain stage (acute, subchronic and chronic) and work experience were also found. The duration of the work task was shorter in presence of acute and chronic pain. Acute pain resulted in decreased activity of the painful muscle while in subchronic and chronic pain, a more static muscle activation was found. Posture and movement changed in the presence of neck,shoulder pain. Larger and smaller sizes of arm and trunk movement variability were respectively found in acute pain and subchronic/chronic pain. The size and structure of kinematics variability decreased also in the region of discomfort. Motor variability was higher in workers with high experience. Moreover, the pattern of activation of the upper trapezius muscle changed when receiving SEMG/MMG biofeedback during computer work. Discussion:, SEMG and MMG changes underlie functional mechanisms for the maintenance of force during fatiguing contraction and acute pain that may lead to the widespread pain seen in WMSD. A lack of harmonious muscle recruitment/derecruitment may play a role in pain transition. Motor behavior changed in shoulder pain conditions underlining that motor variability may play a role in the WMSD development as corroborated by the changes in kinematics variability seen with discomfort. This prognostic hypothesis was further, supported by the increased motor variability among workers with high experience. Conclusion:, Quantitative assessments of the functional motor adaptations can be a way to benchmark the pain status and help to indentify signs indicating WMSD development. Motor variability is an important characteristic in ergonomic situations. Future studies will investigate the potential benefit of inducing motor variability in occupational settings. [source] The dusp1 immediate early gene is regulated by natural stimuli predominantly in sensory input neuronsTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 14 2010Haruhito Horita Abstract Many immediate early genes (IEGs) have activity-dependent induction in a subset of brain subdivisions or neuron types. However, none have been reported yet with regulation specific to thalamic-recipient sensory neurons of the telencephalon or in the thalamic sensory input neurons themselves. Here, we report the first such gene, dual specificity phosphatase 1 (dusp1). Dusp1 is an inactivator of mitogen-activated protein kinase (MAPK), and MAPK activates expression of egr1, one of the most commonly studied IEGs, as determined in cultured cells. We found that in the brain of naturally behaving songbirds and other avian species, hearing song, seeing visual stimuli, or performing motor behavior caused high dusp1 upregulation, respectively, in auditory, visual, and somatosensory input cell populations of the thalamus and thalamic-recipient sensory neurons of the telencephalic pallium, whereas high egr1 upregulation occurred only in subsequently connected secondary and tertiary sensory neuronal populations of these same pathways. Motor behavior did not induce high levels of dusp1 expression in the motor-associated areas adjacent to song nuclei, where egr1 is upregulated in response to movement. Our analysis of dusp1 expression in mouse brain suggests similar regulation in the sensory input neurons of the thalamus and thalamic-recipient layer IV and VI neurons of the cortex. These findings suggest that dusp1 has specialized regulation to sensory input neurons of the thalamus and telencephalon; they further suggest that this regulation may serve to attenuate stimulus-induced expression of egr1 and other IEGs, leading to unique molecular properties of forebrain sensory input neurons. J. Comp. Neurol. 518:2873,2901, 2010. © 2010 Wiley-Liss, Inc. [source] The neuroanatomy and neuroendocrinology of fragile X syndromeDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 1 2004David Hessl Abstract Fragile X syndrome (FXS), caused by a single gene mutation on the X chromosome, offers a unique opportunity for investigation of gene,brain,behavior relationships. Recent advances in molecular genetics, human brain imaging, and behavioral studies have started to unravel the complex pathways leading to the cognitive, psychiatric, and physical features that are unique to this syndrome. In this article, we summarize studies focused on the neuroanatomy and neuroendocrinology of FXS. A review of structural imaging studies of individuals with the full mutation shows that several brain regions are enlarged, including the hippocampus, amygdala, caudate nucleus, and thalamus, even after controlling for overall brain volume. These regions mediate several cognitive and behavioral functions known to be aberrant in FXS such as memory and learning, information and sensory processing, and social and emotional behavior. Two regions, the cerebellar vermis, important for a variety of cognitive tasks and regulation of motor behavior, and the superior temporal gyrus, involved in processing complex auditory stimuli, are reported to be reduced in size relative to controls. Functional imaging, typically limited to females, has emphasized that individuals with FXS do not adequately recruit brain regions that are normally utilized by unaffected individuals to carry out various cognitive tasks, such as arithmetic processing or visual memory tasks. Finally, we review a number of neuroendocrine studies implicating hypothalamic dysfunction in FXS, including abnormal activation of the hypothalamic,pituitary,adrenal (HPA) axis. These studies may help to explain the abnormal stress responses, sleep abnormalities, and physical growth patterns