References Halliday

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Twelve subjects were tested with D-amphetamine, yohimbine, clonidine, and a placebo on a task with two levels of stimulus and two levels of response complexity. The purpose of this study was to test the hypothesis that noradrenergic drugs affect early stimulus processes. D-amphetamine speeded reaction time (RT), clonidine slowed it, and yohimbine had no(More)
We measured performance and event-related brain potential (ERP) map latencies in 12 subjects during four visual discrimination tasks to compare the timing of scopolamine effects on information processing and attention. "Topographic component recognition" found ERP map latencies at times of best fit with a component model map. This "common topography"(More)
Many studies have found that cigarette smoking or nicotine improves mental functioning in abstinent smokers. An unresolved issue is whether this improvement is due primarily to a direct facilitation of performance or to relief of the impairment caused by nicotine withdrawal. We evaluated the performance of 12 non-smokers before and twice (15 and 45 min)(More)
Hyperactivity in children has been attributed to underarousal, maturational lag, and both. Using event-related potentials (ERPs) and EEG spectra, we compared hyperactive children with age-matched normal controls. Neither underarousal nor maturational lag explained our findings, and we concluded that these explanations are now too simple to be useful. We(More)
In a previous study of the effect of age on information processing, both age and stimulus complexity slowed reaction time (RT) and the latency of the P300 component of the brain event-related potential (ERP). The aim of the present study was to compare the effects of scopolamine (an anticholinergic) with the previously noted effects of age. The choice of(More)
Models of information processing currently popular in cognitive psychology divide the reaction process into a series of discrete separable stages. The distinction between one stage and another is verified by the additive factors method (AFM) as defined by Sternberg (1969). Task factors that do not interact with each other are inferred to affect different(More)
Visual event related potentials (ERP) were recorded from 21 hyperactive children aged 7-13 years under two attention conditions at 4 levels of methylphenidate dose (placebo, low, medium and high). ERP measures were very sensitive to age (under or over 10 years) and attention condition, but less sensitive to drug dose. There appeared to be two classes of(More)
A simple technique for generating averaged evoked potentials to auditory signals that appear to move in space is described. Shifts in the apparent location of the signal were created by digitally delaying the output of a white noise generator with a minicomputer. The two channels were reconverted to two analog signals and presented binaurally through(More)
In humans, close relationships are found between cholinergic activity and constraints placed on information processing operations. This is true for all operations where the effects of cholinergic activity have been studied. Studies of vigilance, memory, problem solving, stimulus processing and response processing are cited as illustrations. These studies(More)