Use of the Sleep Assessment Device (Kelley and Lichstein, 1980) to validate insomniacs' self-report of sleep pattern

A comparison is presented of insomniacs' self-reported sleep pattern and objectively monitored sleep using the Sleep Assessment Device (SAD; Kelley & Lichstein, 1980). Analysis of 110 subject nights revealed modest but significant subjective overestimates of both sleep latency and sleep duration which were accounted for by the demands of the task (i.e., longer time periods are harder to estimate accurately). Correlations between self-report and SAD measures were, however, consistently high, suggesting that self-report may be a valid index of sleep disturbance. Results are discussed with reference to the clinician's task in evaluating sleep complaints.This research stury was supported by a grant from the Research Fund of Lanarkshire Health Board, Scotland.     

Commentary on high-performance computing and human vision II: Virtual reality and eyeball tracking

Visualization of scientific data that are not normally visible can be greatly enhanced by understanding human visual perception. Mars the Movie illustrated the use of stereo resolution for producing realistic vistas of the Mars surface. The real-time recording and analysis of eyeball-tracking data is another example of human vision research which benefits from high-performance computing. Currently the bottleneck is not in the hardware but in the available software to transform data efficiently.     

Priming on verbal perceptual tests: Roles of lexical,surface, and conceptual processes

According to a lexical-access hypothesis, priming on verbal-completion tests requires previous access to higher-order nodes such as morphemes or words. In two experiments, subjects studied words presented in printed color, either by reading the words or by naming the printed colors. In Experiment 2, some of the words were to be ignored in both study conditions. The words presented in Experiment 2 were either conceptually related or unrelated to each other. And the cues in the test phase for repeated targets were either printed in the studied color or in a different color. In both experiments, the word stems of nouns studied and of new targets were presented with word-completion instructions (implicit test of memory). Consistent with the hypothesis, the amount of priming obtained was greater in the reading than in the color-naming condition. The least amount of priming was observed for targets that were to be ignored at study. In addition, Experiment 2 showed considerable effects of surface similarity (i.e., stronger priming effects with cues whose color was not changed from the study to the test phase) and some effects of conceptual processing, as was indicated by different amounts of priming for unrelated and for related nouns. Because these two effects were observed with both types of study task, it is concluded that perceptual and conceptual processes may make independent contributions to priming effects in verbal perceptual tests. This conclusion modifies and extends the original hypothesis, according to which previous lexical access is required in order to obtain effects of perceptual or conceptual processes on the priming scores.     

Implicit memory for textual materials

As a word moves from isolation in a list to being contextually bound in meaningful discourse, its probability of priming in tests of implicit memory decreases. The present experiments explore whether considerable priming effects can be revealed with conceptual tests of implicit memory as compared to perceptual tests. In the study phase, meaningful actions were described within a coherent text. In Experiment 1 subjects elaborated half of the actions by visual imagery. In Experiment 2, subjects elaborated the actions by enacting them symbolically. In both experiments, subjects in a control condition were simply required to read the same activities. In Experiment 2, a further group of subjects had to detect orthographic errors. The results demonstrated reliable effects of implicit memory in terms of associations with verbs repeated from the studied text. This form of repetition priming for textual materials in a conceptual test of implicit memory was enhanced by both types of elaboration. A word-stem completion task for the same targets revealed a less pronounced and inconsistent priming effect, uninfluenced by both types of elaboration. But the latter form of perceptual priming was found to be more pronounced within the error-detection condition. Measures of explicit memory showed similar effects of elaborative encoding conditions but there were some dissimilarities to measures of implicit memory, too. In general and in accordance with a transfer-appropriate processing view, conceptual tests rather than perceptual tests may be more suitable for detecting effects of implicit memory within the domain of text processing.     