commonly seen in affected individuals. In the future, innovative longitudinal studies to investigate development of neurobiologic and behavioral features over time, and ultimately empirical testing of pharmacological, behavioral, and even molecular genetic interventions using MRI are likely to yield significant positive changes in the lives of persons with FXS, as well as increase our understanding of the development of psychiatric and learning problems in the general population. MRDD Research Reviews 2004;10:17,24. © 2004 Wiley-Liss, Inc. [source] Conjugate limb coordination after experience with an interlimb yoke: Evidence for motor learning in the rat fetusDEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2005Scott R. Robinson Abstract This study investigated the capacity of the E20 rat fetus to adaptively alter patterns of interlimb coordination in a prenatal model of motor learning. Fetal limb movement was manipulated with an interlimb yoke, consisting of a fine thread attached at the ankles, which created a physical linkage between two limbs. Exposure to the yoke resulted in a gradual increase in conjugate movements of the yoked limbs during a 30-min training period, which persisted after removal of the yoke. Training effects were evident when the yoke was applied to two hindlimbs, two forelimbs, or a homolateral forelimb,hindlimb pair. A savings in the rate of acquisition also was observed when fetuses experienced yoke training in a second session. These data argue that the rat fetus can respond to kinesthetic feedback resulting from variation in motor performance, which suggests that experience contributes to the development of coordinated motor behavior before birth. © 2005 Wiley Periodicals, Inc. Dev Psychobiol 47: 328,344, 2005. [source] Effect of Ganaxolone on Flurothyl Seizures in Developing RatsEPILEPSIA, Issue 7 2000a Liptáková Summary: Purpose: To determine the effects of a newly synthesized epalon, ganaxolone (GNX), on primarily generalized seizures in rats of various ages during development. Epalons are classified as neuroactive steroids that interact at unique site of the GABAA receptor-Cl, channel complex in the central nervous system. Methods: Sprague-Dawley male rats were used at 9, 15, 30, and 60 postnatal days (PN). GNX dissolved in 2-hydroxypropyl-,-cyclodextrine was administered intraperitoneally in different doses at various time points before flurothyl testing. The incidence and threshold of clonic and tonic-clonic flurothyl seizures were evaluated. Behavioral changes were also assessed. Results: In all age groups, the effects of GNX were dose dependent and more prominent 10 min after its administration. In PN 60 and PN 30 rats, GNX had dose-dependent anticon-vulsant effects; tonic-clonic seizures were more sensitive to GNX treatment than clonic seizures. In PN 15 and PN 9 rats, GNX demonstrated dose- and time-dependent anticonvulsant effects against both types of flurothyl-induced seizures. GNX was more effective in PN 15 rats than in other age groups, but at doses that altered motor behavior. Conclusions: GNX has anticonvulsant effects against flurothyl-induced seizures in all age groups tested. Its effects are more prominent in the two younger age groups, especially in PN 15 rats, but are associated with motor side effects. [source] Inter-hemispheric inhibition is impaired in mirror dystoniaEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 8 2009S. Beck Abstract Surround inhibition, a neural mechanism relevant for skilled motor behavior, has been shown to be deficient in the affected primary motor cortex (M1) in patients with focal hand dystonia (FHD). Even in unilateral FHD, however, electrophysiological and neuroimaging studies have provided evidence for bilateral M1 abnormalities. Clinically, the presence of mirror dystonia, dystonic posturing when the opposite hand is moved, also suggests abnormal interhemispheric interaction. To assess whether a loss of inter-hemispheric inhibition (IHI) may contribute to the reduced surround inhibition, IHI towards the affected or dominant M1 was examined in 13 patients with FHD (seven patients with and six patients without mirror dystonia, all affected on the right hand) and 12 right-handed, age-matched healthy controls (CON group). IHI was tested at rest and during three different phases of a right index finger movement in a synergistic, as well as in a neighboring, relaxed muscle. There was a trend for a selective loss of IHI between the homologous surrounding muscles in the phase 50 ms before electromyogram onset in patients with FHD. Post hoc analysis revealed that this effect was due to a loss of IHI in the patients with FHD with mirror dystonia, while patients without mirror dystonia did not show any difference in IHI modulation compared with healthy controls. We conclude that mirror dystonia may be due to impaired IHI towards neighboring muscles before movement onset. However, IHI does not seem to play a major role in the general pathophysiology of FHD. [source] The pallial basal ganglia pathway modulates the behaviorally driven gene expression of the motor pathwayEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2007Lubica Kubikova Abstract The discrete neural network for songbird vocal communication provides an effective system to study neural mechanisms of learned motor behaviors in vertebrates. This system consists of two pathways , a vocal motor pathway used to produce learned vocalizations and a vocal pallial basal ganglia loop used to learn and modify the vocalizations. However, it is not clear how the