Circaseptan aspects of self-assessed sleep protocols covering 70 nights on 33 clinically healthy persons

This study aimed to describe quantitatively some changes in sleep behavior. During 70 consecutive nights, 28 women and 3 men, 30 to 40 years of age and presumably clinically healthy, recorded the time of each awakening. Time of falling asleep were estimated from markings at 10-min. intervals from the times of lying down to sleep as an indication that the subject had not yet fallen asleep. Sleep duration and an index of effective sleep derived therefrom were analyzed by rhythmometric methods. On a group basis, anticipated components with periods of 1 and 0.5 wk., synchronized with the social schedule, were detected with statistical significance. Until long-term polysomnographic monitoring can readily cover the week automatically rather than only one or a few daily sleep spans, the self-monitoring of sleep behavior, yielding the circaseptan endpoints derived herein, may serve as a cost-effective tool in sleep research. By virtue of their relative simplicity, they could be part of a protocol designed to assess pharmacologic or nonpharmacologic interventions of sleep disturbance aimed at restoring undisturbed sleep.     

Unconscious consciousness in Husserl and Freud

A clarification of Husserl's changing conceptions of imaginary consciousness (phantasy) and memory, especially at the level of auto-affective time-consciousness, suggests an interpretation of Freud's concept of the Unconscious. Phenomenology of consciousness can show how it is possible that consciousness can bring to present appearance something unconscious, that is, something foreign or absent to consciousness, without incorporating it into or subordinating it to the conscious present. This phenomenological analysis of Freud's concept of the Unconscious leads to a partial critique of Freud's metapsychological determination of the Unconscious as a simple, internally unperceived representational consciousness. It also suggests an account of how a reproductive inner consciousness can free the subject from the experience of anxiety by allowing for possibilities of self-distanciation and symbolic self-representation that protect the subject from traumatic affection by and through its own instinctual drives.     

Spatial conceptual influences on the coordination of bimanual actions: when a dual task becomes a single task

When the left and right hands produce 2 different rhythms simultaneously, coordination of the hands is difficult unless the rhythms can be integrated into a unified temporal pattern. In the present study, the authors investigated whether a similar account can be applied to the spatial domain. Participants (N = 8) produced a movement trajectory of semicircular form in single-limb and bimanual conditions. In the bimanual tasks, 1 limb moved above the other in the frontal plane. Bimanual unified tasks were constructed so that the spatial paths to be produced by the 2 limbs could be easily conceptualized as parts of a unified circle pattern. Bimanual distinct tasks availed a less obvious spatial pattern that would unify the 2 tasks, despite similar demands placed on the coordination dynamics in the 2 cases (e.g., the phase relations). The authors conclude that a dual task becomes a single task, and interlimb interference is reduced, when the spatial patterns produced by the 2 hands form a geometric arrangement that can be conceptualized as a unified representation.     

Withdrawal from cocaine self-administration produces long-lasting deficits in orbitofrontal-dependent reversal learning in rats

Drug addicts make poor decisions. These decision-making deficits have been modeled in addicts and laboratory animals using reversal-learning tasks. However, persistent reversal-learning impairments have been shown in rats and monkeys only after noncontingent cocaine injections. Current thinking holds that to represent the human condition effectively, animal models of addiction must utilize self-administration procedures in which drug is earned contingently; thus, it remains unclear whether reversal-learning deficits caused by noncontingent cocaine exposure are relevant to addiction. To test whether reversal learning deficits are caused by contingent cocaine exposure, we trained rats to self-administer cocaine, assessed cue-induced cocaine seeking in extinction tests after 1 and 30 d of withdrawal, and then tested for reversal learning more than a month later. We found robust time-dependent increases in cue-induced cocaine seeking in the two extinction tests (incubation of craving) and severe reversal-learning impairments.     

Experience-dependent effects in unimanual and bimanual reaction time tasks in musicians

Engaging in musical training has been shown to result in long-term cognitive benefits. The authors examined whether basic cognitive-motor processes differ in people with extensive musical training and in nonmusicians. Musicians (n = 20) and nonmusicians (n = 20) performed a simple reaction time (RT) task under unimanual and bimanual conditions. Musicians' RTs were faster overall than were those of nonmusicians, and those who began their musical training at an earlier age (around age 7-8 years, on average) exhibited a larger bimanual cost than did those who began later (around 12 years, on average). The authors conclude that experience-dependent changes associated with musical training can result in greater efficacy of interhemispheric connections if those changes occur during certain critical periods of brain development.