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Complex Cognitive Abilities (complex + cognitive_ability)

Distribution by Scientific Domains

Life Sciences	75%

Selected Abstracts

Late postnatal maturation of excitatory synaptic transmission permits adult-like expression of hippocampal-dependent behaviors

HIPPOCAMPUS, Issue 5 2005
Theodore C. Dumas
Abstract Sensorimotor systems in altricial animals mature incrementally during early postnatal development, with complex cognitive abilities developing late. Of prominence are cognitive processes that depend on an intact hippocampus, such as contextual,configural learning, allocentric and idiocentric navigation, and certain forms of trace conditioning. The mechanisms that regulate the delayed maturation of the hippocampus are not well understood. However, there is support for the idea that these behaviors come "on line" with the final maturation of excitatory synaptic transmission. First, by providing a timeline for the first behavioral expression of various forms of learning and memory, this study illustrates the late maturation of hippocampal-dependent cognitive abilities. Then, functional development of the hippocampus is reviewed to establish the temporal relationship between maturation of excitatory synaptic transmission and the behavioral evidence of adult-like hippocampal processing. These data suggest that, in rats, mechanisms necessary for the expression of adult-like synaptic plasticity become available at around 2 postnatal weeks of age. However, presynaptic plasticity mechanisms, likely necessary for refinement of the hippocampal network, predominate and impede information processing until the third postnatal week. © 2005 Wiley-Liss, Inc. [source]

Intoxication With Bourbon Versus Vodka: Effects on Hangover, Sleep, and Next-Day Neurocognitive Performance in Young Adults

ALCOHOLISM, Issue 3 2010
Damaris J. Rohsenow
Background:, This study assessed the effects of heavy drinking with high or low congener beverages on next-day neurocognitive performance, and the extent to which these effects were mediated by alcohol-related sleep disturbance or alcoholic beverage congeners, and correlated with the intensity of hangover. Methods:, Healthy heavy drinkers age 21 to 33 (n = 95) participated in 2 drinking nights after an acclimatization night. They drank to a mean of 0.11 g% breath alcohol concentration on vodka or bourbon one night with matched placebo the other night, randomized for type and order. Polysomnography recordings were made overnight; self-report and neurocognitive measures were assessed the next morning. Results:, After alcohol, people had more hangover and more decrements in tests requiring both sustained attention and speed. Hangover correlated with poorer performance on these measures. Alcohol decreased sleep efficiency and rapid eye movement sleep, and increased wake time and next-day sleepiness. Alcohol effects on sleep correlated with hangover but did not mediate the effects on performance. No effect of beverage congeners was found except on hangover severity, with people feeling worse after bourbon. Virtually no sex differences appeared. Conclusions:, As drinking to this level affects complex cognitive abilities, safety could be affected, with implications for driving and for safety-sensitive occupations. Congener content affects only how people feel the next day so does not increase risk. The sleep disrupting effects of alcohol did not account for the impaired performance so other mechanisms of effect need to be sought. As hangover symptoms correlate with impaired performance, these might be contributing to the impairment. [source]

A claim in search of evidence: reply to Manger's thermogenesis hypothesis of cetacean brain structure

BIOLOGICAL REVIEWS, Issue 4 2008
Lori Marino
Abstract In a recent publication in Biological Reviews, Manger (2006) made the controversial claim that the large brains of cetaceans evolved to generate heat during oceanic cooling in the Oligocene epoch and not, as is the currently accepted view, as a basis for an increase in cognitive or information-processing capabilities in response to ecological or social pressures. Manger further argued that dolphins and other cetaceans are considerably less intelligent than generally thought. In this review we challenge Manger's arguments and provide abundant evidence that modern cetacean brains are large in order to support complex cognitive abilities driven by social and ecological forces. [source]

Detection of unexpected events during spatial navigation in humans: bottom-up attentional system and neural mechanisms

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 4 2008
Giuseppe Iaria
Abstract Navigation is a complex cognitive ability requiring the processing and integration of several different types of information extracted from the environment. While navigating, however, an unexpected event may suddenly occur, which individuals are required to detect promptly in order to apply an appropriate behavioural response. The alerting mechanism that is integral to the detection of unexpected events is referred to as the bottom-up attentional system. Using event-related functional magnetic resonance imaging, we investigated the neural basis of bottom-up detection of unexpected events while individuals moved within a virtual environment. We identified activation within a right fronto-temporo-parietal network in response to unexpected events while navigating in this virtual environment. Furthermore, when an unexpected event requires an adjusted behavioural response, a region of the right ventrolateral pre-frontal cortex (areas 45 and 47/12) is selectively activated. Our data replicate earlier findings on the neural mechanisms underlying visual attention and extend these findings to the more complex real-life ability of spatial navigation, thereby suggesting that these neural mechanisms subserve the bottom-up attentional systems that are crucial for effective locomotion in real surroundings. [source]