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Factor analyses of 75 facet scales from 2 major Big Five inventories, in the Eugene-Springfield community sample (N=481), produced a 2-factor solution for the 15 facets in each domain. These findings indicate the existence of 2 distinct (but correlated) aspects within each of the Big Five, representing an intermediate level of personality structure between(More)
We characterize Openness/Intellect as motivated cognitive flexibility, or cognitive exploration, and develop a neuropsychological model relating it to dopaminergic function and to the functions of the prefrontal cortex (PFC). Evidence is reviewed for sources of Openness/Intellect shared with Extraversion and sources unique to Openness/Intellect. The(More)
Individuals use and misuse alcohol (and other drugs) because of the pharmacologically mediated effects these substances have on the operation of 4 psychobiological systems, mediating response to motivationally relevant unconditioned and conditioned stimuli. These 4 systems have unique neuroanatomical structure, biochemical modes of operation, association(More)
In a university sample (n=245) and a community sample (n=222), we replicate the higher-order factor solution for the Five Factor Model (Big Five) reported by Digman (Digman, J. M. (1997). Higher-order factors of the Big Five. We present a biologically predicated model of these two personality factors, relating them to serotonergic and dopaminergic function,(More)
Reductions in latent inhibition (LI), the capacity to screen from conscious awareness stimuli previously experienced as irrelevant, have been generally associated with the tendency towards psychosis. However, "failure" to screen out previously irrelevant stimuli might also hypothetically contribute to original thinking, particularly in combination with high(More)
Entropy, a concept derived from thermodynamics and information theory, describes the amount of uncertainty and disorder within a system. Self-organizing systems engage in a continual dialogue with the environment and must adapt themselves to changing circumstances to keep internal entropy at a manageable level. We propose the entropy model of uncertainty(More)
Latent inhibition (LI) is a preconscious gating mechanism that allows animals with complex nervous systems to ignore stimuli previously experienced as irrelevant. Decreased LI has been associated with dopaminergic agonist intoxication and schizophrenic conditions. We previously demonstrated reductions in LI among individuals characterized by higher levels(More)
Although initially believed to contain orthogonal dimensions, the Big Five personality taxonomy appears to have a replicable higher-order structure, with the metatrait of Plasticity reflecting the shared variance between Extraversion and Openness/Intellect, and the metatrait of Stability reflecting the shared variance among Neuroticism, Agreeableness, and(More)
Acute alcohol intoxication produces changes in the cognitive functioning of normal individuals. These changes appear similar prima facie to those exhibited by individuals who sustain prefrontal lobe damage during adulthood. In order to test the validity of this observation, and to control for the confounding effects of expectancy, 72 male subjects were(More)
BACKGROUND Dopaminergic neurotransmission is implicated in externalizing behavior problems, such as aggression and hyperactivity. Externalizing behavior is known to be negatively associated with cognitive ability. Activation of dopamine D4 receptors appears to inhibit the functioning of the prefrontal cortex, a brain region implicated in cognitive ability.(More)