Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “sensorimotor behavior”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 433 records · Page 24Linked to original sources
PubMed2004

Induced depressive behavior impairs learning and memory in rats.

While it is generally accepted that cognitive processes such as learning and memory are affected by emotion, the impact of depression on learning and memory has rarely been directly studied in experimental animals. Effects of induced depressive behavior on learning and memory were determined in rats, using an open space swim test, a novel animal model of depressive behavior that is developed recently in our laboratory. The model indexes searching activity of the animals, with the induced depressive immobility behavior showing specific sensitivity to three major prototypic classes of antidepressants and a selective serotonin reuptake inhibitor. The induced depressive behavior in rats showed a delayed response to chronic antidepressant treatment and had a lasting effect on the ability of rats to learn and recall the learned experience. It impaired the subsequent ability of rats to learn and recall both a spatial water maze task and a multi-trial passive avoidance task. These impairments were all sensitive to antidepressant therapeutics, but not to buspirone, an anxiolytic. By way of contrast, the ability of the rats to sense and move to a visible platform and to escape from an unconditioned shock stimulus was neither impaired by inducing the depressive behavior nor altered by the drug treatment, suggesting that non-specific changes in sensorimotor ability were not involved. These impairments of learning and memory indicate that the depressive behavior-induced deficits show generalizability and are not context-limited. This animal model of depressive behavior shows promising potential as a screen for novel antidepressive therapeutics and as a disease model for revealing network/cellular/molecular mechanisms in the pathophysiology of depression and depression-induced cognitive deficits.

Animals↗
PubMed2003

An animal model of generalized nonconvulsive status epilepticus: immediate characteristics and long-term effects.

Absence seizures are traditionally believed to have no significant long-term neurological consequences, but few basic scientific studies have examined the effects of absence seizures on neuronal function, especially regarding absence status epilepticus. We developed a model of generalized nonconvulsive status epilepticus (GNCSE) in rats to study behavioral, functional, and histological effects of GNCSE. Using repetitive timed injections of low-dose pentylenetetrazol (PTZ), a state of prolonged behavioral arrest and immobility associated with frequent generalized spike-wave discharges on EEG could be induced for hours, consistent with GNCSE. GNCSE occurred reproducibly in adult rats, but surprisingly not in juvenile rats or adult mice. There was no evidence of pathological damage following GNCSE using Fluoro-Jade B and Cresyl Violet histological methods. Although a transient, subtle deficit in place learning occurred in PTZ-treated rats, there were no long-term behavioral effects of GNCSE on spatial learning or sensorimotor function. However, 1 week after a single episode of GNCSE, there was an increase in absence seizures in response to a repeat dose of PTZ compared to controls. These results indicate that an animal model of GNCSE can be generated and that even in the absence of overt neuronal damage, GNCSE may produce functional changes in neurons that alter electrical excitability of neural circuits.

Age Factors↗
PubMed2003

Song system auditory responses are stable and highly tuned during sedation, rapidly modulated and unselective during wakefulness, and suppressed by arousal.

We used auditory responsiveness in the avian song system to investigate the complex relationship between behavioral state and sensory processing in a high-order sensorimotor brain area. We present evidence from recordings in awake, anesthetized, and sleeping male zebra finches (Taeniopygia guttata) that auditory responsiveness in nucleus HVc is profoundly affected by changes in behavioral state. In anesthetized and sleeping birds, auditory responses were characterized by an increase in firing rate that was selective for the bird's own song (BOS) and highly stable over time. In contrast, HVc responses during wakefulness were extremely variable and transitioned between undetectable and robust levels over short intervals. Surprisingly, auditory responses in awake birds were not selective for the BOS stimulus. The variability of HVc auditory responses in awake birds suggests that, as in mammals, wakefulness is not a uniform behavioral state. Rather, auditory responsiveness likely is continually influenced by variables such as arousal state. We therefore developed several experimental paradigms in which we could manipulate arousal levels during auditory stimulus presentation. In all cases, arousal suppressed HVc auditory responses. This effect was specific to the song system, as auditory responses in Field L, a primary auditory area that is a source of auditory input to HVc, were unaffected. While arousal acts as a negative regulator of HVc auditory responsiveness, the presence and variability of the responses observed in awake, alert birds suggests that other mechanisms, such as attention, may enhance auditory responsiveness. The interplay between behavioral state and sensory processing may regulate song system responsiveness according to the bird's behavioral and social context.

