Spiral aftereffect duration as a correlate of impulsiveness

In a correlational analysis impulsiveness (Imp), assessed by means of a questionnaire concerned with speed of judgment and decision making, was found to be negatively related to spiral aftereffect (SAE) duration. However, this relationship was present only in a sample of subjects with high neuroticism scores. In this group SAE duration was also positively related to debilitating anxiety. A parallel was seen between Imp and Heymans' “Secondary function,” a personality dimension which was similarly operationalized in a visual aftereffect experiment. Some other SAE correlates are also discussed.     

Spiral aftereffect durations following awakening from REM sleep and non-REM sleep

Nine Ss were awakened 2 min after the beginning of a REM period and 2 min after the beginning of a non-REM period (Stage 4), and were tested on a spiral aftereffect. The duration of the spiral aftereffect was found to be longer for the tests made following REM periods than for the tests made following non-REM periods. The results were interpreted to suggest a possible “carry over” effect from the particular sleep, stage into the waking state.     

Clinical and statistical approaches to the assessment of brain damage in children

In an attempt at innovation in the clinical versus statistical prediction controversy, the present research examined three methods of assessing organic brain damage in a sample of sixty-eight 9- to 14-year-old children. Methods compared were clinical judgment (CP); existing actuarial norms (EAN); and derived statistical prediction (DSP), based on three psychological tests. The results were as follows: (a) None of the methods classified subjects significantly better than chance (p<.05); (b) there was no significant difference (p<.05) among the methods in terms of their rates of accurate classification; (c) CP based on combined tests did not result in higher predictive accuracy than those based on an individual test; (d) CP made after receiving feedback on accuracy showed an increase in number of correct classifications over prior CP; and (e) CP based on knowledge of the statistical prediction in addition to test data showed a higher rate of correct classification than DSP alone.     

Stuttering following brain damage

This paper describes the neurological, language, and speech status of seven brain-damaged patients with symptoms of cortical stuttering. We compare data from our seven patients to data presented on other brain-damaged stutterers, review theories of cortical stuttering's etiology, advance alternative hypotheses about mechanisms underlying such dy sfluencies, and compare cortical stuttering to stuttering in childhood.     

Cluttering after brain damage

On the basis of published cases and of observations made in two patients, a syndrome of acquired cluttering after brain damage in adults is delineated, and a hypothesis is presented regarding the patho-physiology of the disorder.     

Brightness selectivity in the motion aftereffect

Eighteen Ss were required to track the apparent motion of a stationary grating viewed after prolonged inspection of a moving grating. Measures were obtained with the inspection and test gratings identical in contrast but different in space-average luminance, or with luminance held constant and contrast varied. The aftereffect was reduced as the gratings differed in space-average luminance, but contrast exerted less uniform influence as a variable. Brightness-selectivity in the motion aftereffect is interpreted within the selective adaptation model of aftereffects as evidence that some detectors in human vision are conjointly tuned to space-average luminance and image motion.     

An aftereffect in judgment of auditory duration

Two experiments were designed to investigate the occurrence of atemporal aftereffect following auditory spatial stimulation. The task required Ss to compare by means of a motorresponse the duration of a test tone presented at a variable interval after stimulation with a standard tone. In both experiments the posttest duration was underestimated relative to the pretest duration, i.e., there was a temporal aftereffect(TAE). A control experiment which involved Ss making estimates of the duration of the test tones, without the presentation of interpolated standard tones, did not show this effect. The temporal aftereffect followed a function analogous to the “distance paradox” forspatial aftereffects.     

Memory strategies with brain damage

The ability of anterograde amnesics with and without a history of alcoholism and patients with frontal lobe damage to think about memory, memorizing, and remembering was assessed. Alcoholic Korsakoffs' and frontal lobe patients' knowledge and use of memory strategies was deficient when compared with controls whereas nonalcoholic amnesics' was not. The use of the categorization mnemonic was assessed in a verbal learning experiment. Frontal lobe patients failed to spontaneously categorize a categorizable word list when trying to memorize it. Nevertheless, when forced to categorize the list, they benefited from the imposed structure. Nonalcoholic amnesics spontaneously categorized the list and benefited from the resulting organization.