loop exerts control over the motor pathway. To study the mechanism, we used expression of the neural activity-induced gene ZENK (or egr-1), which shows singing-regulated expression in a social context-dependent manner: high levels in both pathways when singing undirected and low levels in the lateral part of the loop and in the robust nucleus of the arcopallium (RA) of the motor pathway when singing directed to another animal. Here, we show that there are two parallel interactive parts within the pallial basal ganglia loop, lateral and medial, which modulate singing-driven ZENK expression of the motor pathway nuclei RA and HVC, respectively. Within the loop, the striatal and pallial nuclei appear to have opposing roles; the striatal vocal nucleus lateral AreaX is required for high ZENK expression in its downstream nuclei, particularly during undirected singing, while the pallial vocal lateral magnocellular nucleus of the anterior nidopallium is required for lower expression, particularly during directed singing. These results suggest a dynamic molecular interaction between the basal ganglia pathway and the motor pathway during production of a learned motor behavior. [source] Behavioral and neurochemical phenotyping of Homer1 mutant mice: possible relevance to schizophreniaGENES, BRAIN AND BEHAVIOR, Issue 5 2005K. K. Szumlinski Homer proteins are involved in the functional assembly of postsynaptic density proteins at glutamatergic synapses and are implicated in learning, memory and drug addiction. Here, we report that Homer1 -knockout (Homer1 -KO) mice exhibit behavioral and neurochemical abnormalities that are consistent with the animal models of schizophrenia. Relative to wild-type mice, Homer1 -KO mice exhibited deficits in radial arm maze performance, impaired prepulse inhibition, enhanced ,behavioral despair', increased anxiety in a novel objects test, enhanced reactivity to novel environments, decreased instrumental responding for sucrose and enhanced MK-801- and methamphetamine-stimulated motor behavior. No-net-flux in vivo microdialysis revealed a decrease in extracellular glutamate content in the nucleus accumbens and an increase in the prefrontal cortex. Moreover, in Homer1 -KO mice, cocaine did not stimulate a rise in frontal cortex extracellular glutamate levels, suggesting hypofrontality. These behavioral and neurochemical data derived from Homer1 mutant mice are consistent with the recent association of schizophrenia with a single-nucleotide polymorphism in the Homer1 gene and suggest that the regulation of extracellular levels of glutamate within limbo-corticostriatal structures by Homer1 gene products may be involved in the pathogenesis of this neuropsychiatric disorder. [source] Risk factors for neuropsychiatric symptoms in dementia: the Cache County StudyINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 9 2006M. Steinberg Abstract Objective To investigate the probability of individual neuropsychiatric symptoms in dementia patients as a function of eight risk factors. Methods In the Cache County Study, we administered the Neuropsychiatric Inventory (NPI) to 328 dementia patients at baseline. Approximately 18 months later, we re-administered the NPI to 184 participants available for follow-up. Generalized estimating equation methods were used to model the probability of individual neuropsychiatric symptoms as a function of: gender, age, education, dementia type and severity, APOE status, time of observation, and general medical health. Results Women showed increased tendency toward anxiety, [odds ratio (OR) 2.22, 95% confidence interval (CI) 1.31,3.76] and delusions (OR 2.15, CI 1.22,3.78), but older persons of both sexes showed less tendency toward anxiety. Dementia severity increased the tendency toward hallucinations and agitation (OR 2.42, CI 1.81,3.23) and decreased risk of depression. Positive APOE ,4 status increased the tendency toward aberrant motor behavior (OR 1.84, CI 1.05,3.22). Among dementia diagnoses, those with Alzheimer's disease showed decreased tendency toward agitation (OR 0.58, CI 0.35,0.95), depression (OR 0.56, CI 0.33,0.96) and disinhibition (OR 0.46, CI 0.24,0.88). Later time of observation increased risk of aberrant motor behavior and delusions, and more serious medical comorbidity increased risk of, agitation, irritability, disinhibition, and aberrant motor behavior. Conclusions Gender, age, dementia severity, APOE ,4, dementia diagnosis, time of observation, and general medical health appear to influence the occurrence of individual neuropsychiatric symptoms. Copyright © 2006 John Wiley & Sons, Ltd. [source] 5-HT2A T102C receptor polymorphism and neuropsychiatric symptoms in Alzheimer's diseaseINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 6 2004Linda Chiu Wa Lam Abstract Objective To investigate the association between 5-HT2A receptor polymorphism and neuropsychiatric (NP) symptoms in Chinese elderly with Alzheimer's disease (AD). Methods This case-control study evaluated Chinese subjects with AD first presented to an university affiliated psychogeriatric clinic. Eighty-seven subjects with NINCDS-ADRDA diagnosis for probable and possible AD were recruited consecutively from the psychogeriatric clinics of the Prince of Wales Hospital in Hong Kong. 5-HT2A receptor polymorphisms were examined by polymerase chain reaction (PCR), enzyme digestion and gel electrophoresis. NP symptoms were assessed by the Chinese version of the Neuropsychiatric Inventory (NPI). Results The genotype frequencies were significantly different in subjects with regards