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J H Flowers

Publications and source records attributed to J H Flowers.

6 recordsLinked to original sources
PubMed1990

Priming effects in perceptual classification.

Priming stimuli that spatially flank a fixated target stimulus may cause either facilitation or interference with target classification, depending on experimental context. Two experiments demonstrated distinct effects of response compatibility and semantic congruity between flankers and target. Response competition occurred when targets were flanked by context stimuli associated with the opposite response, but this effect diminished when the target was delayed relative to the flankers. Facilitative priming by response-compatible flankers, in contrast, required prior exposure of the flankers, and was strongly influenced by the semantic congruity of flankers and targets. These differing time courses suggest that perceptual priming encompasses a variety of distinct underlying cognitive and motor events.

Attention↗
PubMed1984

Automatic and expectancy-based priming effects in a digit naming task.

In a voice reaction time task, subjects named target digits that were horizontally flanked by noise digits or by a neutral symbol (#). For the control subjects, the noise digits were uncorrelated with the target digit, whereas for three experimental groups, the value of the noise digit predicted the target digit by an arithmetic rule (target = noise, target = noise + 1, target = noise - 1) on 75% of the trials. Patterns of reaction time facilitation and inhibition relative to the control condition among the four subject groups illustrated differing time courses of involuntary and expectancy-based priming. For prediction rules requiring an arithmetic transformation (expect N = 1 and expect N - 1), responses to predicted targets were slowed by response competition at short stimulus-onset asynchrony (SOAs) but greatly facilitated by expectancy at longer SOAs.

Adult↗
PubMed1981

Familiarity, redundancy, and the spatial control of visual attention.

Highly familiar letter sequences (English words) in noncued portions of a tachistoscopic display were shown to substantially reduce accuracy of partial report. These findings suggest that in addition to facilitating character scanning, familiarity may operate in automatically directing attentional resources to a particular spatial region of a display. Such attentional capture may be disruptive if the material to be reported is presented at another location.

Attention↗
PubMedDate not supplied

Microcomputer-assisted open field measures of rats given ethanol on postnatal days 1-8.

This study examined direct effects of postnatally administered ethanol upon growth and adult open field behaviors in male rats. Charles Rivers CD albino rats (13 litters) were used in 5 groups; ethanol, Sustagen, pair-fed, handled, or unhandled. Experimental animals were intragastrically fed ethanol (Sustagen [Mead Johnson] vehicle) twice daily, comparable volumes isocaloric Sustagen, handled or left unhandled. Ethanol doses on postnatal days 1-8, respectively, were: 1, 2, 3, 4, 4, 3, 2, 1 g/kg. Ethanol-pups ceased weight gains at 4 g/kg; a handled pup, kept with a nonlactating female until its body weight matched its ethanol littermate, became a pair-fed control. Group body weights did not differ from day 21 throughout the experiment, day 154. Open field testing (day 120-124) used microcomputer programs to record event times and frequencies. Ethanol-treated rats had lower activity and longer start latencies (p less than 0.05) but did not differ on other computer-timed measures. Unhandled animals displayed some differences. When underfeeding effects are eliminated, ethanol (up to 4 g/kg) given on postnatal days 1-8 produced open field activity changes that persisted until day 120.

Animals↗