Support for lateralization of the Whorf effect beyond the realm of color discrimination

Recent work has shown that Whorf effects of language on color discrimination are stronger in the right visual field than in the left. Here we show that this phenomenon is not limited to color: The perception of animal figures (cats and dogs) was more strongly affected by linguistic categories for stimuli presented to the right visual field than those presented to the left. Moreover, the magnitude of the visual field asymmetry was reduced when demands on verbal working memory were increased by a secondary task. This reduction did not occur when the secondary task imposed demands on spatial working memory. Taken together, these results demonstrate that the lateralized Whorf effect may be quite general, reflecting an interaction of linguistic and perceptual codes primarily in the left hemisphere.     

Quantum dynamics of human decision-making

A quantum dynamic model of decision-making is presented, and it is compared with a previously established Markov model. Both the quantum and the Markov models are formulated as random walk decision processes, but the probabilistic principles differ between the two approaches. Quantum dynamics describe the evolution of complex valued probability amplitudes over time, whereas Markov models describe the evolution of real valued probabilities over time. Quantum dynamics generate interference effects, which are not possible with Markov models. An interference effect occurs when the probability of the union of two possible paths is smaller than each individual path alone. The choice probabilities and distribution of choice response time for the quantum model are derived, and the predictions are contrasted with the Markov model.     

The use of the position analysis questionnaire in selecting correlates of job performance among mentally retarded workers

The present study investigated the efficiency of various existing measures, mainly psychological tests, for predicting job performance of mentally retarded workers in a sheltered occupational shop. Twenty-two production-related jobs and one nonproduction-related job were analyzed with the Position Analysis Questionnaire resulting in two job attribute clusters. Correlations between 19 predictor variables and 5 criterion variables, which consisted of supervisor ratings of job performance, were then calculated separately for subjects performing preferred jobs in each attribute group. The results indicated that, contrary to past research, existing measures are predictive of performance on some but not all jobs in a sheltered workshop.     

Visual imagery and verbalization with simple tachistoscopic displays

Two experiments, designed to compare the perception and retention of tachisto-scopic displays of four block capital letters and four simple “nonsense” figures are described. The results show that the letters were much better remembered and suggest that this was mainly due to the ease with which they were verbalized. The nonsense figures usually gave rise either to rapidly fading “iconic” images, or to an unstable kind of mixed imagery which was difficult to describe or remember, but in which inadequate verbalization was often a source of error. Subsidiary experiments illustrate the importance, not only of verbalization, but also of symmetry and simplicity in remembering visual display.     

An experimental and theoretical investigation of the constant-ratio rule and other models of visual letter confusion

The constant-ratio rule (CRR) and four interpretations of R. D. Luce's (In R. D. Luce, R. R. Bush, & E. Galanter (Eds.), Handbook of mathematical psychology (Vol. 1). New York: Wiley, 1963) similarity choice model (SCM) were tested using an alphabetic confusion paradigm. Four stimulus conditions were employed that varied in set size (three, four or five stimulus elements) and set constituency (block letters: A, E, X; F, H, X; A, E, F, H; A, E, F, H, X), and were presented to each subject in independent blocks. The four interpretations of the SCM were generated by constraining one, both, or neither of its similarity and bias parameter sets to be invariant in across-stimulus set model predictions. The strictest interpretation of the SCM (both the similarity and bias parameters constrained), shown to be a special case of the CRR, and the CRR produced nearly equivalent across-set predictions that provided a reasonable first approximation to the data. However, they proved inferior to the least strict SCM (neither the similarity nor bias parameters were constrained; the common interpretation of the SCM in visual confusion). Additionally, the least strict SCM was compared to J. T. Townsend's (Perception and Psychophysics, 1971, 9, 40–50, 449–454) overlap model, the all-or-none model (J. T. Townsend, Journal of Mathematical Psychology, 1978, 18, 25–38), and a modified version of L. H. Nakatani's (Journal of Mathematical Psychology, 1972, 9, 104–127) confusion-choice model. Both the least strict SCM and confusion-choice models produced nearly equivalent within stimulus set predictions that were superior to the overlap and all-or-none within-set predictions. Measurement conditions related to model structure and equivalence relations among the models, many of them new, were examined and compared with the statistical fit results of the investigation.     

A note on the identifiability of parallel and serial processes

Due to the significant research effort devoted to discovering whether certain psychological processes are serial or parallel, it seems important to establish the degree to which such processes are identifiable and to investigate possible ways in which such knowledge can improve our experiments. General definitions of parallel and serial systems are given, followed by a qualitative summary of identifiability results obtained with special classes of exponential systems. Some of these results are applied to a current experimental paradigm, and possible