Acoustic Stimulation↗
PubMed1973

Evidence for higher functions of the cerebellum: eating and grooming elicited by cerebellar stimulation in cats.

Well-organized eating and grooming behaviors were elicited in cats by stimulation of a zone in the cerebellum that extended from the fastigial nucleus to the superior cerebellar peduncle. Behaviors appeared to result from the facilitation of specific sensorimotor mechanisms, rather than the induction of generalized "drive" states. The results emphasize the need for a broad view of cerebellar function.

Animals↗
PubMed2001

Divergent effects of ovarian steroids on neuronal survival during experimental allergic encephalitis in Lewis rats.

Experimental allergic encephalitis, (EAE) a Th1-cell-dependent autoimmune disease of the central nervous system (CNS) used to study immune responses relevant to multiple sclerosis (MS) displays gender susceptibility. The underlying basis of the sexual dimorphism may reflect multiple factors including gender-specific hormones. To study the relationship between ovarian hormones and CNS inflammation, we induced EAE in susceptible female Lewis rats ovariectomized (OVX) 7 days earlier and implanted with blank capsules or capsules containing estradiol (E), progesterone (P), or both (EP). Rats were immunized with complete Freunds' adjuvant alone or combined with guinea pig myelin basic protein. Motor function was scored 0-5 on standard criteria (days 7-11 postimmunization). On day 11, the rats were euthanized and the lumbar spinal cord was analyzed for Nissl, neuron nuclear antigen, and DNA fragmentation with a TUNEL assay. Inflammation was judged qualitatively on a scale of 0-4. Our immunization protocol induced limited sensorimotor deficits in OVX rats (2.3 +/- 0.6, mean +/- SEM) with moderate inflammation (2.5 +/- 0.4). E limited both behavioral impairments (1.0 +/- 0.4) and inflammation (0.5 +/- 0.2). P-treated rats had more severe sensorimotor deficits (3.1 +/- 0.5) with increased inflammatory infiltrates (3.6 +/- 0.4) and markedly increased numbers of TUNEL(+) neurons. Neuron counts of the outer two Rexed lamina (L3-L5) showed a 20% neuron loss (P < 0.02) in P-treated rats with EAE in comparison to other groups. Coadministration of E with P prevented the consequences of P, including neuronal apoptosis (behavioral score, 0.6 +/- 0.6; inflammation, 1.4 +/- 0.5). Our results suggest a potential and novel function of P that increases the vulnerability of neurons to apoptotic injury in EAE and may have pathophysiologic implications in the progression of disability in women with MS.

Animals↗
PubMed2005

Sensorimotor retuning [corrected] in complex regional pain syndrome parallels pain reduction.

Patients with complex regional pain syndrome (CRPS) and intractable pain showed a shrinkage of cortical maps on primary (SI) and secondary somatosensory cortex (SII) contralateral to the affected limb. This was paralleled by an impairment of the two-point discrimination thresholds. Behavioral treatment over 1 to 6 months consisting of graded sensorimotor retuning led to a persistent decrease in pain intensity, which was accompanied by a restoration of the impaired tactile discrimination and regaining of cortical map size in contralateral SI and SII. This suggests that the reversal of tactile impairment and cortical reorganization in CRPS is associated with a decrease in pain.

Behavior Therapy↗
PubMed1999

Characterization of progressive motor deficits in mice transgenic for the human Huntington's disease mutation.