to the presentation of delusions, aggression, aberrant motor behavior and apathy (Pearson Chi Squares, p,<,0.05). If only homozygote states were included, there were significantly fewer subjects of CC genotype with delusion (Pearson chi square, p,<,0.05). Conclusions Specific NP symptoms in AD were significantly associated with 5-HT2A receptor polymorphisms. Possible ethnic differences in the behavioral expression of 5-HT2A receptor polymorphisms are worthy of further exploration. Copyright © 2004 John Wiley & Sons, Ltd. [source] The persistence of neuropsychiatric symptoms in dementia: the Cache County StudyINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 1 2004Martin Steinberg Abstract Objective To estimate the 18-month persistence of neuropsychiatric symptoms in dementia in a population-based sample, and to compare the severity of neuropsychiatric symptoms at baseline to the severity at 18-month follow-up. Methods A population-based sample of 329 residents of Cache County, Utah, diagnosed with dementia was rated on the Neuropsychiatric Inventory (NPI). Of the 204 participants with neuropsychiatric symptoms at baseline (defined as total NPI score >0), NPI data were obtained approximately 18 months later on 117 who were alive and available for follow-up. Results Eighty-one percent of those with neuropsychiatric symptoms at baseline (defined as total NPI score>0) continued to have at least one symptom at follow-up. Sixty-seven percent of participants with a clinically significant total NPI score (defined as ,;4) at baseline continued to have a clinically significant total NPI score at follow-up. Among the ten neuropsychiatric domains assessed at baseline, delusions persisted in 65.5% of individuals, followed by depression (58.3%), and aberrant motor behavior (55.6%), while hallucinations and disinhibition persisted in only 25.0% and 11.1% respectively. In participants who were symptomatic at both baseline and follow-up, the mean severity scores at the two observation points were comparable in all ten neuropsychiatric domains. Conclusions Neuropsychiatric symptoms in dementia overall were highly persistent. Among those in whom symptoms did persist, symptom severity a year and a half later appeared to be comparable. Copyright © 2004 John Wiley & Sons, Ltd. [source] Providing Nutrition Supplements to Institutionalized Seniors with Probable Alzheimer's Disease Is Least Beneficial to Those with Low Body Weight StatusJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 8 2004Karen W. H. Young MSc Objectives: To examine whether providing a midmorning nutrition supplement increases habitual energy intake in seniors with probable Alzheimer's disease (AD) and to investigate the effects of body weight status and cognitive and behavioral function on the response to the intervention. Design: Randomized, crossover, nonblinded clinical trial. Setting: A fully accredited geriatric teaching facility affiliated with the University of Toronto's Medical School with a home for the aged. Participants: Thirty-four institutionalized seniors with probable AD who ate independently. Intervention: Nutrition supplements were provided between breakfast and lunch for 21 consecutive days and compared with 21 consecutive days of habitual intake. Measurements: Investigator-weighed food intake, body weight, cognitive function (Severe Impairment Battery and Global Deterioration Scale), behavioral disturbances (Neuropsychiatric Inventory,Nursing Home Version), and behavioral function (London Psychogeriatric Rating Scale). Results: Relative to habitual intake, group mean analyses showed increased 24-hour energy, protein, and carbohydrate intake during the supplement phase, but five of 31 subjects who finished all study phases completely compensated for the energy provided by the supplement by reducing lunch intake, and 24-hour energy intake was enhanced in only 21 of 31 subjects. Compensation at lunch was more likely in subjects with lower body mass indices, increased aberrant motor behavior, poorer attention, and increased mental disorganization/confusion. Conclusion: Nutrition supplements were least likely to enhance habitual energy intake in subjects who would normally be targeted for nutrition intervention,those with low body weight status. Those likely to benefit include those with higher body mass indices, less aberrant motor problems, less mental disorganization, and increased attention. [source] Frontal cortical afferents facilitate striatal nitric oxide transmission in vivo via a NMDA receptor and neuronal NOS-dependent mechanismJOURNAL OF NEUROCHEMISTRY, Issue 3 2007Stephen Sammut Abstract Striatal nitric oxide (NO) signaling plays a critical role in modulating neural processing and motor behavior. Nitrergic interneurons receive synaptic inputs from corticostriatal neurons and are activated via ionotropic glutamate receptor stimulation. However, the afferent regulation of NO signaling is poorly characterized. The role of frontal cortical afferents in regulating NO transmission was assessed in anesthetized rats using amperometric microsensor measurements of NO efflux and local field potential recordings. Low frequency (3 Hz) electrical stimulation of the ipsilateral cortex did not consistently evoke detectable changes in striatal NO efflux. In contrast, train stimulation (30 Hz) of frontal cortical afferents facilitated NO efflux in a stimulus intensity-dependent manner. Nitric oxide efflux evoked by train stimulation was transient, reproducible over time, and attenuated by systemic administration of either the NMDA