The semantic deficit hypothesis: Perceptual parsing and object classification by aphasic patients

Many aphasic patients are impaired in their ability to provide or to recognize the names of objects, but little is known about the processing deficits that underlie these difficulties. In this report, a model of object naming/name recognition is proposed, and a prediction is tested concerning one possible functional locus of impairment in name-recognition and object-naming disorders. A subgroup of aphasic patients is found to be impaired in the ability to perform perceptual similarity judgments for pairs of stimulus objects, and to be unable to classify the objects into one of two lexical categories. It is concluded that the classification disorder suffered by these patients results from an impairment at the level of the semantically guided perceptual parsing of objects.     

Attributional styles for helplessness and depression: The importance of sex and situational context

Differences between the sexes in attributions for positive and negative outcomes in either affiliative or achievement situations were examined using the Attributional Style Questionnaire (ASQ). Separate regression analyses for each sex related the ASQ to a measure of helplessness and the Beck Depression Inventory. No differences were noted for attributions to internality or stability; however, females attributed more global causality to positive outcome affiliative situations and negative outcome achievement situations. Regression analyses failed to support the helplessness attributional model of depression. No ratings on the ASQ predicted depression for males; furthermore, for females, only the internal/external dimension was relevant, moderated by both outcome and type of situation. Sex differences were discussed in light of the higher incidence of depression among females.     

Orthographic effects in the word substitutions of aphasic patients: an epidemic of right neglect dyslexia?

Aphasic patients with reading impairments frequently substitute incorrect real words for target words when reading aloud. Many of these word substitutions have substantial orthographic overlap with their targets and are classified as "visual errors" (i.e., sharing 50% of targets' letters in the same relative position). Fifteen chronic aphasic patients read a battery of words and non-words; non-word reading was poor for all patients, and more than 50% of errors on words involved the substitution of a non-target word. An investigation of the factors conditioning these word substitutions, as well as the production of visual errors, identified a number of similarities to patterns previously reported for patients with right neglect dyslexia, which has been said to occur relatively rarely. These included a strong tendency for errors to overlap targets in initial letter positions, maintenance of target length in errors, and the substitution of words higher in imageability than targets. It is proposed that left hemisphere damage frequently leads to disruption of a level of representation for written words in which letter position is ordinally coded, resulting in exacerbation of a normal processing advantage for early letter positions. A computational model is discussed that incorporates this level of representation and successfully simulates relevant normal and patient data.     

Man as a Stabiliser of Systems: From Static Snapshots of Judgement Processes to Dynamic Decision Making

The feedback arrow extending from the response to the distal state in the lens model, together with Brunswik's dictum that the organism is a stabiliser of systems, implies a dynamic view of behaviour. This paper describes the main problems in the study of dynamic decision making: feedback delays and the feedback structure of the tasks. It also describes microworlds, a methodology for studying dynamic decision making in the laboratory. The results from experiments with microworlds show that subjects have problems compensating for feedback delays and side effects. These results are discussed in terms of Brunswik's distinction between perception and thinking.