Transgenic mice expressing exon 1 of the human Huntington's disease (HD) gene carrying a 141-157 CAG repeat (line R6/2) develop a progressive neurological phenotype with motor symptoms resembling those seen in HD. We have characterized the motor deficits in R6/2 mice using a battery of behavioral tests selected to measure motor aspects of swimming, fore- and hindlimb coordination, balance, and sensorimotor gating [swimming tank, rotarod, raised beam, fore- and hindpaw footprinting, and acoustic startle/prepulse inhibition (PPI)]. Behavioral testing was performed on female hemizygotic R6/2 transgenic mice (n = 9) and female wild-type littermates (n = 22) between 5 and 14 weeks of age. Transgenic mice did not show an overt behavioral phenotype until around 8 weeks of age. However, as early as 5-6 weeks of age they had significant difficulty swimming, traversing the narrowest square (5 mm) raised beam, and maintaining balance on the rotarod at rotation speeds of 33-44 rpm. Furthermore, they showed significant impairment in prepulse inhibition (an impairment also seen in patients with HD). Between 8 and 15 weeks, R6/2 transgenic mice showed a progressive deterioration in performance on all of the motor tests. Thus R6/2 mice show measurable deficits in motor behavior that begin subtly and increase progressively until death. Our data support the use of R6/2 mice as a model of HD and indicate that they may be useful for evaluating therapeutic strategies for HD, particularly those aimed at reducing the severity of motor symptoms or slowing the course of the disease.

Acoustic Stimulation↗
PubMed2002

Effects of cannabinoid receptor ligands on psychosis-relevant behavior models in the rat.

RATIONALE: Marijuana is known to have psychotropic effects in humans. In this study, we used rat models of sensorimotor gating, hyperactivity and stereotypy to explore whether CB(1) receptor stimulation or blockade induces behavioral changes consistent with psychotomimetic or antipsychotic agents, respectively. OBJECTIVES: We determined whether (a) the cannabinoid agonist CP 55940 decreased pre-pulse inhibition (PPI) as might be expected from a psychotomimetic agent, and (b) the selective CB(1) receptor antagonist, SR 141716A, had any effect on PPI on its own or following disruptions by psychotomimetic agents. In addition, we investigated the effects of SR 141716A on elevated levels of hyperactivity and stereotypy elicited by d-amphetamine. METHODS: These studies were conducted in rats using standard methodologies for determination of PPI following acoustic stimuli, and d-amphetamine-induced hyperactivity and stereotypies. RESULTS: Decreased startle responses to 120 dB stimuli were observed in rats treated with CP 55940 (0.1 mg/kg IP) in the absence and presence of a 73 dB pre-pulse. These effects were reversed by SR 141716A (5 and 10 mg/kg, respectively). SR 141716A (0.1, 5, 10 mg/kg) had no effect on PPI on its own or following disruptions by apomorphine, d-amphetamine or MK-801. Conversely, in separate experiments different antipsychotic agents reversed disruptions in PPI induced by d-amphetamine (haloperidol), apomorphine (haloperidol or clozapine) or MK-801 (clozapine or olanzapine). In addition, unlike haloperidol, SR 141716A (5 mg/kg) did not reverse d-amphetamine-mediated increases in hyperactivity or stereotypy. CONCLUSIONS: The CP 55940-mediated decreases in startle amplitude confound assessment of the effects of CB(1) receptor activation on PPI. The failure of SR 141716A to reverse disruptions in PPI, hyperactivity or stereotypy induced by non-cannabinoid psychotomimetic agents suggests that blockade of the CB(1) receptor on its own is not sufficient for antipsychotic therapy.

Animals↗
PubMed2006

A sensorimotor map: modulating lateral interactions for anticipation and planning.

Experimental studies of reasoning and planned behavior have provided evidence that nervous systems use internal models to perform predictive motor control, imagery, inference, and planning. Classical (model-free) reinforcement learning approaches omit such a model; standard sensorimotor models account for forward and backward functions of sensorimotor dependencies but do not provide a proper neural representation on which to realize planning. We propose a sensorimotor map to represent such an internal model. The map learns a state representation similar to self-organizing maps but is inherently coupled to sensor and motor signals. Motor activations modulate the lateral connection strengths and thereby induce anticipatory shifts of the activity peak on the sensorimotor map. This mechanism encodes a model of the change of stimuli depending on the current motor activities. The activation dynamics on the map are derived from neural field models. An additional dynamic process on the sensorimotor map (derived from dynamic programming) realizes planning and emits corresponding goal-directed motor sequences, for instance, to navigate through a maze.

