Search results for "habitu"
showing 10 items of 179 documents
New determinants of olfactory habituation
2017
AbstractHabituation is a filter that optimizes the processing of information by our brain in all sensory modalities. It results in an unconscious reduced responsiveness to continuous or repetitive stimulation. In olfaction, the main question is whether habituation works the same way for any odorant or whether we habituate differently to each odorant? In particular, whether chemical, physical or perceptual cues can limit or increase habituation. To test this, the odour intensity of 32 odorants differing in physicochemical characteristics was rated by 58 participants continuously during 120s. Each odorant was delivered at a constant concentration. Results showed odorants differed significantl…
Influence of massed and distributed context preexposure on contextual fear and Egr-1 expression in the basolateral amygdala
2007
Preexposure to the conditioning context can influence the expression of context-conditioned fear. We used behavioral and early growth response gene (egr-1) assays in rats to study the effects of massed and distributed context preexposure on context-conditioned fear. The results demonstrated that massed context preexposure impaired acquisition of contextual fear, an effect here referred to as delayed shock deficit. Spaced context preexposure produced similar inhibitory effects. Significantly, the introduction of a brief change of context prior to conditioning completely reversed the deficit induced by massed, but not by distributed, context preexposure. This reversibility was inversely relat…
Electrolytic lesion of the nucleus incertus retards extinction of auditory conditioned fear
2013
Fear memory circuits in the brain function to allow animals and humans to recognize putative sources of danger and adopt an appropriate behavioral response; and research on animal models of fear have helped reveal the anatomical and neurochemical nature of these circuits. The nucleus (n.) incertus in the dorsal pontine tegmentum provides a strong GABAergic projection to forebrain ‘fear centers’ and is strongly activated by neurogenic stressors. In this study in adult male rats, we examined the effect of electrolytic lesions of n. incertus on different stages of the fear conditioning-extinction process and correlated the outcomes with anatomical data on the distribution of n. incertus-derive…
What Makes a 97-Year-Old Man Cycle 5,000 km a Year?
2016
<b><i>Background:</i></b> The nature versus nurture debate is one of the oldest issues in the study of longevity, health and successful aging. <b><i>Objective:</i></b> We present a 97-year-old man (I.K.) as an example of the effects of habitual exercise on the aging process. <b><i>Methods:</i></b> Extensive assessments included medical examinations, interviews, musculoskeletal structure, performance characteristics, cognitive function and gut microbiota composition. <b><i>Results:</i></b> I.K. suffers from iatrogenic hypogonadism, prostate cancer, hypothyroidism and a history of deep popliteal th…
Does Observation of Postural Imbalance Induce a Postural Reaction?
2011
Import JabRef | WosArea Life Sciences and Biomedicine - Other Topics; International audience; Background: Several studies bring evidence that action observation elicits contagious responses during social interactions. However automatic imitative tendencies are generally inhibited and it remains unclear in which conditions mere action observation triggers motor behaviours. In this study, we addressed the question of contagious postural responses when observing human imbalance. Methodology/Principal Findings: We recorded participants' body sway while they observed a fixation cross (control condition), an upright point-light display of a gymnast balancing on a rope, and the same point-light di…
Intraspecific Communication Through Chemical Signals in Female Mice: Reinforcing Properties of Involatile Male Sexual Pheromones
2006
In rodents, social and reproductive behaviors critically depend on chemical signals, including sexual pheromones that have been suggested (but not demonstrated) to be rewarding. In this work, we analyze this issue by studying the chemoinvestigatory behavior of adult female mice (without experience with male-derived chemicals) toward 1) the synthetic odorant citralva, 2) bedding soiled by different conspecifics (females, males, and castrated males), and 3) volatiles derived from bedding soiled by males and castrated males (confronted in 2-choice tests). We also study whether these chemical signals are able to induce conditioned place preference, a reliable test for rewarding properties of st…
Behavioural and biochemical stress responses of Palinurus elephas after exposure to boat noise pollution in tank
2014
This study examined the effects of boat noise on the behavioural and biochemical parameters of the Mediterranean spiny lobster (Palinurus elephas).The experiment was conducted in a tank equipped with a video and audio recording system. 18 experimental trials, assigned to boat noise and control conditions, were performed using lobsters in single and group of 4 specimens. After a 1. h habituation period, we audio- and video-recorded the lobsters for 1. h. During the experimental phase, the animals assigned to the boat groups were exposed to boat noise pollution (a random sequence of boat noises). Exposure to the noise produced significant variations in locomotor behaviours and haemolymphatic …
Parental education associations with children's body composition: Mediation effects of energy balance-related behaviors within the ENERGY-project
2013
AbstractBackgroundIt is well known that the prevalence of overweight and obesity is considerably higher among youth from lower socio-economic families, but there is little information about the role of some energy balance-related behaviors in the association between socio-economic status and childhood overweight and obesity. The objective of this paper was to assess the possible mediation role of energy balance-related behaviors in the association between parental education and children’s body composition.MethodsData were obtained from the cross sectional study of the “EuropeaN Energy balance Research to prevent excessive weight Gain among Youth” (ENERGY) project. 2121 boys and 2516 girls a…
Learning to Eat Vegetables in Early Life: The Role of Timing, Age and Individual Eating Traits
2014
Vegetable intake is generally low among children, who appear to be especially fussy during the pre-school years. Repeated exposure is known to enhance intake of a novel vegetable in early life but individual differences in response to familiarisation have emerged from recent studies. In order to understand the factors which predict different responses to repeated exposure, data from the same experiment conducted in three groups of children from three countries (n = 332) aged 4-38 m (18.9 +/- 9.9 m) were combined and modelled. During the intervention period each child was given between 5 and 10 exposures to a novel vegetable (artichoke puree) in one of three versions (basic, sweet or added e…
Long-term habituation to spatial novelty in blind cave fish (Astyanax hubbsi): role of the telencephalon and its subregions.
2000
Blind cave fish, when released into a novel environment, show a typical exploratory behavior characterized by high swim speed along walls shortly after release. This behavior wanes during prolonged exposure and thus may reflect habituation to novelty. As the hippocampus of mammals, which plays a crucial role in spatial learning, is part of the telencephalon, the possible involvement of this brain structure of fish was investigated in exploratory behavior. Ablation of the whole telencephalon or bilateral removal of dorsal parts of the hemispheres reduced activity; in contrast, unilateral lesions of one hemisphere, bilateral lesions of dorsal and dorsoventral parts, and removal of olfactory b…