receptor antagonist MK-801 or the neuronal NO synthase inhibitors 7-nitroindazole and NG -propyl- l -arginine. The interaction between NO efflux evoked via train stimulation and local striatal neuron activity was assessed using dual microsensor and local field potential recordings carried out concurrently in the contralateral and ipsilateral striatum, respectively. Systemic administration of the non-specific NO synthase inhibitor methylene blue attenuated both evoked NO efflux and the peak oscillation frequency (within the delta band) of local field potentials recorded immediately after train stimulation. Taken together, these observations indicate that feed-forward activation of neuronal NO signaling by phasic activation of frontal cortical afferents facilitates the synchronization of glutamate driven oscillations in striatal neurons. Thus, NO signaling may act to amplify coherent corticostriatal transmission and synchronize striatal output. [source] Behavioral and electrophysiological effects of 5-HT in globus pallidus of 6-hydroxydopamine lesioned ratsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 7 2010Shu-Jing Zhang Abstract Anatomical studies have shown that the globus pallidus receives abundant 5-hydroxytryptamine (5-HT) innervations from raphe nuclei. 5-HT may occupy an important position in the modulation of motor function through its affect on the activity of globus pallidus. In the present study, intrapallidal microinjection of 5-HT (0.1 mM) alone did not induce any motor behavior or postural asymmetry in the unilateral 6-hydroxydopamine (6-OHDA)-lesioned rats. However, when infused concomitantly with a low dose of 3, 4-dihydroxyphenylalanine (L-DOPA, 3 mg/kg i.p.), which itself can induce modest contralateral rotational behavior, 5-HT significantly potentiated the number of contralateral rotations. To elucidate the cellular mechanism, in vivo extracellular recordings were performed to examine the effects of 5-HT on globus pallidus neurons. In normal rats, the predominant effect of micropressure ejection of 5-HT on pallidal neurons was excitation. In 6-OHDA-lesioned rats, although 5-HT increased the firing rate in most pallidal neurons, 5-HT-induced inhibitory effects was stronger than that on the unlesioned side as well as normal rats. Furthermore, 5-HT1B receptors are mainly involved in 5-HT-induced excitation while 5-HT1A receptors are involved in 5-HT-induced inhibition. The results suggest that 5-HT may potentiate the antiparkinsonian effect of L-DOPA through modulating the activity of globus pallidus. © 2009 Wiley-Liss, Inc. [source] Guanosine improves motor behavior, reduces apoptosis, and stimulates neurogenesis in rats with parkinsonismJOURNAL OF NEUROSCIENCE RESEARCH, Issue 3 2009Caixin Su Abstract Parkinson's disease (PD) is characterized by progressive degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNc) caused by an abnormal rate of apoptosis. Endogenous stem cells in the adult mammalian brain indicate an innate potential for regeneration and possible resource for neuroregeneration in PD. We previously showed that guanosine prevents apoptosis even when administered 48 hr after the toxin 1-methyl-4-phenylpyridinium (MPP+). Here, we induced parkinsonism in rats with a proteasome inhibitor. Guanosine treatment reduced apoptosis, increased tyrosine hydroxylase,positive dopaminergic neurons and expression of tyrosine hydroxylase in the SNc, increased cellular proliferation in the SNc and subventricular zone, and ameliorated symptoms. Proliferating cells in the subventricular zone were nestin-positive adult neural progenitor/stem cells. Fibroblast growth factor-2-expressing cells were also increased by guanosine. Thus, guanosine protected cells from apoptosis and stimulated "intrinsic" adult progenitor/stem cells to become dopaminergic neurons in rats with proteasome inhibitor,induced PD. The cellular/molecular mechanisms underlying these effects may open new avenues for development of novel therapeutics for PD. © 2008 Wiley-Liss, Inc. [source] Individual Differences in Approach and Avoidance Movements: How the Avoidance Motive Influences Response ForceJOURNAL OF PERSONALITY, Issue 4 2006Rosa Maria Puca ABSTRACT The present research is based on the assumption that people differ in their responsiveness to incentives and threats. In two experiments we examined whether the trait corresponding to the responsiveness to threats (avoidance motive) and the trait corresponding to the responsiveness to incentives (approach motive) influence voluntary motor behavior toward or away from stimuli. In Experiment 1, stimuli consisted of positive and negative words within a lexical decision task. Participants moved their arms backward in order to withdraw from the stimuli or forward in order to approach them. In Experiment 2, participants responded with forward or backward arm movements to neutral sounds coming from behind or in front of them. The main dependent variable was the strength of the approach and avoidance movements. In both experiments this variable was related to participants' avoidance-motive disposition but not to their approach-motive disposition. Avoidance-motivated individuals generally showed more forceful avoidance movements than approach movements. There was no effect of stimulus valence on the strength of the movements in Experiment 1. Furthermore, the results of Experiment 2 suggest that it is not the physical direction (forward or backward) but rather the movement's effect of distance reduction (approach) or distance increase (avoidance) in regard to the stimulus