A behavioral link between the oculomotor and cardiovascular systems

Although the eyes and the heart serve very different purposes, each receives autonomic innervation. Capitalizing on recent theoretical and technological innovations in the understanding and assessment of oculomotor and cardiovascular behavior, three experiments measured behavioral covariation between the oculomotor and cardiovascular systems. Measures of dark focus and dark vergence indexed oculomotor tone, and the spectral decomposition of variations in heart rate indexed cardiovascular control mechanisms. In Experiment 1, individual differences in cardiovascular parameters could predict individuals’ dark vergence (R²=.806) but not their dark focus (R²=.404). In Experiment 2, the same parameters were measured from subjects who experience either panic attacks (n=11) or blood phobia (n=9). Heart rate was positively correlated with dark vergence and the two subject groups were separable based on both oculomotor and cardiovascular variables. Using a within-subjects approach, Experiment 3 found that both dark vergence and dark focus tended to be nearer during sympathetic dominance of the heart than during parasympathetic dominance, within-subjects variations in cardiovascular parameters could predict dark focus, and between-subjects variations in interbeat intervals could predict dark vergence. Shared patterns of autonomic activation may be responsible for this eye-heart link.     

Tests of randomness for pseudorandom number generators

This study examined the “randomness” of the numbers generated by the VIC-20 computer. Using eight standard tests, it was determined that the numbers provided by the VIC-20 are adequately random for practical purposes. The tests are applicable to other computer systems and provide a general means for evaluating random-number generators.     

Are there limits to binaural additivity of loudness?

In recent years there has been notable interest in additive models of sensory integration. Binaural additivity has emerged as a main hypothesis in the loudness-scaling literature and has recently been asserted by authors using an axiomatic approach to psychophysics. Restrictions of the range of stimuli used in the majority of former experiments, and inherent weaknesses of the axiomatic study by Levelt, Riemersma, and Bunt (1972) are discussed as providing reasons for the present investigation. A limited binaural additivity (LBA) model is proposed that assumes contralateral binaural inhibition for interaural intensity differences that exceed a critical level. Experimental data are reported for 12 subjects in a loudness-matching task designed to test the axioms of cancellation and of commutativity, both necessary to the existence of strict binaural additivity. In a 2 X 2 design, frequencies of 200 Hz and 2 kHz were used, and mean intensity levels were 20 dB apart. Additivity was found violated in 33 out of 48 possible tests. The LBA model is shown to predict the systematic nonadditivity in the loudness judgments and to conform to results from other studies.     

Setting phenotypes in a mutual help organization: Expanding behavior setting theory

Expands Barker's theory of behavior settings by proposing an additional method of classifying settings based on their functional/behavioral aspects--the setting phenotype. Although behavior setting theory has been widely hailed as a revolutionary contribution to behavioral science, it has had limited impact on general psychology. This may be due in part to a reliance on a purely structural method of classifying behavior settings--the setting genotype. Behavioral data were collected from 510 meetings of 13 self-help groups from a mutual help organization for persons with problems in living. A cluster analysis was performed to uncover meaningful behavioral patterns among the groups. Four phenotypes were identified: personal, impersonal, small talk, and advising. Mutual help group phenotype was found to be related to a set of setting characteristics as well as to overall rated change of group members. The results are discussed in light of the significance of the phenotype construct for making behavior setting theory more relevant for social scientists.     

A study of language functioning in Alzheimer patients

Language functioning in Alzheimer's disease is reviewed and the performance of 25 Alzheimer patients on a standard battery is reported. All these hospitalized patients were aphasic to some degree. As a group, they differed from normals on all language variables, and from stroke patients in terms of higher fluency and lower comprehension. Spontaneous speech showed high incidence of circumlocutions and semantic jargon, but no phonemic paraphasias or target approximations. Syllabic perseverations, shouting, inappropriate laughter, and mutism were late-appearing features. Transcortical Sensory, and Wernicke's aphasias were frequent, but Broca's and Transcortical Motor aphasias notably absent. Extent of language impairment correlated with current length of hospitalization but not age. Reading, writing, and performance scores except praxis, were lower than oral language scores. Findings were discussed in relation to previous results, methodology, and language organization in the brain.     

The effect of landmark features on mental rotation times

By varying what we take to be the saliency oflandmarks (which are cues to location and orientation that are unique and visible from a distance), the slopes and intercepts of the time/angle function in the "mental rotation" task were caused to vary accordingly.