Fixed-interval limited-hold avoidance with and without signalled reinforcement

Rats trained to lever press on a fixed-interval limited-hold avoidance schedule maintained a pattern of responding similar to that maintained by fixed-interval limited-hold schedules of positive reinforcement. But this positively accelerated pattern of behavior was maintained only when the occurrence of reinforcement was signalled by the presentation of a brief flash of light. This result suggests that the discriminative function of the reinforcer in avoidance is less pronounced than the discriminative function of the reinforcer in escape or positive reinforcement. It also suggests that the distinction between positive reinforcement and avoidance is not superfluous. Although the schedule of reinforcement is an important variable in determining the pattern of behavior, other variables, such as the nature (i.e., stimulus presentation, termination, or omission) of the reinforcer, are also potent determinants of behavior.     

The effects of area and perimeter on detection rates

The detection of luminance increments in a homogeneously lighted field was studied as a function of the area and perimeter of the luminance increment. Sixteen targets representing all possible combinations of four values of area and four values of perimeter were foveally presented. Exposure durations were short (25 to 40 msec). Results of both an analysis of variance and linear discriminant analysis indicated that detection probability increases as area increases, but neither variations in perimeter nor perimeter-area combinations produced effects that were significant oyer the experiment as a whole. The linear discriminant analysis revealed individual differences in the effects of perimeter and area on detection probability. Results were contradictory to Kristofferson’s (1957) “element contribution theory” and gave only slight support to Hecht’s (Lamar, Hecht, Shlaer, & Hendley, 1947) “border-quantum theory.”     

My path into the profession

Contemporary Family Therapy -     

Semantic satiation in healthy young and older adults

In four experiments, semantic satiation was investigated in young and old adults. In the first two experiments, subjects were repeatedly presented a word (e.g.,dog) and then were presented a pair of words (e.g.,dog-cat ordog-chair) for a relatedness decision. The results of both experiments indicated that for the young adults, the relatedness effect (the difference between response latency on related and unrelated trials) decreased as a function of the number of times the satiated word was repeated, whereas for the older adults, there was no evidence of a decrease in the relatedness effect across repetitions of the satiated word. In the third experiment, we investigated whether phonological codes are also susceptible to satiation. This experiment was similar to the first two experiments with the exception that subjects made rhyme decisions (same-claim vs.same-dime) instead of semantic relatedness decisions. The results of this experiment did not yield any evidence of satiation for either the young adults or the older adults. The final experiment eliminated a simple decrease in attentional alertness or fatigue account of the semantic satiation effects found in the first two experiments. In this experiment, the repeated word was always unrelated to the pair of words presented for the relatedness decision. The results of this experiment did not yield any evidence of semantic satiation for either the young or the older adults. The discussion focuses on the mechanisms underlying semantic satiation and the implications of age-related changes in these mechanisms.     

Discursive logic towards a logic of rational discourse

Both logic and philosophy of science investigate formal aspects of scientific discourse, i.e. properties of (non-monotonic) consequence operations for discursive logic. In the present paper we handle two of them: paraconsistency and enthymematycity.Supported by grants from the Alexander von Humboldt-Stiftung, form the Fulbright-Foundation and from the Center for Philosophy of Science at the University of Pittsburgh.Presented byJan Zygmunt     

Anticipatory grief: The search for destiny

This paper explores the dynamics between a woman dying of cancer, the man she lived with for 37 years, and the clinician who worked with them during the final months of the woman's life. Psychoanalytic perspectives on transformational and transitional object-seeking as natural processes which aid the internalization of attachment to the one who is approaching death, the creation of a primary maternal preoccupation in the caretaker, the hospice as a holding environment, and the search for destiny as a metaphor for the work of anticipatory grief are integrated with the case-material.Presented at the American Academy of Religion Annual Meeting,Person, Culture and Religion Pre-session, November, 1991.     

Client Cognitive Responses as a Function of Quality of Counselor Verbal Responses

This study examined the relationship between high and low quality counselor responses in four response modes and client cognitions. Twenty-one university students participated in two sessions of brief counseling that included high and low quality counselor responses in paraphrasing, questioning, reflection of feeling, and self-disclosure. After each counseling session, participants used Kagan's (1975) interpersonal process recall method to report their cognitions in response to these counselor responses. Results indicated that the participants had more favorable cognitions toward the counselor associated with high quality counselor paraphrasing and reflection of feeling responses. Participants' cognitions directed toward themselves did not differ in response to any of the four high and low quality counselor responses. Implications of the results are discussed.