Patterns of movement in the first 6 months of life: new directions

The field of infant perceptual development has relied heavily on the preferential-looking and habituation paradigms. Despite the obvious advantages of employing standardized methodologies, there is a need to study how perceptual variables give rise to and guide action beginning in the neonatal period. It is argued here that, in the first 5 months of life, it is important to distinguish reflexive patterns of movement from voluntary and cortically controlled patterns. Some criteria are defined. This paper describes three experiments which utilized movement counters to record developmental changes in the frequency and synchrony of limb movements in infants under 5 months. The results show that there is a general increase in frequency of limb movements from 1 to 5 months, but with a plateau or even a decrease in activity from the middle of the third month to the end of the fourth month. It was also demonstrated that synchrony scores (co-activation) for pairs of limbs showed significant increases from 1 month to 5 months. Finally, in all three experiments the presentation of an attractive toy resulted in suppression of activity. The results of the three experiments are interpreted to measure a gradual increase in cortically controlled movement patterns.     

Visual search along the colour dimension

Subjects searched for a chromatic target among coloured background items. With low target-background chromatic similarity, response latencies remained uniformly short whether the target was present or not and whether the items were chromatically homogeneous or not. Latencies increased with increases in target-background similarity and were longest with heterogeneous backgrounds, with which the effects of trial type also became manifest. We employed Treisman's model of visual search to account for these findings. In particular, we suggest that similarity increases forced a shift from a preattentive to an attentive search, the latter being importantly shaped by the background's level of chromatic variance.     

Neuronal models of cognitive functions

Understanding the neural bases of cognition has become a scientifically tractable problem, and neurally plausible models are proposed to establish a causal link between biological structure and cognitive function. To this end, levels of organization have to be defined within the functional architecture of neuronal systems. Transitions from any one of these interacting levels to the next are viewed in an evolutionary perspective. They are assumed to involve: (1) the production of multiple transient variations and (2) the selection of some of them by higher levels via the interaction with the outside world. The time-scale of these "evolutions" is expected to differ from one level to the other. In the course of development and in the adult this internal evolution is epigenetic and does not require alteration of the structure of the genome. A selective stabilization (and elimination) of synaptic connections by spontaneous and/or evoked activity in developing neuronal networks is postulated to contribute to the shaping of the adult connectivity within an envelope of genetically encoded forms. At a higher level, models of mental representations, as states of activity of defined populations of neurons, are discussed in terms of statistical physics, and their storage is viewed as a process of selection among variable and transient pre-representations. Theoretical models illustrate that cognitive functions such as short-term memory and handling of temporal sequences may be constrained by "microscopic" physical parameters. Finally, speculations are offered about plausible neuronal models and selectionist implementations of intentions.     

Violence and the systemic view: the problem of power

Violence is a strikingly lineal concept that is difficult to address from a systemic perspective. Bateson's epistemological disqualification of the concept of power is often understood to imply a corresponding systemic disqualification of the concept of violence. This position is examined in light of recent feminist criticism. It is argued that (a) violence and power belong essentially to the domain of human experience and (b) human experience cannot be invalidated by theory. Accordingly, it is suggested that the (appropriate) invalidation of power and violence in the domain of systemic explanation should probably be understood both as a deliberate choice that necessarily follows from adopting a systemic perspective, and as a fundamental limitation of that perspective. In neither case, however, should the systemic view be considered to be a valid disqualification of the human experience of violence and power.     

COGNITIVE EFFECTS OF LOGO AMONG BLACK AND WHITE ZIMBABWEAN GIRLS AND BOYS

The cognitive effects of LOGO were examined among 11–12-year-old black and white Zimbabwean girls and boys. Fifty-two experimental group children were exposed to a BBC LOGO programme with a screen turtle. Forty-one control group children received no exposure to computers at school. Pre-tests on four WISC-R subscales were held in January, 1987 and post-tests on the same four WISC-R subscales were held in November/December, 1987. The data were analyzed with multivariate analysis of covariance, using pre-test scores as the covariate. The results suggested that children in the experimental group did better on the WISC-R Arithmetic scale and that black girls exposed to LOGO showed particular gains in spatial reasoning, as measured by the WISC-R Block Design scale. It is concluded that LOGO appears to facilitate cognitive growth. Methodological limitations of the present study are discussed and suggestions for future research are presented.     

Relations of sociotropic and autonomous personality characteristics to specific symptoms in depressed patients

A number of writers have suggested that two sets of personality characteristics are associated both with vulnerabilities to depression in response to different classes of events and with different clinical presentations of depression. The present study examined the relations between levels of sociotropic and autonomous personality characteristics and specific, theoretically derived clusters of symptoms in 80 unipolar depressed patients. As was predicted, sociotropy was related to the cluster of symptoms associated with the concept of anxious-reactive depression and was unrelated to the autonomous symptoms cluster. In contrast, the predicted relations of autonomous personality characteristics and symptoms were not found. These results support the idea that the symptom picture in depression may be related to personality characteristics, but they also suggest that the measurement of autonomy may require revision.     

From rarity to evaluative extremity: effects of prevalence information on evaluations of positive and negative characteristics

Experiments showed a scarcity principle in evaluative judgments such that the identical characteristic is evaluated more extremely the lower its perceived prevalence. In Study 1, Ss evaluated a fictitious medical condition that was described as either beneficial or detrimental to health and as occurring in either 30% or in one half of 1% of a test population. The condition was evaluated more extremely--as as a more positive health asset or a more negative health liability--in the low-prevalence than in the high-prevalence conditions. Study 2 demonstrated the same effect in self-evaluations and with a different manipulation of perceived prevalence. Ss were told that they actually had the fictitious medical condition, that it was either beneficial or detrimental to their health, and either that they were the only 1 of 5 Ss who had it or that 4 of the 5 did. Low-prevalence Ss exhibited more extreme evaluative, affective, and behavioral reactions to the medical condition than did high-prevalence Ss. The origins and validity of the scarcity principle are discussed, as are its implications for uniqueness theory, reactance theory, and social evaluation theories.     

Social and cognitive strategies for coping with accountability: conformity, complexity, and bolstering

This experiment tested predictions derived from a social contingency model of judgment and choice that identifies 3 distinctive strategies that people rely on in dealing with demands for accountability from important interpersonal or institutional audiences. The model predicts that (a) when people know the views of the audience and are unconstrained by past commitments, they will rely on the low-effort acceptability heuristic and simply shift their views toward those of the prospective audience, (b) when people do not know the views of the audience and are unconstrained by past commitments, they will be motivated to think in relatively flexible, multidimensional ways (preemptive self-criticism), and (c) when people are accountable for positions to which they feel committed, they will devote the majority of their mental effort to justifying those positions (defensive bolstering). The experiment yielded results supportive of these 3 predictions. The study also revealed some evidence of individual differences in social and cognitive strategies for coping with accountability.     

Relation of sympathy and personal distress to prosocial behavior: a multimethod study

Assessed sympathy and personal distress with facial and physiological indexes (heart rate) as well as self-report indexes and examined the relations of these various indexes to prosocial behavior for children and adults in an easy escape condition. Heart rate deceleration during exposure to the needy others was associated with increased willingness to help. In addition, adults' reports of sympathy, as well as facial sadness and concerned attention, were positively related to their intention to assist. For children, there was some indication that report of positive affect and facial distress were negatively related to prosocial intentions and behavior, whereas facial concern was positively related to the indexes of prosocial behavior. These findings are interpreted as providing additional, convergent support for the notion that sympathy and personal distress are differentially related to prosocial behavior.