Behavioral neuroscience
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Behavioral neuroscience · Dec 2011
Risky business: executive function, personality, and reckless behavior during adolescence and emerging adulthood.
Adolescence is a risky business. Despite outstanding physical health, the risk of injury or death during adolescence is 2-3 times that of childhood. The primary cause of this increase in morbidity and mortality is heightened risky behavior including drinking, driving, drug-taking, smoking, and unprotected sex. ⋯ The community sample of 136 adolescents aged 13- to 17-years-old and 57 emerging adults aged 18- to 22-years-old exhibited marked individual differences in risk-taking behavior; participants' scores on a alcohol, smoking, drugs, sex, driving, and antisocial behavior questionnaire ranged from 0 to near the maximum value possible. We found that risky personality and performance on the neuropsychological tests were both significant predictors of real-world risk-taking. These data have important implications for current public policies involving adolescents and emerging adults.
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Behavioral neuroscience · Dec 2011
Comparative StudyEffects of chronic intermittent ethanol exposure on orbitofrontal and medial prefrontal cortex-dependent behaviors in mice.
In humans, stroke or trauma-induced damage to the orbitofrontal cortex (OFC) or medial prefrontal cortex (mPFC) results in impaired cognitive flexibility. Alcoholics also exhibit similar deficits in cognitive flexibility, suggesting that the OFC and mPFC are susceptible to alcohol-induced dysfunction. The present experiments investigated this issue using an attention set-shifting assay in ethanol dependent adult male C57BL/6J mice. ⋯ Unexpectedly, performance on the set-shifting task was not impaired during abstinence from ethanol. These data suggest reversal learning, but not attention set-shifting, is transiently disrupted during short-term abstinence from CIE. Given that reversal learning requires an intact OFC, these findings support the idea that the OFC may be vulnerable to the cognitive impairing actions of ethanol.
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Behavioral neuroscience · Dec 2011
Impairment of recovery from incentive downshift after lesions of the anterior cingulate cortex: emotional or cognitive deficits?
The anterior cinculate cortex (ACC) is known to be implicated in pain-fear and reward expectations. Animals were given electrolytic lesions of the ACC and then trained in the consummatory successive negative contrast (cSNC) situation. In cSNC, animals exposed to an incentive downshift from 32% to 4% sucrose exhibit less consummatory behavior than animals always exposed to 4% sucrose. ⋯ However, ACC animals exhibited a significant retardation of recovery from cSNC relative to downshifted shams. Within-trial analysis of consummatory behavior indicated that ACC lesions facilitated cSNC during both the initial and last 100 s of postshift trials after the first downshift experience, relative to sham controls. These results suggest that the ACC is part of the neural circuit normally involved in coping with the emotional response induced by the incentive downshift event by inducing learning of the new incentive conditions.
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Behavioral neuroscience · Oct 2011
Comparative StudyReactivation, interference, and reconsolidation: are recent and remote memories likewise susceptible?
The retrieval of a consolidated, apparently stable memory can return it to a labile state, necessitating another period of stabilization, termed reconsolidation. During reconsolidation, memories are susceptible to modifications, thus providing the opportunity to change unwanted memories. In a test of whether the possibility to alter retrieved memories depends on the age of the memories, participants learned a set of emotional and neutral pictures and recalled it 1, 7, or 28 days later. ⋯ Learning new pictures interfered with 1-day-old and 28-day-old memories but not with 7-day-old memories. Evidence for reconsolidation effects was generally rather weak and at most present for 7-day-old memories. These findings show that retrieval and interference have opposite effects on memory that depend on the remoteness of the memories and raise the question under which conditions reconsolidation effects occur in human memory.
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Behavioral neuroscience · Aug 2011
Spontaneous recovery but not reinstatement of the extinguished conditioned eyeblink response in the rat.
Reinstatement--the return of an extinguished conditioned response (CR) after reexposure to the unconditioned stimulus (US)--and spontaneous recovery--the return of an extinguished CR with the passage of time--are 2 of 4 well-established phenomena that demonstrate that extinction does not erase the conditioned stimulus (CS)-US association. However, reinstatement of extinguished eyeblink CRs has never been demonstrated, and spontaneous recovery of extinguished eyeblink CRs has not been systematically demonstrated in rodent eyeblink conditioning. In Experiment 1, US reexposure was administered 24 hr prior to a reinstatement test. ⋯ There was no reinstatement observed in any experiment. With stimulus conditions that produce eyeblink conditioning and research designs that produce reinstatement in other forms of classical conditioning, we observed spontaneous recovery but not reinstatement of extinguished eyeblink CRs. This suggests that reinstatement, but not spontaneous recovery, is a preparation- or substrate-dependent phenomenon.