Action Potentials↗
PubMed1992

Electrocortical arousal and spindles on physiological cortico-subcortical interactions.

The neuronal mechanisms of electrocortical arousal and sleep spindles were reviewed on the basis of intracellular analyses on the motor cortex in atraumatically maintained encéphale isolé cat preparations. When arousal is initiated by subcortical afferents from the brainstem, the cortical neurons respond with either excitation (E), inhibition (I), disfacilitation (DF), or disinhibition (DI), in a cascade pattern proceeding from the superficial to deep layers. These neuronal activities on arousal involve DF of the output neurons that may set the subcortical sensorimotor functions in a readiness state for a possible adaptive behavior of animals. This initial transient arousal termed phasic develops soon to the next, more sustained phase termed tonic by the action of other subcortical afferents. The cascade transmissions then occur again, producing E, I, DF, and DI in the cortical neurons but with a reverse laminar pattern proceeding from the deep to superficial layers. These neuronal activities on tonic and arousal deliver the cortical outputs to the subcortical systems that may trigger an orienting or searching behavior of animals in their environment. Sleep spindles also accompany the cascade transmissions that are partly common to those in arousal. Various modes of the cascade transmissions were further examined by applying electric shock stimuli to the cortical surface, the ventrolateral nucleus of the thalamus, and the cerebral peduncle to activate the subcortical afferents converging onto different cortical layers. The combined results from these experiments may imply that the cortico-subcortical interactions in which all the cortical neurons participate with dynamic harmony are instrumental to set a physiological sequence of animal behavior. If these interactions be impaired on the way of normal growth of the brain, as in the case of disorders with the Rett syndrome, many forms of ill adaptation may be brought about by dedifferentiation of sensorimotor functions.

Action Potentials↗
PubMed2002

Vasopressin V1b receptor knockout reduces aggressive behavior in male mice.

Increased aggression is commonly associated with many neurological and psychiatric disorders. Current treatments are largely empirical and are often accompanied by severe side effects, underscoring the need for a better understanding of the neural bases of aggression. Vasopressin, acting through its 1a receptor subtype, is known to affect aggressive behaviors. The vasopressin 1b receptor (V1bR) is also expressed in the brain, but has received much less attention due to a lack of specific drugs. Here we report that mice without the V1bR exhibit markedly reduced aggression and modestly impaired social recognition. By contrast, they perform normally in all the other behaviors that we have examined, such as sexual behavior, suggesting that reduced aggression and social memory are not simply the result of a global deficit in sensorimotor function or motivation. Fos-mapping within chemosensory responsive regions suggests that the behavioral deficits in V1bR knockout mice are not due to defects in detection and transmission of chemosensory signals to the brain. We suggest that V1bR antagonists could prove useful for treating aggressive behavior seen, for example, in dementias and traumatic brain injuries.

Age Factors↗
PubMedDate not supplied

A neural network model of chemotaxis predicts functions of synaptic connections in the nematode Caenorhabditis elegans.

The anatomical connectivity of the nervous system of the nematode Caenorhabditis elegans has been almost completely described, but determination of the neurophysiological basis of behavior in this system is just beginning. Here we used an optimization algorithm to search for patterns of connectivity sufficient to compute the sensorimotor transformation underlying C. elegans chemotaxis, a simple form of spatial orientation behavior in which turning probability is modulated by the rate of change of chemical concentration. Optimization produced differentiator networks capable of simulating chemotaxis. A surprising feature of these networks was inhibitory feedback connections on all neurons. Further analysis showed that feedback regulates the latency between sensory input and behavior. Common patterns of connectivity between the model and biological networks suggest new functions for previously identified connections in the C. elegans nervous system.

Action Potentials↗
PubMed2006

Behavioral tests for preclinical intervention assessment.

