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Behavioral Sensitivity (behavioral + sensitivity)
Selected AbstractsTranssexual limb transplants in fiddler crabs and expression of novel sensory capabilitiesTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 4 2001Marc J. Weissburg Abstract We used transsexual limb transplants in fiddler crabs to examine how peripheral sensory structures interact with the central nervous system (CNS) to produce a sexually dimorphic behavior. Female and male chemosensory feeding claws were transplanted onto male hosts in place of nonfeeding, nonchemosensory claws. Successfully transplanted claws retain donor morphologies and contain chemosensory neurons. Neurons in successfully transplanted female feeding claws express the enhanced sensitivity to chemical cues seen in female, but not male, neurons in claws of normal animals. When chemically stimulated, the transplanted claws evoke feeding behavior not observed in normal males, even though the sensory neurons in the transplanted limb project to the host's sexually dimorphic neuropil not known to receive chemosensory input. Behavioral sensitivity is directly related to the sensitivity of peripheral neurons in the transplanted feeding claw. Thus, the interactions between peripheral neurons and their targets may restructure the CNS so that novel sensory capabilities are expressed, and this can produce sexually dimorphic behaviors. J. Comp. Neurol. 440:311,320, 2001. © 2001 Wiley-Liss, Inc. [source] REVIEW: Acute withdrawal, protracted abstinence and negative affect in alcoholism: are they linked?ADDICTION BIOLOGY, Issue 2 2010Markus Heilig ABSTRACT The role of withdrawal-related phenomena in the development and maintenance of alcohol addiction remains under debate. A ,self-medication' framework postulates that emotional changes are induced by a history of alcohol use, persist into abstinence, and are a major factor in maintaining alcoholism. This view initially focused on negative emotional states during early withdrawal: these are pronounced, occur in the vast majority of alcohol-dependent patients, and are characterized by depressed mood and elevated anxiety. This concept lost popularity with the realization that in most patients, these symptoms abate over 3,6 weeks of abstinence, while relapse risk persists long beyond this period. More recently, animal data have established that a prolonged history of alcohol dependence induces more subtle neuroadaptations. These confer altered emotional processing that persists long into protracted abstinence. The resulting behavioral phenotype is characterized by excessive voluntary alcohol intake and increased behavioral sensitivity to stress. Emerging human data support the clinical relevance of negative emotionality for protracted abstinence and relapse. These developments prompt a series of research questions: (1) are processes observed during acute withdrawal, while transient in nature, mechanistically related to those that remain during protracted abstinence?; (2) is susceptibility to negative emotionality in acute withdrawal in part due to heritable factors, similar to what animal models have indicated for susceptibility to physical aspects of withdrawal?; and (3) to what extent is susceptibility to negative affect that persists into protracted abstinence heritable? [source] Effect of a dose of ethanol on acute tolerance and ethanol consumption in alcohol drinker(UChB) and non-drinker (UChA) ratsADDICTION BIOLOGY, Issue 3 2002Lutske Tampier Acute tolerance that develops within minutes of ethanol exposure appears to influence the apparent acute behavioral sensitivity of laboratory animals to ethanol actions. The existence of a correlation between voluntary ethanol consumption and the speed of acquiring acute tolerance has been proposed. In the present paper we investigated the effect of an acute dose of ethanol on tolerance development and on ethanol voluntary consumption in our two selected bred strains, UChA (low ethanol drinker) and UChB (high ethanol drinker) rats. Acute tolerance developed to motor impairment induced by a dose of ethanol of 2.3 g/kg. administered intraperitoneally was evaluated by the tilting plane test. Voluntary ethanol consumption was compared in rats receiving the ethanol dose, to rats receiving a saline intraperitoneal (i.p.) injection. The results show that UChB rats receiving an intoxicating dose of ethanol develop more tolerance and they significantly increased their ethanol consumption compared to the same line that received a saline injection, while no change in acute tolerance and voluntary ethanol consumption were obtained in UChA rats. In conclusion, a possible mechanism by which UChB rats drink high amounts of ethanol appears to be the development of tolerance to the pharmacological effects of ethanol. [source] Reflection in thought and action: Maternal parenting reflectivity predicts mind-minded comments and interactive behaviorINFANT MENTAL HEALTH JOURNAL, Issue 4 2008Katherine L. Rosenblum Recent research has identified mothers' mental reflective functioning and verbal mind-minded comments as important predictors of subsequent infant attachment security. In the present study, we examine associations between mothers' (N = 95) parenting reflectivity expressed in an interview and observed parenting behavior, including verbal