that defines a movement as an approach or an avoidance movement. [source] Disruptions in Functional Network Connectivity During Alcohol Intoxicated DrivingALCOHOLISM, Issue 3 2010Catherine I. Rzepecki-Smith Background:, Driving while under the influence of alcohol is a major public health problem whose neural basis is not well understood. In a recently published functional magnetic resonance imaging (fMRI) study (Meda et al., 2009), our group identified 5, independent critical driving-associated brain circuits whose inter-regional connectivity was disrupted by alcohol intoxication. However, the functional connectivity between these circuits has not yet been explored in order to determine how these networks communicate with each other during sober and alcohol-intoxicated states. Methods:, In the current study, we explored such differences in connections between the above brain circuits and driving behavior, under the influence of alcohol versus placebo. Forty social drinkers who drove regularly underwent fMRI scans during virtual reality driving simulations following 2 alcohol doses, placebo and an individualized dose producing blood alcohol concentrations (BACs) of 0.10%. Results:, At the active dose, we found specific disruptions of functional network connectivity between the frontal-temporal-basal ganglia and the cerebellar circuits. The temporal connectivity between these 2 circuits was found to be less correlated (p < 0.05) when driving under the influence of alcohol. This disconnection was also associated with an abnormal driving behavior (unstable motor vehicle steering). Conclusions:, Connections between frontal-temporal-basal ganglia and cerebellum have recently been explored; these may be responsible in part for maintaining normal motor behavior by integrating their overlapping motor control functions. These connections appear to be disrupted by alcohol intoxication, in turn associated with an explicit type of impaired driving behavior. [source] Redefining functional models of basal ganglia organization: Role for the posteroventral pallidum in linguistic processing?MOVEMENT DISORDERS, Issue 11 2004Brooke-Mai Whelan PhD Abstract Traditionally the basal ganglia have been implicated in motor behavior, as they are involved in both the execution of automatic actions and the modification of ongoing actions in novel contexts. Corresponding to cognition, the role of the basal ganglia has not been defined as explicitly. Relative to linguistic processes, contemporary theories of subcortical participation in language have endorsed a role for the globus pallidus internus (GPi) in the control of lexical,semantic operations. However, attempts to empirically validate these postulates have been largely limited to neuropsychological investigations of verbal fluency abilities subsequent to pallidotomy. We evaluated the impact of bilateral posteroventral pallidotomy (BPVP) on language function across a range of general and high-level linguistic abilities, and validated/extended working theories of pallidal participation in language. Comprehensive linguistic profiles were compiled up to 1 month before and 3 months after BPVP in 6 subjects with Parkinson's disease (PD). Commensurate linguistic profiles were also gathered over a 3-month period for a nonsurgical control cohort of 16 subjects with PD and a group of 16 non-neurologically impaired controls (NC). Nonparametric between-groups comparisons were conducted and reliable change indices calculated, relative to baseline/3-month follow-up difference scores. Group-wise statistical comparisons between the three groups failed to reveal significant postoperative changes in language performance. Case-by-case data analysis relative to clinically consequential change indices revealed reliable alterations in performance across several language variables as a consequence of BPVP. These findings lend support to models of subcortical participation in language, which promote a role for the GPi in lexical,semantic manipulation mechanisms. Concomitant improvements and decrements in postoperative performance were interpreted within the context of additive and subtractive postlesional effects. Relative to parkinsonian cohorts, clinically reliable versus statistically significant changes on a case by case basis may provide the most accurate method of characterizing the way in which pathophysiologically divergent basal ganglia linguistic circuits respond to BPVP. © 2004 Movement Disorder Society [source] The dusp1 immediate early gene is regulated by natural stimuli predominantly in sensory input neuronsTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 14 2010Haruhito Horita Abstract Many immediate early genes (IEGs) have activity-dependent induction in a subset of brain subdivisions or neuron types. However, none have been reported yet with regulation specific to thalamic-recipient sensory neurons of the telencephalon or in the thalamic sensory input neurons themselves. Here, we report the first such gene, dual specificity phosphatase 1 (dusp1). Dusp1 is an inactivator of mitogen-activated protein kinase (MAPK), and MAPK activates expression of egr1, one of the most commonly studied IEGs, as determined in cultured cells. We found that in the brain of naturally behaving songbirds and other avian species, hearing song, seeing visual stimuli, or performing motor behavior caused high dusp1 upregulation, respectively, in auditory, visual, and somatosensory input cell populations of the thalamus and thalamic-recipient sensory neurons of the telencephalic pallium, whereas high egr1 upregulation occurred only in subsequently connected secondary and tertiary sensory neuronal populations of these same pathways. Motor behavior did not induce high levels of dusp1 expression in the motor-associated areas adjacent to song nuclei, where egr1 is upregulated in response to movement. Our analysis of dusp1 expression in mouse brain suggests similar regulation in the sensory input neurons of the thalamus and thalamic-recipient layer IV and VI neurons of the cortex. These findings suggest that dusp1 has specialized regulation to sensory input neurons of the thalamus and telencephalon; they further suggest that this regulation may serve to attenuate stimulus-induced expression of egr1 and other IEGs, leading to unique molecular properties of forebrain sensory input neurons. J. Comp. Neurol. 