Personality, reinforcement and learning.

Conflict in predictions resulting from Eysenck's (1957) and Gray's (1970) theoretical formulations on personality and conditioning were tested at the behavioral level. Given conditions which do not produce over-arousal, it would be predicted from Eysenck's position that Introverts would condition better than Extraverts. From Gray's formulation it would follow that Introverts condition better if negative reinforcement is used and Extraverts condition better if positive reinforcement is used. The two opposing predictions were tested in pursuit rotor learning by either positively or negatively reinforcing the hit/miss dimension of performance by 166 males aged 14 to 15 yr. The results gave support to Gray's position but if over-arousal is assumed Eysenck's position is tenable.     

Picture memory: role of figure-ground organization.

Alterations to the figure of pictures committed to visual memory are more easily detected than alterations to the ground, both in single and paired stimulus tests. Data for 40 scenes from 54 undergraduates suggest that perceptual processes interact with information storage and/or retrieval.     

Control of echolalic speech in psychotic children

Immediate echolalia, a common language disorder in psychotic children, was studied in a series of replicated single-subject designs across six schizophrenic and five normal children. In Experiment 1, each child was presented with several questions and commands, some of which set the occasion for specific, appropriate responses and some of which did not. The former were referred to as discriminative stimuli and the latter, as neutral stimuli. The psychotic children tended to echo the neutral stimuli while responding appropriately to the discriminative stimuli; the normal children, in contrast, typically echoed neither type of stimulus. In Experiment 2, three psychotic children were taught appropriate responses to each of several neutral stimuli. Following this training, the children generally responded appropriately to these stimuli without echoing. A plausible interpretation of these results is that the neutral stimuli were initially incomprehensible or meaningless to the children (whereas the discriminative stimuli were comprehensible or meaningful) and that verbal incomprehensibility may be one important determinant of immediate echolalia. Finally, the results are noteworthy in that they isolate a sufficient treatment variable (i.e., the reinforcement of alternative, nonecholalic responses) for eliminating instances of this language anomaly.     

The effect of a teacher's presence on the classroom behavior of conduct-problem children

Six institutionalized conduct-problem children performed in a classroom under three reinforcement conditions: (1) noncontingent reinforcement: (2) reinforcement for being on task and (3) reinforcement for the accuracy and rate fo their academic behavior. Within each of these conditions, the teacher was either present throughout the class session or absent for a portion of the session. In the teacher's absence, on-task behavior was markedly reduced and disruption was markedly increased, regardless of the reinforcement condition in operation. In contrast, the teacher's absence had no effect on academic accuracy and had a major effect on academic rate only when reinforcement was delivered noncontingently. Furthermore, the extent to which the children became disruptive in the teacher's absence was reduced when reinforcement was contingent upon academic accuracy and rate, instead of being contingent upon being on task or delivered noncontingently. It is suggested that the reinforcement of academic behavior, rather than on-task behavior or classroom social behavior, not only will improve the latter behaviors as well, but possibly also make them less dependent upon the presence and continued surveillance of the teacher.     

The selective impairment of semantic memory

The selective impairment of semantic memory is described in three patients with diffuse cerebrallesions. These patients, selected on the basis of a failure to recognize or identify common objects (agnosia for objects), were investigated in detail. In particular, their perceptual, language and memory functions were assessed, and the limits and properties of their recognition difficulties explored.

It was found that knowledge of pictorial representations of objects, and of words, was impaired or impoverished, and in both instances knowledge of subordinate categories was more vulnerable than superordinate categories. Evidence is presented that this impairment of semantic memory cannot be accounted for by intellectual impairment, sensory or perceptual deficits, or expressive language disorder. The implications of damage to the semantic memory system for the operation of other cognitive systems, in particular short and long-term memory functions, are considered. Some tentative evidence for the structural basis for a hierarchically organized modality-specific semantic memory system is discussed.     

Thalamic modulation of aggression

Integrative Psychological and Behavioral Science - This experiment extends Pavlov’s method of contrasts for 8 components of aggression were quantitatively evaluated in 11 freely moving adult...     

Effect of shifts in body weight on rats' straight alley performance as a function of reward magnitude

The performance of rats trained in a straight alley for 55 trials under 75% body weight and then shifted to 90% body weight was compared to that of rats trained only under 90% body weight. When training was with a small reward the speed of the shifted group decreased to the level of the 90% small reward control groups, but when training was with a large reward the speed of the shifted group dropped below the level of the 90% large reward control group. Thus, the effects on performance of shifting deprivation level following extended training depend on the reward magnitude employed.