Circadian factors during sustained performance: Background and methodology

Cornell University Medical College, Westchester Division, The New York Hospital, White Plains, New York It is well established that there is a complex timekeeping mechanism in the human brain. This mechanism is associated with a variety of physiological and psychological rhythms having a period of about a day, and thus referred to as circadian rhythms. The circadian system has recently been modeled in terms of two underlying oscillators, one much more resistant to changes in routine than the other. These oscillators are considered to be endogenous, that is, internal to the organism, and not reliant for their existence upon changes in the person’s environment or general behavior. They thus continue to run even when the sleep/wake cycle is suspended, as in sustained operations. Thus, by their very nature, sustained operations require the individual to override the inputs that are coming from his or her circadian system (especially the indication that sleep is required). The aim of this paper is to provide a background to the area of circadian rhythms research, including a section on the methodology, so that the impact of the circadian system on sustained operations can be better understood.     

Geometric and semantic similarity in visual masking

Semantic and geometric or physical similarity were manipulated separately in a backward-masking situation. When the target was a word to be read aloud, formal similarity between the letters of target and mask facilitated target recognition, as did associative similarity. Masking a target word by its own anagram also facilitated whole word report. In contrast, formal similarity was inhibitory rather than facilitatory of report when the target was spelled letter-by-letter, rather than read whole. This was true even for the same target words whose whole report was facilitated by formal similarity. A model to account for this reversal in the broader context of the neural substrate of reading is advanced. It is proposed that letter and word processing are fundamentally different in that letters are recognized by hierarchical feature analysis while words are stored and recognized wholistically by diffuse and redundant networks. Implications of the results for the study of reading are discussed.     

Treatment of urinary urgency and excessive frequency: a case study

A 39-year-old male presenting with a 5 year history of excessive urinary frequency and urgency was treated first with scheduling of urination, use of external urinary catheter and progressive muscular relaxation and then with a urinary retention training procedure. After the first set of procedures, urinary frequency decreased, whereas urgency increased slightly. After completion of retention training, both symptoms were alleviated. Overall, urinary frequency decreased from a baseline average of 14 urinations daily to a post-treatment average of 6.5 urinations per day. Urinary urgency decreased from a baseline average of 35 urges per day to a post-treatment average of 9.3 urges per day. Gains were maintained at 3 and 5 month follow-up.     

A CULTURAL DIFFERENCE IN VISUAL MEMORY: ON LE VOIT,ON NE LE VOIT PLUS

Further to the debate between Kearins (1978) and Drinkwater (1978), visual memory skills of Aboriginal and white Australian children were examined using Drinkwater's version of Kim's game with desert Aboriginal and rural white children. Older children remembered more than younger ones, and Aboriginal children recalled more natural objects than white children. There was no difference between the groups in recall of manufactured objects, nor between recall of manufactured and natural objects within each group. Aboriginal children remembered significantly more objects overall than white children when the task was first administered. On a second occasion, after a procedure designed to orient children towards the use of predominantly visual rather than verbal memorising strategies, there was no significant difference between the groups.     

Artistic style and personality in creative painters

The present study attempted to demonstrate a correspondence between artistic style and the personality of the creator. Personality style, defined as a cognitive-affective system of defenses and controls, was identified for 20 renowned painters through an analysis of their individual Rorschach protocols. Their creative work was classified independently by a jury of 4 persons (one art critic; two eminent painters and the junior author) into stylistic categories similar to those elaborated by the senior author for the Rorschach. The overall correspondence achieved was statistically significant (.72, p < .01), with individual correlations ranging from .75 to .86 (p < .01).     

The intuitive personologist revisited: A critique of dialectical person perception

A critical examination of dialectical person perception as advanced by Lamiell, Foss, Trierweiler, and Leffel, (1983) reveals some important problems both in its empirical basis and in the underlying model of the intuitive personologist. The present article discusses these problems and suggests some alternative conceptions of the intuitive personologist.     

Discrimination and generalization by rats of temporal stimuli lasting for minutes

In three experiments, rats learned to respond differentially to reinforced and nonreinforced trials when the length of the intertrial interval (ITI) predicted the trial outcome (reinforcement or nonreinforcement). Rats in control groups, for whom the length of the ITI did not predict the outcome, did not show differential performance on nonreinforced and reinforced trials. Generalization gradients obtained following discrimination training were comparable to those obtained following discrimination training with other types of discriminative stimuli. That is, groups which had shown differential performance in discrimination training yielded generalization gradients with fastest speeds at the previously reinforced ITIs, slowest speeds at the previously nonreinforced ITIs, and intermediate speeds at ITIs of intermediate length. Control groups yielded flat gradients across all ITIs tested. These effects were shown for relative time discrimination (short time = reinforcement, long time = nonreinforcement, or the reverse) and also for an absolute time discrimination (long and short time = reinforcement, middle time = nonreinforcement or the reverse). This method was effective for time duration measured in minutes rather than seconds, as is more commonly the case.