Evidence for an error deadzone in compensatory tracking

Humans and monkeys show intermittent arm movements while tracking moving targets. This intermittency has been explained by postulating either a psychological refractory period after each movement and/or an error deadzone, an area surrounding the target within which movements are not initiated. We present a technique to detect and quantify the size of this deadzone, using a compensatory tracking paradigm that distinguishes it from a psychological refractory period. An artificial deadzone of variable size was added around a visual target displayed on a computer screen. While the subject was within this area, he received visual feedback that showed him to be directly on target. The presence of this artificial deadzone could affect tracking performance only if it exceeded the size of his intrinsic deadzone. Therefore, the size of artificial deadzone at which performance began to be affected revealed the size of the intrinsic deadzone. Measured at the subjects' eye, the deadzone was found to vary between 0.06 and 0.38 degrees, depending on the tracking task and viewing conditions; on the screen, this range was 1.3 mm to 3.3 mm. It increased with increasing speed of the target, with increasing viewing distance, and when the amplitude of the movement required was reduced. However, the deadzone size was not significantly correlated with the subjects' level of performance. We conclude that an intrinsic deadzone exists during compensatory tracking, and we suggest that its size is set by a cognitive process not simply related to the difficulty of the tracking task.     

Affect, personality, and social activity.

These studies examined relations between social activity and state and trait measures of Positive and Negative Affect. In Study 1 Ss completed scales relevant to 3-factor models of personality and a weekly mood and social activity questionnaire for 13 weeks. In Study 2 Ss completed measures of the 5-factor model of personality and a daily mood and social activity survey for 6-7 weeks. In within- and between-Ss analyses, socializing correlated significantly with state measures of Positive Affect and with trait measures of Extraversion/Positive Emotionality. These relations were relatively general across various types of positive affect and social events; however, specific types of social events also were differentially related to affect. In contrast, social activity had no consistent association with measures of Negative Affect or the other personality dimensions. The results support a temperamental view of Extraversion.     

Repression at encoding: discrete appraisals of emotional stimuli.

In previous research, the emotions associated with repressors' memorial representations were found to be more discrete than those associated with nonrepressors'. In each of the 3 experiments reported here, repressive discreteness was apparent in repressors' appraisals of emotional stimuli at the time they were encoded. In 1 experiment, Ss appraised individual facial expressions of emotion. Repressors judged the dominant emotions in these faces as no less intense than did nonrepressors, but they appraised the blend of nondominant emotions as less intense than did nonrepressors. In the remaining 2 experiments, Ss appraised crowds of emotional faces as well as crowds of geometric shapes. In both crowd experiments, the repressive discreteness was evident in appraisals of crowds of emotional faces but not in appraisals of crowds of geometric shapes. The repressive discreteness effect did not appear to reflect a general repressor-nonrepressor difference in the appraisal of stimulus features. Rather, the results suggested that repressive discreteness may be constrained to appraisals of emotions.     

Rorschach object relations of adolescents who committed homicide.

We investigated the object relations of adolescents who committed homicide. A clinical sample of 55 adolescents who committed homicide did not differ from a comparison group of nonviolent delinquents on Rorschach measures of object differentiation, mutuality of autonomy, and aggressive content. However, the subgroup of adolescents who committed homicides in the context of another crime (e.g., robbery or burglary) did manifest significantly lower object relations (poorer object differentiation and more victim responses) than the subgroup of adolescents whose homicides were committed in the context of an interpersonal conflict or dispute with the victim. These findings support the need for differentiated classification of violent individuals as urged by Megargee (1970) over 20 years ago.     

Compartmentalization of positive and negative self-knowledge: keeping bad apples out of the bunch.

Three studies examined whether categorical organization of knowledge about the self explains variance in self-esteem and depression beyond that which is accounted for by sheer amount of positive or negative content. Compartmentalization is the tendency to organize positive and negative knowledge about the self into separate, uniformly valenced categories (self-aspects). As long as positive self-aspects are activated, access to negative information should be minimized. Compartmentalization was associated with high self-esteem and low depression scores for individuals whose positive self-aspects were important; when negative self-aspects were important, compartmentalization was correlated with low self-esteem and high depression scores. An analysis of self-aspect labels showed that individuals with compartmentalized organization define negative self-aspects in especially narrow terms. A possible relationship between compartmentalized organization and cognitive complexity is discussed.     

Sensory and affective components of pain: separation and synthesis.

It has become increasingly accepted that pain is not simply a sensation generated by nociceptors, but a perceptual phenomenon with particular emotional qualities. The purpose of this article is to bring together vastly different streams of research on the divisibility of pain into sensory and affective components. Empirical evidence for this divisibility is drawn from recent studies using multivariate statistics, signal detection theory, and unidimensional scaling. An important conclusion is that separable though pain components may be, they are not necessarily independent. In critiquing previous research, new criteria are derived for partitioning pain into sensory and affective components. Finally, speculations are offered as to how these same components might be synthesized on the basis of theories of perceptual organization.     

Depression and immunocompetence: a review of the literature.

Recent evidence suggests that there is a relationship between depression and immunity. On the basis of these studies, it has been argued that depressed mood may increase susceptibility to disease by means of aberrations occurring within the immune system. Empirical research investigating the relationship between depression and immunity is reviewed here. Studies examining both clinical and nonclinical manifestations of depression are discussed and evaluated. This review reveals that indexes of immunocompetence are lower among people exhibiting depressive symptomology and suggests that immune alterations may be more related to dysphoric mood than to specific situations or events. Alternative hypotheses accounting for links between depressed affect and altered immune states are provided, and suggestions for future research are offered.     

Problems in recent tests of two cognitive theories of panic.

Four problems in five recent tests of two cognitive theories of panic are discussed: (a) the ambiguity and indistinguishability of the 'body sensations' and 'cognitions' concepts; (b) the uncertain meaning of 'meaningful relationships'; (c) problems arising from differences in Clark's (Behaviour Research and Therapy, 24, 461-470, 1986) theory and Goldstein and Chambless' (Behavior Therapy, 9, 47-59, 1978) theory; (d) the ambiguity of correlational data. Some desiderata for future research on these theories are proposed.     

Predictors of short-term treatment outcome in bulimia nervosa inpatients.

Recent studies, mostly performed on bulimic outpatients, did not find consistent predictors of treatment outcome in bulimia nervosa. This is the first study to investigate anamnestic and clinical factors predictive of the short-term outcome of hospital treatment in 31 female bulimia nervosa patients with a mean age of 22.9 yr. Treatment outcome was assessed by several self-rating instruments measuring different features of the specific and unspecific psychopathology of bulimia nervosa. The most relevant predictors of the outcome of the 8-week hospital treatment were duration of previous inpatient treatments for bulimia, the intensity of anorexic tendency and the pretreatment level of depression. The majority of predictors tested did not show a strong relationship to treatment outcome. The findings are discussed in relation to results of other studies as well as to possible implications for treatment and research.