Computer signal detection by monitoring auditory evoked potentials

A digital computer, using a simple decision algorithm, attempted to determine when an acoustical signal had been presented to a cat by monitoring the amplitude of the evoked potentials (EP) at brainstem auditory nuclei. The signal-to-noise level at threshold and the shape and range of the decision model “psychometric functions” were similar to those obtained from humans in the same task. In addition, the detection performance obeys Weber’s law, the mean amplitude of the EP increases monotmonically with signal level, the variance of the amplitude is independent of both signal and noise level, and both the mean latency and the variance of the latency of the peaks decrease with increasing signal level. These findings suggest that the synchronization in firing of a population of single units plays a part in determining the amplitude of the EP. Interaural effects in detection performance were found at the inferior colliculus and, to a lesser extent, at the superior olive.     

Internal conflict,language, and metaphor: Implications for psychotherapy

The term conflict has only metaphorical validity when applied to internal dynamics, because an organism can never actually be at war with itself. Drawing upon Maturana's theory of living systems, we argue that the concept of conflict has been taken too literally by therapists and clients. Instead of eliminating conflict, we urge therapists to focus on the interpersonal implications of language habits and to explore with clients the options for more effective action in the social community.The authors would like to express their appreciation to G. Craig Caputo, Elsa R. Efran, Joseph Fiorito, Charles E. Gallagher, Christopher K. Germer, Richard J. Leffel, M. Penny Levin, Alan J. Lipman, Michael D. Lukens, Robert J. Lukens, and Richard Sadowsky, each of whom read earlier drafts and contributed valuable suggestions.     

Diurnal variation in the Positive Affects

We examined the circadian rhythm of two basic dimensions of mood—Positive Affect (PA) and Negative Affect (NA). Subjects were 196 college students in two studies who completed a mood rating form approximately seven times a day for 1 week. Significant diurnal variation was found to exist in overall Positive Affect, and in four component content areas, but not in Negative Affect. Specifically, all components of PA rose sharply from early morning until noon, remained relatively constant until 9 p.m., and then fell rapidly. The rise and fall of PA were quite robust across subjects, but the apparently static level of PA from noon to 9 p.m. was shown to result from averaging across marked individual differences in the time of peak PA. Various potential sources of these individual differences—“morningness-eveningness,” introversion-extraversion, and neuroticism/dysphoria—were investigated. Neither of the personality variables accounted for the significant variation in diurnal mood patterning, but clearly defined morning and evening types did show different patterns. Possible links between the mood pattern obtained and biologically based circadian rhythms, which have been postulated to be dysregulated in depression and mania, are discussed.     

A comparison of the environments of day care centers and group day care homes for 3 year olds

Caregiver-child interaction and social participation were compared in community-based day care centers and group day care homes for three year olds. Use of group day care homes made it possible to control for group size and adult-child ratio. Day care homes were found to be more structured in terms of curriculum, and more flexible in terms of overall schedule and social-emotional climate. Adult child interaction was of higher quality during structured periods in day care homes. Social participation was of higher quality in day care homes. The adult-child interaction in both types of day care was impersonal and neutral in affective tone.     

What is the “front” of a simple geometric form?

A total of 670 undergraduate Ss were tested in three studies conducted in an attempt to define a set of cues that minimally specify perceived “frontness” and “backness” of objects. In Experiment I, Ss were instructed to identify the “front” and “back” of printed squares to which no, one, or two circles were attached. In Experiment II, different Ss made the same kind of judgment to a wider range of geometric forms. In Experiment III, different Ss judged the direction of “imagined” movement of forms from Experiment I. The results indicated that the “front” and “back” are asymmetric opposite sides, with “front” the side most different from the rest and the side toward which the form is imagined to be moving.