518:2873,2901, 2010. © 2010 Wiley-Liss, Inc. [source] A new microswitch to enable a boy with minimal motor behavior to control environmental stimulation with eye blinksBEHAVIORAL INTERVENTIONS, Issue 2 2005Giulio E. Lancioni This study assessed whether a boy with profound multiple disabilities and minimal motor behavior would be able to control environmental stimulation using repeated eye blinks with a newly developed microswitch (i.e. an electronically regulated optic sensor mounted on an eyeglasses frame). The study was carried out according to an ABAB design and included a 3 month post-intervention check. Data showed that the boy had a large increase in the target response (repeated eye blinks) to activate the microswitch and produce environmental stimulation during the B (intervention) phases. This performance was maintained at the post-intervention check. Practical and developmental implications of the findings were discussed. Copyright © 2005 John Wiley & Sons, Ltd. [source] Animal Foraging and the Evolution of Goal-Directed CognitionCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 1 2006Thomas T. Hills Abstract Foraging- and feeding-related behaviors across eumetazoans share similar molecular mechanisms, suggesting the early evolution of an optimal foraging behavior called area-restricted search (ARS), involving mechanisms of dopamine and glutamate in the modulation of behavioral focus. Similar mechanisms in the vertebrate basal ganglia control motor behavior and cognition and reveal an evolutionary progression toward increasing internal connections between prefrontal cortex and striatum in moving from amphibian to primate. The basal ganglia in higher vertebrates show the ability to transfer dopaminergic activity from unconditioned stimuli to conditioned stimuli. The evolutionary role of dopamine in the modulation of goal-directed behavior and cognition is further supported by pathologies of human goal-directed cognition, which have motor and cognitive dysfunction and organize themselves, with respect to dopaminergic activity, along the gradient described by ARS, from perseverative to unfocused. The evidence strongly supports the evolution of goal-directed cognition out of mechanisms initially in control of spatial foraging but, through increasing cortical connections, eventually used to forage for information. [source] Glutamate drives the touch response through a rostral loop in the spinal cord of zebrafish embryosDEVELOPMENTAL NEUROBIOLOGY, Issue 12 2009Thomas Pietri Abstract Characterizing connectivity in the spinal cord of zebrafish embryos is not only prerequisite to understanding the development of locomotion, but is also necessary for maximizing the potential of genetic studies of circuit formation in this model system. During their first day of development, zebrafish embryos show two simple motor behaviors. First, they coil their trunks spontaneously, and a few hours later they start responding to touch with contralateral coils. These behaviors are contemporaneous until spontaneous coils become infrequent by 30 h. Glutamatergic neurons are distributed throughout the embryonic spinal cord, but their contribution to these early motor behaviors in immature zebrafish is still unclear. We demonstrate that the kinetics of spontaneous coiling and touch-evoked responses show distinct developmental time courses and that the touch response is dependent on AMPA-type glutamate receptor activation. Transection experiments suggest that the circuits required for touch-evoked responses are confined to the spinal cord and that only the most rostral part of the spinal cord is sufficient for triggering the full response. This rostral sensory connection is presumably established via CoPA interneurons, as they project to the rostral spinal cord. Electrophysiological analysis demonstrates that these neurons receive short latency AMPA-type glutamatergic inputs in response to ipsilateral tactile stimuli. We conclude that touch responses in early embryonic zebrafish arise only after glutamatergic synapses connect sensory neurons and interneurons to the contralateral motor network via a rostral loop. This helps define an elementary circuit that is modified by the addition of sensory inputs, resulting in behavioral transformation. