Structural analysis of the intension and extension of semantic concepts

The present studies examined the nature of visuo-spatial working memory development using conventional visual span and spatial span measures. Children aged between 6 and 13 years and adults aged 18-38 years were employed as participants. In Study 1, visual span, spatial span, articulation rate, and verbal fluency competencies were measured. In Study 2, visual span and spatial span maintenance was subject to five interference formats: nil, speech articulation, verbal fluency, visual masking, and spatial tapping. Distinct developmental rates were found for the two span tasks, which in the older children were correlated with the verbal fluency measure. Study 2 provided experimental evidence of the contribution of executive and spatial processes to spatial and to visual span maintenance. The results are interpreted as indicating that these memory span procedures make complex demands upon the visuo-spatial working memory architecture and consequently a precise identification of the process that actually develop is compromised. It is suggested that a componential approach where tasks are constructed to tap specific working memory components would afford a more accurate understanding of the development of these processes.     

A neural autopilot theory of habit: Evidence from consumer purchases and social media use

This article applies a two-process “neural autopilot” model to field data. The autopilot model hypothesizes that habitual choice occurs when the reward from a behavior has low numerical “doubt” (i.e., reward prediction errors are small). The model toggles between repeating a previous choice (habit) when doubt is low and making a goal-directed choice when doubt is high. The model has ingredients established in animal learning and cognitive neuroscience and is simple enough to make nonobvious predictions. In two empirical applications, we fit the model to field data on purchases of canned tuna and posting on the Chinese social media site Weibo. This style of modeling is called “structural” because there is a theoretical model of how different variables influence choices by agents (the “structure”), which tightly restricts how hidden variables lead to observed choices. There is empirical support for the model, more strongly for tuna purchases than for Weibo posting, relative to a baseline “reduced-form” model in which current choices are correlated with past choices without a mechanistic (structural) explanation. An interesting set of predictions can also be derived about how consumers react to different kinds of changes in prices and qualities of goods (this is called “counterfactual analysis”).     

Paying attention to reading errors in acquired dyslexia

The important role of selective attention in normal reading is illustrated by a relatively rare form of acquired dyslexia known as 'attentional dyslexia'. Theories of the functional deficit underlying this disorder differ as to the locus of the attentional dysfunction. A recent study by Mayall and Humphreys has contributed to this debate by studying letter migration errors in an attentional dyslexic.     

A Challenge to Brink's Metaphysical Egoism

Those who subscribe to aprudential conception of practical reason do not believe that there is a conflict between other-regarding and self-regarding norms as the former are held to be founded on the latter. Moral conduct, they maintain, is always rationally justifiable. The reasons we should fulfil the demands of other-regarding norms are the same as those we have for fulfilling self-regarding norms. David Brink has put forth an interesting and novel account of this approach to practical reason which he calls‘metaphysical egoism’. Metaphysical egoism requires that we modify our pre-theoretical understandings of self-interest on metaphysical grounds. I critically assess Brink’s argument and claim that metaphysical egoism does not adequately function as a motive or guide for action. It is susceptible to many of the same problems which strategic egoism faces. This revised version was published online in July 2006 with corrections to the Cover Date.     

Inter‐racial contact and the own‐race bias for face recognition in South Africa and England

Own‐race bias, where people are more accurate recognizing faces of people from their own race than other races, can lead to misidentification and, in some cases, innocent people being convicted. This bias was explored in South Africa and England, using Black and White participants. People were shown several photographs of Black and White faces and were later asked if they had seen these faces (and several fillers). In addition, participants were given a questionnaire about inter‐racial contact. Cross‐race identification accuracy for Black participants was positively correlated with self‐reported inter‐racial contact. The confidence–accuracy relationship was strongest when making own‐race judgements. Copyright © 2003 John Wiley & Sons, Ltd.     

Training on integrated versus separated Stroop tasks: The progression of interference and facilitation

Two experiments examined the course of interference and facilitation in the Stroop (1935) task during training. Two versions of the task were compared: integrated (e.g., the word RED in the color green) and separated (e.g., green asterisks above the word RED). Stimuli were congruent (RED in red), incongruent (GREEN in red), or neutral (XXX in red). Over 5-day (Experiment 1) and 10-day (Experiment 2) training sessions, facilitation due to congruence was small, stable, and equivalent in both task versions. In contrast, interference declined sharply on the integrated task over Days 1-3, then slowed to parallel the gradual decline on the separated task. Finally, training on the color naming task did not affect a word reading task administered after training. These findings imply that (a) Stroop interference initially reflects two problems—overcoming integration and managing two conflicting information sources; (b) with practice, the larger integration problem is solved relatively quickly, rendering the integrated and separated tasks quite comparable thereafter; and (c) facilitation and interference in the Stroop task may be independent. These results challenge extant theories of the Stroop effect, which do not predict such effects.