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Motor Reactivity (motor + reactivity)

Distribution by Scientific Domains

Medical Sciences	50%

Selected Abstracts

Prenatal predictors of infant temperament

DEVELOPMENTAL PSYCHOBIOLOGY, Issue 5 2007
Elizabeth A. Werner
Abstract Emerging data suggest that prenatal factors influence children's temperament. In 50 dyads, we examined fetal heart rate (FHR) activity and women's antenatal psychiatric illness as predictors of infant temperament at 4 months (response to novelty and the Infant Behavior Checklist). FHR change during maternal challenge was positively associated with observed infant motor reactivity to novelty (p,=,.02). The odds of being classified as high versus low motor among fetuses who had an increase in FHR during maternal stress was 11 times those who had a decrease in FHR (p,=,.0006). Antenatal psychiatric diagnosis was associated with an almost fourfold greater odds of having a high cry reactivity classification (p,=,.03). There also were modest associations between baseline FHR and maternal reports of infant temperament and between observed temperament and that based on mothers' reports. All of the infant results were found independent of the influence of women's postnatal anxiety. These data indicate that physiological markers of individual differences in infant temperament are identifiable in the fetal period, and possibly shaped by the prenatal environment. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 474-484, 2007. [source]

Gamma activity and reactivity in human thalamic local field potentials

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2009
Florian Kempf
Abstract Depth recordings in patients with Parkinson's disease on dopaminergic therapy have revealed a tendency for oscillatory activity in the basal ganglia that is sharply tuned to frequencies of ,70 Hz and increases with voluntary movement. It is unclear whether this activity is essentially physiological and whether it might be involved in arousal processes. Here we demonstrate an oscillatory activity with similar spectral characteristics and motor reactivity in the human thalamus. Depth signals were recorded in 29 patients in whom the ventral intermediate or centromedian nucleus were surgically targeted for deep brain stimulation. Thirteen patients with four different pathologies showed sharply tuned activity centred at ,70 Hz in spectra of thalamic local field potential (LFP) recordings. This activity was modulated by movement and, critically, varied over the sleep,wake cycle, being suppressed during slow wave sleep and re-emergent during rapid eye movement sleep, which physiologically bears strong similarities with the waking state. It was enhanced by startle-eliciting stimuli, also consistent with modulation by arousal state. The link between this pattern of thalamic activity and that of similar frequency in the basal ganglia was strengthened by the finding that fast thalamic oscillations were lost in untreated parkinsonian patients, paralleling the behaviour of this activity in the basal ganglia. Furthermore, there was sharply tuned coherence between thalamic and pallidal LFP activity at ,70 Hz in eight out of the 11 patients in whom globus pallidus and thalamus were simultaneously implanted. Subcortical oscillatory activity at ,70 Hz may be involved in movement and arousal. [source]

Fetal Learning With Ethanol: Correlations Between Maternal Hypothermia During Pregnancy and Neonatal Responsiveness to Chemosensory Cues of the Drug

ALCOHOLISM, Issue 5 2004
Paula Abate
Abstract: Background: Fetuses learn about ethanol odor when the drug is present in the amniotic fluid. Prenatal learning comprising ethanol's chemosensory cues also suggests an acquired association between ethanol's chemosensory and postabsorptive properties. Ethanol-related thermal disruptions have been implicated as a significant component of the drug's unconditioned properties. In the present study, ethanol-induced thermal changes were analyzed in pregnant rats subjected to a moderate ethanol dose. This thermal response was later tested for its correlation with the responsiveness of the progeny to ethanol and nonethanol chemosensory stimuli. Methods: During gestational day (GD) 14, pregnant rats were subjected to a minor surgical procedure to place a subcutaneous telemetric thermal sensor in the nape of the neck. During GDs 17 to 20, females received a daily intragastric administration of ethanol (2 g/kg) or water, using solutions kept at room temperature. Maternal body temperatures were recorded before and after (4 consecutive hours) the administration of water or ethanol. Newborns representative of both prenatal treatments were tested in terms of behavioral activity elicited by the smell of ethanol or of a novel odorant (cineole). A third group of pups were tested in response to unscented air stimulation. Results: Ethanol administration during late gestation induced reliable maternal hypothermia, a thermal disruption greater than that observed in water-treated females. It was systematically observed that maternal ethanol-induced hypothermia negatively correlated with neonatal motor reactivity elicited by ethanol olfactory stimulation. No other significant correlations were observed in terms of responsiveness to cineole or to unscented air in animals prenatally exposed to ethanol or water. Conclusions: In conjunction with prior research, the present results indicate that fetal ethanol exposure may yield learning of an association between ethanol's sensory and unconditioned properties. Ethanol-induced hypothermia during late gestation seems to represent a significant component of ethanol's unconditioned consequences. Specifically, ethanol-related thermal disruptions in the womb are highly predictive of neonatal responsiveness to ethanol's chemosensory cues that are known to be processed by the near-term fetus. [source]

Alterations of intestinal motor responses to various stimuli after Nippostrongylus brasiliensis infection in rats: role of mast cells

NEUROGASTROENTEROLOGY & MOTILITY, Issue 3 2000
J. Gay
Nippostrongylus brasiliensis infection induces jejunal mastocytosis associated with enteric nerve remodelling in rats. The aim of this study was to evaluate the intestinal motility responses to meals and to neurotransmitters involved in the control of gut motility (acetylcholine (carbachol), substance P and neurokinin A) in both control and N. brasiliensis -infected rats 30 days post-infection. All rats were equipped with NiCr electrodes in the jejunum to record myoelectrical activity. The duration of disruption of the jejunal migrating myoelectrical complexes (MMC) induced by the different stimuli was determined. Meal ingestion and substance P administration disrupted the MMC pattern for similar durations in the two groups. Carbachol and neurokinin A induced a significantly longer MMC disruption in post-infected rats than in controls (125 ± 8.3 vs. 70 ± 6 min for carbachol 100 ,g kg,1 and 51 ± 4 vs. 40 ± 2 for neurokinin A 50 ,g kg,1). The enhanced motor response in postinfected rats was reduced by previous mast cell stabilization with ketotifen or mast cell degranulation with compound BrX 537 A. In conclusion, the increased intestinal motor reactivity to carbachol and neurokinin A in post- N. brasiliensis -infected rats depends upon intestinal mast cell hyperplasia and degranulation. [source]