Multichannel communication in normal and delinquent families

Families containing adjudicated delinquents or nondisturbed adolescents were engaged in a laboratory interaction procedure aimed at assessing inconsistent (nonredundant) verbal-nonverbal communication patterns. Detailed analyses of verbal, facial, and auditory channels indicated higher rates of positive nonverbal, negative verbal communications in control versus delinquent families and in parent-parent versus parent-child interaction. Results are discussed in terms of the potential adaptive characteristics of such positive inconsistent communications.This article is based on a doctoral dissertation submitted by the first author, under the direction of the second author, to the University of Pittsburgh. Portions of this work were supported by NIMH Grant No. 2 RO1MH 25802 and NIAAA Grant No. 1 K01 AA00027 to Theodore Jacob.     

Sharp-edged vs. diffuse illusory circles: The effects of varying luminance

As had been found previously, one experiment demonstrated that reducing the luminance of a pattern that induced an abrupt-edged illusory figure increased mean ratings of that illusory effect. More importantly, the same result had not been found for a pattern that induced a diffuse illusory figure; in fact, a second experiment with such patterns produced a reliable tendency in the opposite direction. These results are at variance with the suggestion that an abrupt-edged illusory effect involves merely a minor variation in the boundary definition of a diffuse illusory lightness effect.     

The effect of lightness contrast on the colored Müller-Lyer illusion

Two subjects estimated the length of the central line in red-and blue Müller-Lyer figures that were viewed both foveally and parafoveally. The illusion figures were defined by either lightness and hue differences between figure and ground or by a hue difference alone. For both subjects, the figures defined solely by hue produced larger illusions. Since depth-cue scaling and other cognitive factors did not cause the enlargement, it was concluded that the robust, hue-produced illusions resulted from contour interactions generated within parvocellular channels that are specialized for coding color.