Inhibition of return is not detected using illusory line motion

Inhibition of return (IOR) is the name that has been assigned to a response time (RT) delay to a stimulus presented at a recently stimulated spatial location. A commonly held explanation for the origins of IOR is that perceptual processing is inhibited and that this inhibition translates into slower RT. Three experiments with 10 subjects were used to directly test this perceptual explanation. The first two experiments assessed the level of perceptual facilitation present in the IOR paradigm using the frequency and latency of illusory line motion judgments. Contrary to the predictions of the perceptual view, the line motion and RT measures revealed only speeded processing at previously stimulated spatial locations. Experiment 3 required a simple detection response and used the same stimulus and timing parameters as those in Experiments 1 and 2. IOR was present, replicating the recent finding that judgments based on perceptual qualities of the stimulus do not demonstrate a RT delay, whereas simple detection tasks do show RT inhibition at previously stimulated locations. These findings are discussed in relation to a number of hypotheses about the origin of the RT delay.     

Average KR degrades parameter learning

In the present study, the effects of average knowledge of results (KR) about a set of trials on the learning of a spatiotemporal movement pattern were examined. Participants (N = 85) practiced 3 movement patterns with the same relative and absolute timing and the same relative amplitudes but with varied absolute amplitudes. Five groups of participants practiced under 1 of the following 5 conditions: KR after every trial (100% KR); average KR after every 3rd trial (average); average KR after every trial about the last 3 trials (running-average); KR after every 3rd trial (33% KR); and KR after every trial; plus average KR after every 3rd trial (both). Although there were no differences between groups in the learning of the fundamental movement pattern (or generalized motor program), average feedback (average, running-average) clearly degraded subjects' ability to learn to properly parameterize the actions in amplitude.     

Book reviews

Pseudo‐Problems. How Analytic Philosophy Gets Done, Roy Sorensen, 1993. London, Routledge xi + 291 pp., hb £37.50, ISBN: 0–415–09464X

Changing Tools: Case Studies in the History of Scientific Methodology, Marta Feher, 1995. Adademiai Kiado £23.17, ISBN: 9630567288

Evolutionary Naturalism, Michael Ruse, 1995, London, Routledge pp. 316, hb £35, ISBN 0–415–08997–2

Knowledge and the Body‐Mind Problem: in Defence of Interaction, Sir Karl Popper, 1994 London, Routledge ix+ 158 pp., hb £25; £10.99 pb, ISBN: 0–415–11504–3

Whys and Ways of Science, Peter J. Riggs, 1992 Melbourne University Press ix + 235 pp., £11.95, ISBN: 0522844715

Rethinking Objectivity, Aixan Megill, Ed., 1994 Durham and London, Duke University Press ix +342pp., £43.50, ISBN: 0822314797

Projective Probability, James Logue, 1995 Clarendon Press xiii+ 171 pp., £24.75, ISBN: 0198239599

Self‐motion: from Aristotle to Newton, M. L. Gill & J. G. Lennox (Eds), 1994 Princeton, New Jersey, Princeton University Press xxi + 367 pp., £36.50, ISBN: 0–691–03235–1     

Social class and sex as determinants of future orientation (time perspective) in adults

This studv was designed to test hypotheses concerning the influence of sex roles and social status on future orientation (FO). The latter was measured in various categories (spheres of life),on the dimensions of density (number of hopes andfears cited by the subject), extension, and optimism-pessimism. Also included was a measure of ‘internal vs. external control’ (the subject's assessment as to whether the realization of his hopes and fears is dependent more on himself or more on external factors). Subjects were 100 employed men and women of the lower and middle class. It was found that, in comparison with women, men voiced more hopes/fears in the public sphere (economy, politics, environment) and fewer in the private sphere uamily, occupation, personal development). Men had a more extended FO in the occupational and economic spheres; women, in contrast, in the private sphere. (These results contradicted the assumption of earlier studies that FO is a general orientation, not varying across different domains of life.) Middle-class (in comparison to lowerclass) persons manifested a, wore extended FO, envisioned the distant future more optimistically, and believed more markedly that the realization of their hopes and fears depended on themselves.     

Effects of group contingent events upon classroom noise

The first study investigated a group control procedure for suppression of excessive sound-intensity levels in a regular public school classroom. Reinforcement consisted of a 2-min addition to the class gym period and a 2-min break after maintenance of an unbroken 10-min quiet period as monitored on a decibel meter. Transgressions of the sound limit (42 decibels) resulted in a delay of reinforcement by the resetting of the timer to the full 10-min interval. The results indicated that these procedures were highly effective in suppression and control of sound intensities. The second experiment utilized a similar procedure coupled with a procedure of eliminating out-of-seat behavior. Experiment III studied the effects of Exp. II procedures on a single student's out-of-seat behavior rate. All procedures were found effective.     

Event-related potential studies of cerebral specialization during reading: I. Studies of normal adults

A number of methodological features were incorporated in a paradigm designed to maximize the likelihood of finding reliable event-related potential (ERP) signs of functional specializations between and within the cerebral hemispheres. Every subject was more accurate in identifying words presented to the right than to the left visual field. The morphology of the ERPs elicited by these words varied considerably as a function of electrode position both within and between the hemispheres. Amplitude asymmetries of ERP components recorded from occipital regions of the two hemispheres varied systematically with the position of the word in the visual field. On the other hand, ERPs from more anterior (temporal and frontal) regions displayed large asymmetries which were in the same direction regardless of the visual field of word presentation. The most prominent such asymmetry was in the negativity in the region 300–500 msec (N410) which was larger in the left than the right hemisphere in every subject. These results demonstrate that in this paradigm which demands specialized language processing ERPs are sensitive to aspects of cerebral organization both within and between the two hemispheres.     

Persuasion,surveillance, and voting behavior

More than 4000 students received one of three letters urging them to vote in a campus primary election. Two letters suggesting that voting behavior would be monitored produced 37% turnout compared with 32% for a nonsurveillance letter and 26% for noletter controls. Differences among these three groups are significant at p < .01. The letters also increased turnout in a runoff election held one week after the primary; however there were no differences among the three letters. These results are discussed in terms of Thibaut and Kelley's three-step process for enforcing group norms.