Select functional outcome tests commonly used for evaluating sensorimotor and cognitive capacity in rodents with focal intracerebral ischemic or hemorrhagic injury are described, along with upgrades and issues of concern for translational research. An emphasis is placed on careful quantitative and qualitative assessment of acute and long-term behavioral deficits, and on avoidance of frequent pitfalls. Methods for detecting different degrees of injury and treatment-related improvements are included. Determining the true potential of an intervention requires a set of behavioral analyses that can monitor compensatory learning. In a number of preclinical outcome tests, animals can develop remarkably effective "tricks" that are difficult to detect but frequently lead to dramatic improvements in performance, particularly with repeated practice. However, some interventions may facilitate learning without promoting brain repair, but these may not translate into a meaningful level of benefit in the clinic. Additionally, it is important to determine whether there are any preinjury functional asymmetries in order to accurately assess damage-related changes in behavior. This is illustrated by the fact that some animals have chronic endogenous asymmetries and that others, albeit infrequently, can sustain a spontaneous cerebral stroke, without any experimental induction, that can lead to chronic deficits as reflected by behavioral, imaging, and histological analyses. Finally, a useful new modification of the water maze that involves moving the platform from trial to trial within the target quadrant is reviewed, and its advantages over the standard version are discussed.

Animals↗
PubMed2006

Barhl1 is required for maintenance of a large population of neurons in the zonal layer of the superior colliculus.

The mammalian superior colliculus of the midbrain is a brainstem center that integrates sensorimotor signals involved in the control of orienting behaviors. Its structure is characterized by seven well-organized cellular and fibrous layers associated with distinct physiological properties. To date, however, little is known about the molecular bases governing the lamination, differentiation, and survival of superior collicular neurons. Barhl1 is a homeodomain transcription factor that has been demonstrated to play an essential role in maintaining inner ear hair cells, cerebellar granule cells, and precerebellar neurons. We show here that Barhl1 exhibits a select expression pattern in the superior colliculus with positive neurons largely restricted to the zonal layer, as visualized by the beta-galactosidase activity expressed from the lacZ reporter knocked in the Barhl1 locus. Targeted disruption of Barhl1 results in the loss of a large population of neurons from the zonal layer of the superior colliculus, as indicated by reduced beta-galactosidase staining and marker gene expression as well as by increased apoptotic cell death. Taken together, these data suggest that Barhl1 is crucially required for the survival but not for the specification of zonal layer neurons in the superior colliculus.

Animals↗
PubMed2006

Clinical applicability of functional MRI.

Functional MRI (fMRI) has become the most widely used modality for examining human brain function in basic and clinical neuroscience. As compared to the application of fMRI in basic neuroscience research, clinical fMRI presents unique challenges. A growing body of literature supports the feasibility of clinical fMRI, with the best-studied applications being localization of motor cortex and lateralization of language. While it may be tempting to assume that fMRI will supercede prior approaches, it may turn out that fMRI will be used to complement more difficult or invasive methods rather than replace them entirely. This article focuses on fMRI studies in patients and patient populations. Specific considerations for such applications include pathophysiological effects on functional physiology, brain-behavior correlations in the presence of cognitive or sensorimotor deficits, and test-retest reliability for longitudinal studies.

Brain↗
PubMed2006

N-methyl-D-aspartate receptors in the medial septal area have a role in spatial and emotional learning in the rat.

Cholinergic and GABAergic neurons in the medial septal/vertical limb of the diagonal band of Broca (MS/vDB) area project to the hippocampus and constitute the septohippocampal pathway, which has been implicated in learning and memory. There is also evidence for extrinsic and intrinsic glutamatergic neurons in the MS/vDB, which by regulating septohippocampal neurons can influence hippocampal functions. The potential role of glutamatergic N-methyl-D-aspartate (NMDA) receptors within the MS/vDB for spatial and emotional learning was studied using the water maze and step-through passive avoidance (PA) tasks, which are both hippocampal-dependent. Blockade of septal NMDA receptors by infusion of the competitive NMDA receptor antagonist D-(-)-2-amino-5-phosphonopentanoic acid (D-AP5) (0.3-5 microg/rat), infused 15 min prior to training, impaired spatial learning and memory at the 5 microg dose of D-AP5, while doses of 0.3 and 1 microg per rat had no effect. The impairment in spatial learning appears not to be caused by sensorimotor or motivational disturbances, or anxiogenic-like behavior. Thus, d-AP5-treated rats were not impaired in swim performance or visuospatial abilities and spent more time in the open arms of the elevated plus-maze. In the PA task, intraseptal D-AP5 infused 15 min before training impaired retention as examined 24 h after training. This impairment was observed already at the 0.3 microg dose, suggesting that NMDA receptors within the MS/vDB may be more important for emotional than spatial memory. In summary, the present data indicate that changes in septal glutamate transmission and NMDA receptor activity can influence activity-dependent synaptic plasticity in the hippocampus and thereby learning and memory.

