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Biomedical subjects

W D Hooker

Publications and source records attributed to W D Hooker.

9 recordsLinked to original sources
PubMed1987

Cocaine-calcium channel antagonist interactions.

Diltiazem, a benzothiazepine calcium channel antagonist, was given to six healthy men as a single 60 mg oral dose 120 min before IV injection of cocaine (0.2 mg/kg) in a double-blind, placebo-controlled, two-session study. Diltiazem alone produced no significant effects. Cocaine increased blood pressure, heart rate, pupil size and subjective "high" ratings, and decreased skin temperature. Diltiazem pretreatment diminished the cocaine effect on skin temperature, but did not otherwise alter the response to cocaine. Calcium channel antagonists diminish the effects of cocaine in vitro and in animals. Dosage considerations may be critical because of the differential sensitivity of various tissues to calcium channel antagonists.

Adult↗
PubMed1987

Increased susceptibility to memory intrusions and the Stroop interference effect during acute marijuana intoxication.

The marijuana-induced acute memory impairment was assessed in a double-blind, crossover experiment. Twelve males smoked NIDA-supplied cigarettes containing 1.2% delta-9-tetrahydrocannabinol (THC) or cannabinoid-exhausted marijuana (placebo) in counterbalanced order on 2 days 1-3 weeks apart. Practice, pre- and postsmoking test sessions were conducted with the Paced Auditory Serial Addition Test, Stroop Color and Word Test, and alternate forms of the Randt Memory Battery and the Controlled Oral Word Association Test. A significantly greater number of short story omissions and intrusions occurred in delayed free recall after marijuana. Immediate and sustained attention, controlled retrieval from semantic memory, and speed of reading and naming colors were not affected. The Stroop interference effect was significantly greater following marijuana. Subjects appeared to experience parallel difficulties in inhibiting associations to the new material and inhibiting the overlearned response of reading in a new learning task. Marijuana may compromise associative control, presumably a cognitive process inherent in memory function.

Adult↗
PubMed1987

Cocaine effects on electroencephalographic cognitive event-related potentials and performance.

The effects of cocaine on electroencephalographic indices, information processing and motor performance were measured in 12 normal volunteers. They were tested with an auditory continuous performance task before, 60 and 180 min after a 3 mg/kg oral dose of cocaine hydrochloride or placebo in a double-blind counterbalanced crossover design. EEG from Fz, Cz and Pz were averaged for the eye movement-free correct trials. N100, P200, P300 components and CNV were measured. Cocaine increased N100 amplitude for the warning stimulus and CNV amplitude. P300 amplitude and latency, reaction time and sensory sensitivity (d') were not altered by cocaine. The increase in N100 and CNV amplitude may reflect mobilization of additional attentional resources to produce optimal performance on the task when subjects were distracted by the cardiovascular, subjective and other cocaine effects.

Adult↗
PubMed1986

Neuropsychologic alterations in classic and common migraine.

A neuropsychologic test battery was administered to 16 outpatients with classic migraine and 15 outpatients with common migraine between attacks and 15 matched nonheadache volunteers. Both migraine groups demonstrated significantly greater average neuropsychologic impairment and more self-reported cognitive difficulties than the nonheadache control group. Current medication use did not explain the relative neuropsychologic impairment. Both classic and common migrainous disorders seem to involve a disturbance of cerebral function beyond the attack itself.

Adult↗
PubMed1986

Tetrahydrocannabinol content and differences in marijuana smoking behavior.

Changes in smoking behavior in response to a change in marijuana potency were measured in marijuana users. A marijuana cigarette containing 1.2% or 3.9% tetrahydrocannabinol (THC) was smoked on separate days by ten experienced users. Puff volume, duration and number, interpuff interval, inhalation volume and duration were averaged for each cigarette. The high potency cigarettes were smoked with more puffs and longer interpuff intervals, but also with greater inhaled volumes of air, thereby diluting the marijuana smoke.

Adult↗
PubMed1985

Information processing components of the auditory event related potential are reduced by cocaine.

The effects of cocaine on a human electroencephalographic event related potential (ERP) were measured. Forty-eight subjects received one of three IV doses (0.2, 0.4, or 0.6 mg/kg) and placebo. Thirty-three subjects received one of three oral doses (2, 3, or 4 mg/kg). All IV and oral doses reduced amplitude of the auditory ERP P200 and P300 components during the oddball task. P200 latency decreased. N100 amplitude was reduced only after IV administration. The changes in ERPs occurred during the period of peak cardiovascular and subjective effects. The amplitude reduction in ERP components occurring before the P300 component is consistent with decrements in attention, specifically selective attention. The P300 amplitude reduction after cocaine suggests a disruption of stimulus evaluation resources. The findings are inconsistent with the notion that stimulants affect only response selection and execution. The degree to which stimulants alter cognitive processes prior to response selection may depend on the magnitude of the cardiovascular, subjective, and probably other noncognitive effects.

Administration, Oral↗
PubMed1985

Cocaine increases EEG beta: a replication and extension of Hans Berger's historic experiments.

The effects of cocaine by two routes of administration were studied on the resting, awake human EEG during a 2 min sequential subtraction task. Fifty subjects were given 1 of 3 intravenous cocaine doses (0.2, 0.4 and 0.6 mg/kg). Thirty-three subjects received 1 of 3 oral doses of cocaine (2, 3 and 4 mg/kg). The EEG was analyzed as spectral power for delta, theta, alpha and beta bands. At each dose for both routes of administration, cocaine increased beta power. The increase was observed at the 5 min post-drug test session for the subjects given intravenous cocaine and at both 45 and 75 min test sessions for subjects given oral doses. In addition, a decrease in delta power was found at the 5 min test for the intravenous group and theta power was decreased at the 45 min test session. The increase in beta power was correlated with the area under the cocaine plasma versus time curve, but not with the cardiovascular effects of cocaine. The increased beta activity observed with cocaine may be a consequence of the direct stimulation of a central noradrenergic arousal system.

Adult↗
PubMedDate not supplied

Psychological testing in the workplace.

Describing psychological testing as a controlled observation of human mental functioning through behavior, this chapter examines the variety, settings, and advantages and limitations of psychological tests commonly used in the work setting. Types of tests considered include achievement tests, aptitude tests, and personality and psychological functioning assessments.

Humans↗