A feature-integration theory of attention

A new hypothesis about the role of focused attention is proposed. The feature-integration theory of attention suggests that attention must be directed serially to each stimulus in a display whenever conjunctions of more than one separable feature are needed to characterize or distinguish the possible objects presented. A number of predictions were tested in a variety of paradigms including visual search, texture segregation, identification and localization, and using both separable dimensions (shape and color) and local elements or parts of figures (lines, curves, etc. in letters) as the features to be integrated into complex wholes. The results were in general consistent with the hypothesis. They offer a new set of criteria for distinguishing separable from integral features and a new rationale for predicting which tasks will show attention limits and which will not.     

The effect of self-recording and social reinforcement components of parent training programs

This investigation attempted to assess the effectiveness of two components of parent training programs: (1) the effect of a self-behavior management project prior to intervention with deviant child behaviors, and (2) that of social reinforcement from peers and the consultant. Four groups of parents were exposed to a basic training program and were measured on their success in an intervention program in the inappropriate behavior of their children (ages 7–9 years). Two groups of parents were requested to do a self-modification program prior to the intervention with deviant child behavior; two groups did a child intervention program without a self-management project. One group in the self-management and one group without self-management received verbal social reinforcement from peers and the consultant during interventions. Results obtained indicate that the parent group whose training involved a self-behavior management project prior to intervention with their child's inappropriate behavior and verbal social reinforcement achieved a significantly greater reduction of these behaviors when compared to the groups where either self-management of social reinforcement was used.     

On the study of statistical intuitions

The study of intuitions and errors in judgment under uncertainty is complicated by several factors: discrepancies between acceptance and application of normative rules; effects of content on the application of rules; Socratic hints that create intuitions while testing them; demand characteristics of within-subject experiments; subjects' interpretations of experimental messages according to standard conversational rules. The positive analysis of a judgmental error in terms of heuristics may be supplemented by a negative analysis, which seeks to explain why the correct rule is not intuitively compelling. A negative analysis of non-regressive prediction is outlined.     

Illusory conjunctions in the perception of objects

In perceiving objects we may synthesize conjunctions of separable features by directing attention serially to each item in turn (A. Treisman and G. Gelade, Cognitive Psychology, 1980, 12, 97–136). This feature-integration theory predicts that when attention is diverted or overloaded, features may be wrongly recombined, giving rise to “illusory conjunctions.” The present paper confirms that illusory conjunctions are frequently experienced among unattended stimuli varying in color and shape, and that they occur also with size and solidity (outlined versus filled-in shapes). They are shown both in verbal recall and in simultaneous and successive matching tasks, making it unlikely that they depend on verbal labeling or on memory failure. They occur as often between stimuli differing on many features as between more similar stimuli, and spatial separation has little effect on their frequency. Each feature seems to be coded as an independent entity and to migrate, when attention is diverted, with few constraints from the other features of its source or destination.     

Cerebral asymmetry in infants.

This paper examines the intercorrelation matrix of the subtests of the Porch Index of Communication Ability using a variety of factor analytic and rotational procedures. In addition to a general factor reflecting overall language dysfunction, verbal, graphic, and gestural factors were also found which accounted for 83% of the total variance. These factors were related to Schuell's Howes', and Wepman's models of aphasia. The impact of factor analytic methodology on the conclusions drawn from the same data was also examined and suggestions for clinical use of this battery were discussed.     

Empirically derived groups in the assessment of recovery from aphasia.

This paper examines the pretreatment intercorrelation matrix of the subtests of the Porch Index of Communication Ability to derive factors reflecting components of language impairment. In addition to a general factor reflecting overall language dysfunction, five specific factors reflecting verbal competency (fluency), graphic-verbal expression, gestural-verbal expression, gestural-nonverbal comprehension, and graphic-geometric comprehension were found which accounted for 90.6% of the total variance. A cluster analysis of the five pretreatment factor scores yielded six groups which accounted for 79% of the variance for these factors. These groups were differentiated primarily in terms of impairment and showed a high rate of accuracy prediction for group membership (97.5%). These groups were extremely stable, as shown by the 75% accurate prediction rate derived from the post-treatment factor scores. The effectiveness of this model in generating homogeneous and highly discriminable groups based on objective measures of the patient's language functions indicates that classification of patients into empirical groups should be a major concern of any research design. Implications for assessing effectiveness of therapeutic intervention and the design of test battery were also discussed.     

Stimulus control of defensive burying in the rat

Rats shocked once through a wire-wrapped stationary prod mounted on the wall of a test chamber incorporated the bedding material covering the chamber floor into a defensive reaction. When tested 1 min later, they approached the prod and buried it. Evidence was provided by three separate studies of this burying response that rats had learned about the association of both the position and brightness of the prod with shock after this single conditioning trial. In Experiment 1, the amount of burying decreased if either the position or brightness of the prod had been changed prior to the test. In Experiments 2 and 3, rats were shocked through one of two prods (white or black) mounted on opposite walls of the test chamber. When the positions of the prods were unchanged for the test, almost every subject buried the prod through which it had been shocked, even when the conditioning-test interval was 24 hr; whereas, each rat directed substantial amounts of bedding material at both prods when the positions of the two prods were reversed. Thus, discriminated “avoidance” learning can be rapid, reliable, and enduring when shock is administered “by” a clearly defined stimulus object, i.e., when cue and consequence are spatially contiguous.