The nature of adaptation in distance perception based on oculomotor cues

In previous work by the senior authors, brief adaptation to glasses that changed the accommodation and convergence with which objects were seen resulted in large alterations in size perception. Here, two further effects of such adaptation are reported: alterations in stereoscopic depth perception and a change when distance is represented by a response of S’s arm. We believe that the three effects are manifestations of one primary effect, an alteration of the relation between accommodation and convergence on the one hand and the distance they represent in the nervous system (registered distance) on the other. This view was supported by the results of two experiments, each of which demonstrated that the alterations in stereoscopic depth perception could be obtained after adaptation periods which had provided no opportunity to use stereoscopic vision, and that the adaptation effect was larger for depth perception than for size perception when it was obtained under the same conditions; the latter finding was expected if both effects resulted from the same change in registered distance. In three of the five experiments here reported, the variety of cues that could represent veridical distance during the adaptation period was limited. In one condition of adaptation, only the pattern of growth of the retinal images of objects that S approached and the kinesthetic cues for S’s locomotion served as cues to veridical distance. In two other conditions S remained immobile. In one of these, only the perspective distortion in the projection of the scene that S viewed mediated veridical distance, and in the other one familiar objects of normal size were successively illuminated in an otherwise totally dark field, conditions from which opportunities to use stereoscopic vision were again absent. After exposure to each of these adaptation conditions, adaptive changes in perceived size and larger ones in perceived stereoscopic depth were obtained. Because we found that familiar size may serve as the sole indicator of veridical distance in an adaptation process, we concluded that it can function as a perceptual as distinguished from an inferential cue to distance.     

Increased eating in rats deprived of running

Daily food intake in rats was temporarily reduced by the introduction of an activity wheel and temporarily increased by the subsequent removal of the wheel. When this outcome is coupled with the positive relation between food deprivation and running—and food deprivation is seen as a loss of eating rather than as a physiological state—there is the suggestion that the total behavior output of the organism may be regulated as such. Specifically, when the rat is deprived of a behavior that recurrently comprises a large part of its total daily activity, an increase may occur in some other behavior.     

Ethical Issues in Consultation,Associate Professor and Director

Consulting relationships differ from traditional counseling and psychotherapeutic relationships in several fundamental ways. These differences require special consideration in evaluating ethical questions and conflicts, identifying ethical parameters within any given situation, and using existing ethical guidelines in determining appropriate courses of action. Currently, formal guidelines specific to the practice of consultation are not available, and existing codes of ethics for the helping professions provide only limited guidance for consultation practice. Consequently, consultants bear a heavy personal responsibility for the consequences of their professional decisions and actions. In this article the author reviews several important ethical issues relevant to consultation and examines their implications for consultation practice.     

Anxiety and the spelling and use in sentences of threat/neutral homophones

The disambiguation of threat/neutral homophones was investigated in high- and low-trait anxiety subjects who had been exposed to either a positive or a negative mood manipulation procedure. Subjects were required first to spell each auditorily presented word and second, to generate and speak a sentence using the word. Difference indices were calculated for the spelling and the sentence usage data, i.e. the number of threat minus neutral interpretations. Examination of these indices revealed that subjects exposed to the negative mood manipulation procedure produced relatively more threat than neutral interpretations (for both spelling and sentence usage) than did subjects exposed to the positive mood manipulation procedure. Multiple regression analyses revealed that both the trait anxiety and mood manipulation variables contributed significantly to the prediction of the difference index on the spelling task. In the analysis of the use of homophones in sentences, only the mood manipulation variable contributed significantly to the prediction of the difference index on the sentence usage task.     

Family psychopathology: Cross training graduate marital and family therapy students in family assessment and psychiatric nosology

The structure of a course entitled Family Therapy with Major Psychopathology taught annually in the Mercer University Graduate Marriage and Family Therapy Program is presented. An epistemological presentation regarding the interface of psychiatric nosology and family systems assessment is discussed. Methods of diagnosing and assessing dysfunctional family systems are presented and training in individual psychiatric nosology is discussed, with particular attention given to family systems dysfunction as an etiological factor in the development of individual psychopathology. Learning techniques are discussed including lecture, discussion, case presentations, readings, and testing methods.     

Distractor clustering enhances detection speed and accuracy during selective listening

The effects of distractor clustering on target detection were examined in two experiments in which subjects attended to binaural tone bursts of one frequency while ignoring distracting tones of two competing frequencies. The subjects pressed a button in response to occasional target tones of longer duration (Experiment 1) or increased loudness (Experiment 2). In evenly spaced conditions, attended and distractor frequencies differed by 6 and 12 semitones, respectively (e.g., 2096-Hz targets vs. 1482- and 1048-Hz distractors). In clustered conditions, distractor frequencies were grouped; attended tones differed from the distractors by 6 and 7 semitones, respectively (e.g., 2096-Hz targets vs. 1482- and 1400-Hz distractors). The tones were presented in randomized sequences at fixed or random stimulus onset asynchronies (SOAs). In both experiments, clustering of the unattended frequencies improved the detectability of targets and speeded target reaction times, Similar effects were found at fixed and variable SO As. Results from the analysis of stimulus sequence suggest that clustering improved performance primarily by reducing the interference caused by distractors that immediately preceded the target.     

INCREASING CALORIE CONSUMPTION IN CHILDREN WITH CYSTIC FIBROSIS: REPLICATION WITH 2-YEAR FOLLOW-UP

Three mildly malnourished children with cystic fibrosis and their parents participated in a behavioral group-treatment program that focused on promoting and maintaining increased calorie consumption. Treatment included nutritional education, gradually increasing calorie goals, contingency management, and relaxation training, and was evaluated in a multiple baseline design across four meals. Children's calorie intake increased across meals, and total calorie intake was 32% to 60% above baseline at posttreatment. Increased calorie consumption was maintained at the 96-week follow-up (2 years posttreatment). The children's growth rates in weight and height were greater during the 2 years following treatment than the year prior to treatment. Increases in pace of eating and calories consumed per minute were also observed 1 year posttreatment. These findings replicated and extended earlier research supporting the efficacy of behavioral intervention in the treatment of malnutrition in children with cystic fibrosis.