Animals↗
PubMed1998

Assessment of lower urinary tract functional deficit in rats with contusive spinal cord injury.

Traumatic spinal cord injury (SCI) produces lower urinary tract (LUT) dysfunction that has been studied in surgical transection models. Our aim was to assess LUT functional deficit in a clinically relevant model of incomplete SCI to investigate how partial preservation of supraspinal connections might affect LUT dysfunction. Standardized weight-drop contusion (10 g x 2.5 cm) or complete transection, was produced at T8 in female Sprague-Dawley rats. Behavioral tests were used to assess hind limb sensorimotor function at Day 1 after surgery and weekly thereafter. The urometric experiments were conducted on groups (n = 7) of uninjured rats and on injured rats during Weeks 1 and 2 after SCI (before and after spontaneous voiding was established) as well as Week 2 after a complete transection (n = 3). Under anesthesia, the bladder was continuously perfused with saline. Changes in bladder pressure and external urethral sphincter (EUS) electrical activity were monitored. The bladder was then dissected and weighed and both the bladder and spinal cord were fixed for pathoanatomical analyses. Our results indicate that several aspects of LUT dysfunction after contusive SCI were similar to transection, e.g., reduction of voiding efficiency (approximately 5% of normal value), decrease in inter-contraction interval (47%), increase in bladder capacity (8-fold), and weight (4.6-fold). One aspect appeared different from transection--partial recovery from acute bladder/sphincter dyssynergia. Because the coordination of bladder and EUS function is mediated by brainstem pathways, partial recovery of synergy after SCI was likely due to sparing of some relevant bulbospinal projections as was confirmed by retrograde transneuronal viral tracing.

Animals↗
PubMed1998

Differential distribution of amygdaloid input across rostral solitary nucleus subdivisions in rat.

The orosensory nucleus of the solitary tract (NST) receives input from the amygdala, a key node in the forebrain feeding-related network. Despite numerous studies documenting the existence of this pathway, however, too little is known about the input organization to the gustatory brainstem to allow definitive conclusions about its functional role. Therefore, towards the long-term goal of characterizing such descending regulatory pathways, the purpose of the present study was to describe the distribution of input arising from the amygdala. The anterograde tracer, biotinylated dextran, was injected into the central amygdala based on stereotaxic coordinates in seven adult male rats. Following a 2-week survival time, the animals were sacrificed. Transverse sections of the brains were processed to visualize transported tracer and NST anatomical topography. Labeled fibers were differentially distributed among subdivisions throughout the rostrocaudal extent of NST. Within the rostral NST, the medial (M) subdivision had the highest density of terminal-like endings and swellings (30% of total density), followed by the ventral half of rostral central (vRC, 29%), ventral (V, 25%), dorsal half of rostral central (dRC, 12%) and rostral lateral (RL, 4%). In conclusion, it appears that amygdalar input preferentially overlaps with NST subdivisions (M, V, vRC) containing neurons with local efferent projections to the caudal NST and reticular nuclei that are implicated in medullary reflex circuits, rather than with subdivisions (dRC, RL) receiving primary orosensory afferent input and containing neurons having ascending efferent projections to the parabrachial nucleus. Thus, descending feeding-related pathways may be positioned to act as regulatory substrates controlling the output gain of brainstem circuits which may serve to modulate sensorimotor and autonomic reflexes in response to ingestive behaviors.

Amygdala↗