mind-minded comments and interactive behavior during interaction with their 7-month-old infants. Parenting reflectivity was coded from the Working Model of the Child Interview. Maternal behavior was assessed via observations of mother,infant interaction during free play and structured teaching tasks. Both maternal appropriate mind-minded comments as well as other indicators of maternal interactive behavior were coded. Parenting reflectivity was positively correlated with mind-minded comments and behavioral sensitivity. Hierarchical multiple regression analyses indicated that parenting reflectivity contributed to maternal behavior beyond the contributions of mothers' educational status and depression symptoms. Discussion emphasizes the importance of individual differences in parental capacity to accurately perceive and mentalize their infants' experience, and the consequences of these differences for caregiving behavior. [source] Exercise Neuroprotection in a Rat Model of Binge Alcohol ConsumptionALCOHOLISM, Issue 3 2010J. Leigh Leasure Background:, Excessive alcohol intake produces structural and functional deficits in corticolimbic pathways that are thought to underlie cognitive deficits in the alcohol use disorders (AUDs). Animal models of binge alcohol administration support the direct link of high levels of alcohol consumption and neurotoxicity in the hippocampus and surrounding cortex. In contrast, voluntary wheel running enhances hippocampal neurogenesis and generally promotes the health of neurons. Methods:, We investigated whether voluntary exercise prior to binge alcohol exposure could protect against alcohol-induced cell loss. Female Long-Evans rats exercised voluntarily for 14 days before undergoing 4 days of binge alcohol consumption. Brains were harvested immediately after the last dose of alcohol and examined for various histological markers of neurodegeneration, including both cell death (FluoroJade B) and cell birth (Ki67) markers. Results:, Rats that exercised prior to binge exposure were significantly less behaviorally intoxicated, which was not a result of enhanced hepatic metabolism. Rats that exercised prior to binge alcohol consumption had reduced loss of dentate gyrus granule cells and fewer FluoroJade B positive cells in the dentate gyrus and associated entorhinal-perirhinal cortex compared to nonexercisers. However, exercise did not protect against cell death in the piriform cortex nor protect against alcohol-induced decreases in cell proliferation, evidenced by a similar alcohol-induced reduction in Ki67 labeled cells between exercise and sedentary rats. Conclusions:, We conclude that exercise can reduce behavioral sensitivity to ethanol intoxication and protect vulnerable brain areas from alcohol-induced cell death. Exercise neuroprotection of alcohol-induced brain damage has important implications in understanding the neurobiology of the AUDs as well as in developing novel treatment strategies. [source] Incentive-elicited mesolimbic activation and externalizing symptomatology in adolescentsTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 7 2010James M. Bjork Background:, Opponent-process theories of externalizing disorders (ExD) attribute them to some combination of overactive reward processing systems and/or underactive behavior inhibition systems. Reward processing has been indexed by recruitment of incentive-motivational neurocircuitry of the ventral striatum (VS), including nucleus accumbens (NAcc). Methods:, We used functional magnetic resonance imaging (fMRI) with an incentive task to determine whether externalizing symptomatology in adolescence is correlated with an enhanced VS recruitment by cues for rewards, or by deliveries of rewards. Twelve community-recruited adolescents with externalizing disorders (AED) and 12 age/gender-matched controls responded to targets to win or avoid losing $0, $0.20, $1, $5, or an unknown amount (ranging from $0.20 to $5). Results:, Cues to respond for rewards activated the NAcc (relative to cues for no incentive), in both subject groups similarly, with greatest NAcc recruitment by cues for the largest reward. Loss-anticipatory NAcc signal increase was detected in a volume-of-interest analysis , but this increase occurred only in trials when subjects hit the target. Relative to controls, AED showed significantly elevated NAcc activation by a linear contrast between reward notification versus notification of failure to win reward. In a post hoc reanalysis, VS and pregenual anterior cingulate activation by the reward versus non-reward outcome contrast also directly correlated with Child Behavior Checklist (CBCL) Externalizing total scores (across all subjects) in lieu of a binary diagnosis. Finally, both groups showed right insula activation by loss notifications (contrasted with avoided losses). Conclusions:, Externalizing behavior, whether assessed dimensionally with a questionnaire, or in the form of a diagnostic categorization, is associated with an exaggerated limbic response to outcomes of reward-directed behavior. This could be a neurobiological signature of the behavioral sensitivity to laboratory reward delivery that is characteristic of children with externalizing symptomatology. Of interest is future research on incentive-motivational processing in more severe, clinically referred AED. [source] | ||||||||||