Prehension in children and adults: The effects of object size

Studies of visually goal-directed arm movements in adults have shown that various task constraints such as intention, context, and object properties affect different kinematic characteristics of the movement components (Jeannerod, 1984; MacKenzie et al., 1987; Marteniuk et al., 1987, 1990; Paulignan et al., 1991; Soechting, 1984). The purpose of the present study was to compare the effects of varying object size on the kinematics of reaching and grasping in both children and adults. Five children aged 9–10 years and five adults aged 18–24 years reached for and grasped three different sized cubes. Results revealed that object size had the same effect on the planning and control of reaching and grasping movements in children as in adults. Unlike adults, however, children in this age range spent more time in deceleration and reached peak aperture much later in the movement trajectory. The results were interpreted as immature integration of the visual and proprioceptive systems in 9–10 year olds. The implications of these findings for further examining developmental trends in prehension are discussed.PsycINFO classification: 2330     

Relationship of Parental Alcoholism to Family-of-Origin Functioning and Current Marital Satisfaction

This study examined the relationship between parental alcoholism, family-of-origin functioning, and current marital satisfaction. Results indicated family-of-origin functioning is positively related to marital satisfaction. In addition, individuals with alcoholic parents reported lower family-of-origin functioning, and an interaction between gender and parental alcoholism was found for marital satisfaction.     

Reaction time and movement time as measures of stimulus evaluation and response processes

Reaction time has been divided into the time to initiate a response (RT) and the time to execute the motor response (MT) in many chronometric studies of intelligence. Our purpose was to determine which cognitive processes are reflected by RT and MT. To accomplish this, the latency of the P300 wave of the event-related potential was recorded concurrently with RT and MT measures in three experiments. P300 latency reflects the duration of stimulus evaluation relatively independently of response processes. In the first experiment, a Sternberg memory task was employed to manipulate stimulus classification requirements. In the second, the subjects' emphasis on either speed or accuracy of responding was examined during a task that also manipulated stimulus evaluation time. In the third experiment, a Stroop-like task was used to examine response processes. RT and P300 latency varied with manipulations of stimulus evaluation time, whereas MT varied with difficulty of motor execution. MT was also affected by stimulus classification processes. Both RT and MT were sensitive to processes involved in response bias and preparation. The possibility that the correlations of RT and MT with measures of intelligence are due to effects on a common stage of information processing cannot be rejected in the light of these results.     

Of Orchids,insects, and natural theology: Timing,tactics, and cultural critique in darwin's post-“Origin” strategy

This essay examines the relation of Darwin's orchids book to a central persuasive flaw in theOrigin: Its inability to give variation sufficient presence to break the hold of design in the mind of the reader. Darwin characterized the orchids book as a flank movement on the enemy; this essay identifies the enemy as Paley's natural theology and the flank as thetopoi, maxims, and habits of perception that led Darwin's colleagues and contemporaries to see design in nature. Moreover, this essay examines three aspects of rhetorical timing pertinent toOrchids - time askairos, time as adequate duration, and time as transformation - and then relates those features to Robert Cox's Heideggerian logic of repetition, disavowal, and transcendence. The essay concludes with implications of the tactical and temporal aspects of Darwin's reasoning for understanding both the logic of science and of Darwin as a rhetorical artist.An earlier version of this essay appeared in the Proceedings of the Sixth SCA/AFA Conference on Argumentation.     

Ontogeny of behavioral arousal: the role of environmental stimuli

During the course of ontogenesis the developing rat has been reported to pass through a transient period of intense behavioral arousal which peaks at 15 days of age, a phenomenon that has been interpreted to reflect a sequential caudal to rostral development of excitatory and inhibitory systems in the mammalian brain. In a series of four experiments it was shown (a) that this period of intense hyperactivity occurs only when the animal is tested alone in an unfamiliar environment, that the degree of arousal is proportional to the dissimilarity between the home cage and the test environment, and that isolation per se is insufficient to elicit the arousal response; (b) that environmental temperature has a minimal influence on the degree of behavioral arousal seen in either familiar of unfamiliar environments; (c) that unlearned responses to pheromonal or other naturally occurring nest odors do not suppress the high levels of locomotor activity evoked by unfamiliar environments in the 15-day old rat pup; and (d) that it is fear or distress evoked by the unfamiliar environment rather than curiosity that underlies this developmental phenomenon. It is concluded that the sequential increase and decrease in locomotor activity that occurs during ontogenesis cannot be used to support the principle of caudal to rostral development of excitatory and inhibitory centers in the central nervous system.     

MMPI identification of nonrehabilitants among disabled veterans.

Utilized the Minnesota Multiphasic Personality Inventory (MMPI) with IQ scores and selected biographic data to identify drop-outs in a Veterans Administration vocational rehabilitation program. Subjects were 61 male disabled veterans. Data were collected at VA Hospital Richmond, Virginia, between September 1973 and September 1974. Follow-up six months after entrance into training utilized persistence in training or employment as success criteria. Multivariate analysis identified 32 of 33 successful and 25 of 28 unsuccessful subjects with p less than .001. Factor analysis of the best predictors identified MMPI Psychopathic deviate (Pd) Hypomania (Ma), and Lie (L) scales which was interpreted to be a social adjustment factor. Four other factors were identified. Results indicated the MMPI was a useful instrument in the identification of disabled veterans who were likely to experience difficulty in post-hospital vocational rehabilitation.     

The primary personality factors of Hawaiian, middle adolescents

To determine whether the primary personality factors of Hawaiian, middle adolescents were the same as those Cattell postulated in 1970, for adolescents on the mainland of the United States, and in 1974 for adolescents in Germany, a personality questionnaire representing those factors completed by 694 Hawaiian, middle adolescents (M age = 15.9 yr.) was factor analyzed. Despite the analysis adhering closely to the recommendations of Cattell stated in 1973 and 1978, the eight factors derived are not the set of primary factors postulated for the other populations. Six of them do appear to be, however, primary factors within a set of seven reported in 1988 for a younger population of Hawaiian, early adolescents. In addition, these six factors also appear to be similar to the major constructs in the psychoanalytic theories of Freud and Horney.     

The effects of a self-management treatment package on daily step count in university students with depressive symptoms

Research demonstrates that exercise can decrease depressive symptoms, yet it is infrequently prescribed as an intervention. Self-management techniques offer an effective and cost-efficient approach to increase engagement in physical activity. The purpose of this study was to evaluate the efficacy of goal setting, self-monitoring, and feedback for increasing daily step count in university students (N = 4) reporting depressive symptoms. The treatment was efficacious for increasing steps for three participants with varying levels of consistency. All participants showed a decrease in some depression symptoms on the University Student Depression Inventory. Expert ratings on the Clinical Global Impression Scale indicated improvement in global functioning for three participants. Additional research is needed to determine the efficacy of this intervention package for increasing daily steps and the relation to depression symptoms.