Malcolm D. Arnoult

Schematic concept formation: Demonstration in a free sorting task

Presented with a set of patterns containing two schema-defined categories, Ss were asked to sort the patterns into two categories. No instructions about relevant attributes were given, and no feedback was provided. A significant number of Ss used the schema-defined categories in sorting.

Novelty as a determinant of spontaneous alternation in children

Nursery school children traced a series of T-mazes under varying and nonvarying stimulus conditions in a situation arranged such that all external stimulus cues could be apprehended by Ss throughout the entire task. The results of the experiment were interpreted on the basis of Berlyne’s (1960) novelty hypothesis, and it was concluded that spontaneous alternation appeared to be related to the activating properties of novel stimuli.

Magnitude estimation of perceived distance over various distance ranges

Three groups of Os made magnitude estimation judgments of the apparent distance of a stationary space vehicle model under conditions simulating outer space. Psychophysical functions for three stimulus ranges were obtained. The exponents for the near and far stimulus ranges were 1.0. The power function exponent for the “full” range group was 0.48. The psychophysical scales were compared to JND scales obtained in previous research. The results indicated that in all ranges investigated the power law is an appropriate description of the relationship between perceived and objective distance, but that distance range and the location of the range are important determinants of the psychophysical scale.

A comparison of simple correction and functional feedback in schema learning

The role of knowledge of results (KR) in a schematic concept formation task was clarified by manipulating the specificity of information provided during feedback. Ss learned to discriminate between pairs of random forms from two schema families. Verbal correction was compared with a functional KR procedure in which the schema prototypes were superimposed over test stimuli. In no case did verbal correction improve learning in comparison with functional KR. Differences in acquisition persisted in a retention test.

Distance discrimination in a simulated space environment

The just noticeable difference (JND) for distance was investigated by a paired-comparisons method using successive comparisons. The research utilized an optically simulated large target located in a textureless environment at distances along the saggital plane out to 12, 800 ft. The value of ΔD/D varied from less than 3% at 200 ft to about 7% at 12, 800 ft. The results confirmed a power function relationship between distance threshold and observation distance.

ANNOYINGNESS OF AIRCRAFT NOISE IN RELATION TO COGNITIVE ACTIVITY

College students were exposed by means of headphones to two kinds of aircraft noise (helicopter and jet) at three levels of loudness (60, 70, and 80 dB) while engaging in two tests of intelligibility and 12 cognitive tasks. In addition, the annoyingness of the noise was rated on a seven-point scale for each source/loudness combination in each task. Individual-differences measures (embedded figures, locus-of-control, and test anxiety) were also obtained. No performance difference related to noise was obtained in any of the cognitive tasks, and using the individual-difference measures as co-variates made no difference. In a second experiment a limited set of five modified cognitive tasks was used, again without producing any significant results. Finally, a third experiment utilized four cognitive tasks, a perceptual-motor task (Rotary Tracking) and intermittent rather than continuous noise, and yielded the same results. It was concluded that the failure to find performance differences on the cognitive tasks was probably due to the fact that concern for the welfare of the subjects limited the stimuli to loudness levels that were too low to be effective.

Effects of simulated helicopter cabin noise on intelligibility and annoyance

Helicopter cabin noise was simulated by combining a broadband signal (pink noise, or PN) with a triad of pure tones (PT) at 650,1900, and 5000 Hz. Each component was presented at four loudness levels (0,60,70, and 80 dB[A]), with all 16 combinations arranged in two unsystematic orders. Intelligibility was measured by means of sentences to be judged as true or false. A male speaker presented 10 sentences at each noise condition. One group of subjects heard the sentences at 50 dB(A) and another group at 55 dB(A). The annoyance of each noise combination was rated by the same subjects on a 5-point scale. Both sources and their interaction were significantly related to reduced intelligibility and increased annoyance at both speech levels. In general, the PN component was more responsible for loss of intelligibility, and the PT component more responsible for annoyance.