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2009 [source] The pallial basal ganglia pathway modulates the behaviorally driven gene expression of the motor pathwayEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2007Lubica Kubikova Abstract The discrete neural network for songbird vocal communication provides an effective system to study neural mechanisms of learned motor behaviors in vertebrates. This system consists of two pathways , a vocal motor pathway used to produce learned vocalizations and a vocal pallial basal ganglia loop used to learn and modify the vocalizations. However, it is not clear how the loop exerts control over the motor pathway. To study the mechanism, we used expression of the neural activity-induced gene ZENK (or egr-1), which shows singing-regulated expression in a social context-dependent manner: high levels in both pathways when singing undirected and low levels in the lateral part of the loop and in the robust nucleus of the arcopallium (RA) of the motor pathway when singing directed to another animal. Here, we show that there are two parallel interactive parts within the pallial basal ganglia loop, lateral and medial, which modulate singing-driven ZENK expression of the motor pathway nuclei RA and HVC, respectively. Within the loop, the striatal and pallial nuclei appear to have opposing roles; the striatal vocal nucleus lateral AreaX is required for high ZENK expression in its downstream nuclei, particularly during undirected singing, while the pallial vocal lateral magnocellular nucleus of the anterior nidopallium is required for lower expression, particularly during directed singing. These results suggest a dynamic molecular interaction between the basal ganglia pathway and the motor pathway during production of a learned motor behavior. [source] Unidirectional startle responses and disrupted left,right co-ordination of motor behaviors in robo3 mutant zebrafishGENES, BRAIN AND BEHAVIOR, Issue 5 2009H. A. Burgess The Roundabout (Robo) family of receptors and their Slit ligands play well-established roles in axonal guidance, including in humans where horizontal gaze palsy with progressive scoliosis (HGPPS) is caused by mutations in the robo3 gene. Although significant progress has been made toward understanding the mechanism by which Robo receptors establish commissural projections in the central nervous system, less is known about how these projections contribute to neural circuits mediating behavior. In this study, we report cloning of the zebrafish behavioral mutant twitch twice and show that twitch twice encodes robo3. We show that in mutant hindbrains the axons of an identified pair of neurons, the Mauthner cells, fail to cross the midline. The Mauthner neurons are essential for the startle response, and in twitch twice/robo3 mutants misguidance of the Mauthner axons results in a unidirectional startle response. Moreover, we show that twitch twice mutants exhibit normal visual acuity but display defects in horizontal eye movements, suggesting a specific and critical role for twitch twice/robo3 in sensory-guided behavior. [source] Rhythmic movement disorder (head banging) in an adult during rapid eye movement sleepMOVEMENT DISORDERS, Issue 6 2006Kirstie N. Anderson MD Abstract Sleep-related rhythmic movements (head banging or body rocking) are extremely common in normal infants and young children, but less than 5% of children over the age of 5 years old exhibit these stereotyped motor behaviors. They characteristically occur during drowsiness or sleep onset rather than in deep sleep or rapid eye movement (REM) sleep. We present a 27-year-old man with typical rhythmic movement disorder that had persisted into adult life and was restricted to REM sleep. This man is the oldest subject with this presentation reported to date and highlights the importance of recognizing this nocturnal movement disorder when it does occur in adults. © 2006 Movement Disorder Society [source] Familial associations of intense preoccupations, an empirical factor of the restricted, repetitive behaviors and interests domain of autismTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 8 2009Christopher J. Smith Background:, Clinical heterogeneity of autism likely hinders efforts to find genes associated with this complex psychiatric disorder. Some studies have produced promising results by restricting the sample according to the expression of specific familial factors or components of autism. Previous factor analyses of the restricted, repetitive behaviors and interest (RRBI) domain of autism have consistently identified a two-factor model that explains a moderate amount of variance. The identification of additional factors may explain more variance in the RRBI domain and provide an additional component of autism that may help in the identification of underlying genetic association. Methods:, We conducted factor analyses of RRBI symptoms with a sample that included verbal subjects meeting full criteria for autism aged 5 to 22 years (n = 245). Among affected sibling pairs (n = 126) we examined the familial aggregation of the identified factors. We also examined the associations of the factors with autism-related personality traits in fathers and mothers (n = 50). Results:, The previously identified two-factor model , insistence on sameness (IS) and repetitive stereotypic motor behaviors (RSMB) , was replicated in our sample. Next, a second factor analysis that included the item for verbal rituals resulted in a four-factor model , IS, ,simple' RSMB, ,complex' RSMB, and a fourth factor including symptoms associated with intense preoccupations (IP). Of these four, both IS and IP were significantly familial among affected siblings, but only IP was significantly correlated with the broader autism phenotype traits of rigidity and aloofness in fathers. Conclusions:, The results support previous evidence for the IS factor, its familiality, and the identification of IP as an additional strong candidate trait for genetic studies of autism. [source] | |||||||||||||||||||