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Goal-directed Behavior (goal-directed + behavior)
Selected AbstractsCholinergic modulation of visuospatial responding in central thalamusEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2007Lori A. Newman Abstract Central thalamus has extensive connections with basal ganglia and frontal cortex that are thought to play a critical role in sensory-guided goal-directed behavior. Central thalamic activity is influenced by cholinergic projections from mesopontine nuclei. To elucidate this function we trained rats to respond to lights in a reaction time (RT) task and compared effects of muscarinic (2.4, 7.3, 22 nmol scopolamine) and nicotinic (5.4, 16, 49, 98 nmol mecamylamine) antagonists with the GABAA agonist muscimol (0.1, 0.3, 1.0 nmol) in central thalamus. We compared this with subcutaneous (systemic) effects of mecamylamine (3.2, 9.7, 29 µmol/kg) and scopolamine (0.03, 0.09, 0.26 µmol/kg). Subcutaneous scopolamine increased omissions (failure to respond within a 3-s response window) at the highest dose tested. Subcutaneous mecamylamine increased omissions at the highest dose tested while impairing RT and per cent correct at lower doses. Intrathalamic injections of muscimol and mecamylamine decreased per cent correct at doses that did not affect omissions or RT. Intrathalamic scopolamine increased omissions and RT at doses that had little effect on per cent correct. Anatomical controls indicated that the effects of mecamylamine were localized in central thalamus and those of scopolamine were not. Drug effects did not interact with attention-demanding manipulations of stimulus duration, proximity of stimulus and response locations, or stimulus array size. These results are consistent with the hypothesis that central thalamus mediates decisional processes linking sensory stimuli with actions, downstream from systems that detect sensory signals. They also provide evidence that this function is specifically influenced by nicotinic cholinergic receptors. [source] Task-dependent changes in frontal brain asymmetry: Effects of incentive cues, outcome expectancies, and motor responsesPSYCHOPHYSIOLOGY, Issue 3 2001Anita Miller The current study was designed to clarify the psychological functions most closely associated with frontal brain asymmetry. Electroencephalography (EEG) was recorded from 60 participants while they performed a delayed reaction time (RT) task that included manipulations of incentive, expectancy, and response. Significant alpha asymmetry effects were reflected in topographic differences across anterior EEG sites. Variations in monetary incentives resulted in parametric changes in anterior frontal alpha asymmetry. Manipulations of outcome expectancies were related to mid-frontal EEG changes that differed for men and women. Varied response requirements were related to central asymmetry patterns. Taken together, the findings suggest that regionally specific patterns of frontal asymmetry are functionally related to particular aspects of approach,withdrawal tendencies involved in the temporal guidance and regulation of goal-directed behavior. [source] Understanding Consciousness Using Systems Approaches and Lexical UniversalsANTHROPOLOGY OF CONSCIOUSNESS, Issue 2 2004Michael Winkelman Ph.D. The numerous perspectives offered on consciousness reflect a multifaceted phenomenon that results from a system of relations. An etymological approach identifies linguistic roots of the meanings of consciousness and illustrates their concern with self-referenced informational relationships of an organism with its environment, a "knowing system" formed in the epistemological relations between knower and known. Common elements of contemporary models suggest that consciousness involves interacting components of a system, including: attention-awareness; phenomenal experiences; self reference; action-behavior, including representations and learning; use of information; interpretation of meaning; goal-directed behavior; and systems of social reference. It is suggested that manifestations of consciousness through the physical properties of the brain are universally represented in language. A preliminary systems model of consciousness is outlined with widespread lexical roots proposed as a culture-neutral framework for constructing theories of consciousness and identifying cognitive constructs which reveal the epistemological roots of consciousness within Indo-European traditions. [source] Voluntariness, intention, and the defence of mental disorder: toward a rational approach,BEHAVIORAL SCIENCES & THE LAW, Issue 5 2003Bernadette McSherry B.A.(Hons), D.Jur., Grad.Dip.Psych., LL.B.(Hons), LL.M. This article addresses how mental disorder may be used in common law countries to negate the requirements of voluntariness and intention in serious criminal offences as well as to provide the basis for current versions of the insanity defence. The notion that mental disorder can cause conduct to become completely involuntary or unintentional is questionable, given current thinking in the behavioral sciences. This article argues that different forms of mental disorder should be subsumed within a separate defence of mental disorder. Providing that a range of dispositional options is available, the law in this complex area would be simplified and brought into line with current psychological notions of goal-directed behavior. Copyright © 2003 John Wiley & Sons, Ltd. [source] Animal Foraging and the Evolution of Goal-Directed CognitionCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 1 2006Thomas T. Hills Abstract Foraging- and feeding-related behaviors across eumetazoans share similar molecular mechanisms, suggesting the early evolution of an optimal foraging behavior called area-restricted search (ARS), involving mechanisms of dopamine and glutamate in the modulation of behavioral focus. Similar mechanisms in the vertebrate basal ganglia control motor behavior and cognition and reveal an evolutionary progression toward increasing internal connections between prefrontal cortex and striatum in moving from amphibian to primate. The basal ganglia in higher vertebrates show the ability to transfer dopaminergic activity from unconditioned stimuli to conditioned stimuli. The evolutionary role of dopamine in the modulation of goal-directed behavior and cognition is further supported by pathologies of human goal-directed cognition, which have motor and cognitive dysfunction and organize themselves, with respect to dopaminergic activity, along the gradient described by ARS, from perseverative to unfocused. The evidence strongly supports the evolution of goal-directed cognition out of mechanisms initially in control of spatial foraging but, through increasing cortical connections, eventually used to forage for information. [source] |