Book reviews

History of Islamic Philosophy Seyyed Hossein Nasr & Oliver Leaman, Editors, 1996 London, Routledge Part I, xx+ 780 pp., Part II, xiv + 428 pp., hb ISBN 0415 05 6675, £120.00

Early Advaita Vedānta and Buddhism: the Mahāyāna context of the Gaudapādiya‐Kārikā Richard King, 1995 Albany, State University of New York Press xii + 341 pp., pb $19.95

Vaisnavism: its philosophy, theology and religious discipline S.M. Srinwasa Chari, 1994 Delhi, Motilal Banarsidass xxxviii + 383 pp., pb Rs. 350

Vaisnavism: contemporary scholars discuss the Gaudiya tradition Steven J. Rosen (Ed.), 1992 Delhi, Motilal Banarsidass, 1994 ix + 354 pp., pb Rs. 160

Cultural Realism: strategic culture and grand strategy in Chinese history Alastair Iain Johnston, 1995 Princeton, Princeton University Press xiii + 367 pp., hb ISBN 0691029962, $39.50

Laughing at the Tao: debates among Buddhists and Taoists in medieval China Livia Kohn, 1995 Princeton, Princeton University Press xii + 281 pp. hb (price not given)

Pantheism. A Non‐theistic Concept of Deity Michael P. Levine, 1994 London, Routledge xii + 388 pp., hb £45 ISBN 0415070643     

Neuroendocrine hemisphere asymmetries: Salivary cortisol secretion during lateralized viewing of emotion-related and neutral films

The study set out to examine whether the cerebral hemispheres differ in their ability to regulate cortisol secretion during emotion-related situations. One hundred twenty-three adult subjects were shown either an emotionally aversive or a neutral film in the left or right hemisphere by means of a technique for lateralizing visual input that allows prolonged viewing while permitting free ocular scanning. The film-related changes of cortisol secretion were determined by salivary cortisol radioimmunoassay. Right hemispheric viewing of the emotionally aversive film resulted in a significantly higher increase of cortisol secretion than left hemispheric viewing of the same film. No such differences were observed with respect to the neutral film. Comparing the effects of the two films separately for each hemisphere revealed that only the right hemisphere was able to respond neuroendocrinologically in a different manner to the emotional and the neutral film. Therefore, it is concluded that cortical regulation of cortisol secretion in emotion-related situations is under primary control of the right hemisphere. The potential implications of asymmetric control of cortisol secretion with respect to the pathogenesis of psychosomatic and immunological disorders are discussed.     

University students' priorities: Life goals vs. relationships

To assess the importance of life goals and relationships, a specially designed Life Goals Scale was administered to 303 university students (200 women and 103 men). Women's average ratings for relationships exceeded those of men. Men and women did not differ in average importance ratings of goals nor in tendency to sacrifice goals for a heterosexual relationship. Seventy-three percent were willing to sacrifice a majority of their goals for the relationship. The goal vs. relationship choices were influenced by sex role orientation, by dating status, and by the importance of marriage. Gender, age, year in school, parents' marital status, and grade point average were unrelated to goal vs. relationship choices. Stepwise multiple regression analyses indicated different predictors of goal vs. relationship choices for men and women.     

Linear systems analysis of infant visual pattern preferences

Karmel's check-pattern preference data for 13-week-old infants were reanalyzed using linear systems analysis. The two-dimensional Fourier amplitude spectrum was calculated for each of his eight checkerboard and random check patterns. The mean contrast sensitivity data for 3-month-old infants of Banks and Salapatek and the spatial frequency amplitudes of the patterns were used to derive three metrics to predict the looking times observed by Karmel. One was based on the sensitivity of the visual system to the single pattern component highest above threshold (maximum amplitude), the second was based on the total amount of pattern energy above threshold (total summation), and the third was based on the maximum amplitude with summation over nearby spatial frequency components (limited summation). The predictive power of the maximum amplitude and the total summation metrics depended on whether the pattern type was checkerboard or random check. The limited summation metric predicted looking times well for both pattern types. A linear function of the logarithm of the limited summation metric accounted for 91% of the total variance in looking time.