Biomedical subjects

L M van Veggel

Publications and source records attributed to L M van Veggel.

6 recordsLinked to original sources

PubMed1996

Effects of mefloquine alone and with alcohol on psychomotor and driving performance.

OBJECTIVE: To determine whether mefloquine, a quinoline antimalarial drug, affects psychomotor and actual driving performance when given in prophylactic regimen, alone or in combination with alcohol. METHODS: Forty male and female volunteers were randomly assigned in equal numbers to two groups, and were treated double-blind for one month with mefloquine and placebo. The medication was taken in a 250 mg dose on the evenings of Days 1, 2, 3, 8, 15, 22 and 29. Testing was done on Days 4, 23 and 30, the latter after repeated doses of alcohol sufficient to sustain a blood concentration of about 0.35 mg.ml-1. Two real driving tests were used to measure prolonged (1 h) road tracking and car following performance. Critical Flicker/Fusion Frequency (CFF), critical instability tracking and body sway were also measured in the laboratory. RESULTS: Mefloquine caused no significant impairment in any test at any time relative to placebo. It significantly improved road tracking performance on Day 4. A significant interaction between prior treatment and alcohol was found in the body sway test, as the alcohol-induced change was less after mefloquine than placebo. The sensitivity of the driving test and the CFF test were shown by the significant overall effect of alcohol which did not discriminate between the two prior treatments. CONCLUSION: Mefloquine did not impair driving performance but rather improved it in the longer test, suggesting that the drug may possess psychostimulating properties.

Adult↗

PubMed1996

Effects of semprex-D and diphenhydramine on learning in young adults with seasonal allergic rhinitis.

OBJECTIVES: The purpose of this study was to test the hypothesis that learning ability is impaired in patients with seasonal allergic rhinitis relative to untreated individuals and to evaluate a combination compound (acrivastine 8 mg + pseudoephedrine 60 mg) for attenuation of the learning impairment in these patients. BACKGROUND: In a previous study employing the same method it was shown that young children (10 to 12 yrs) suffering from seasonal allergic rhinitis performed significantly worse on tests of learning and using knowledge after acute treatment with a sedating antihistamine (diphenhydramine 50 mg) or placebo as compared with nontreated healthy controls. This effect was partially reversed by treatment with loratadine. METHODS: Sixty-seven young adults suffering from seasonal allergic rhinitis and 28 matched controls were trained on didactic simulation for three consecutive days. Atopic subjects were treated differentially during training according to a double-blind, randomized, parallel group design with either diphenhydramine hydrochloride 50 mg, a combination compound (acrivastine 8 mg + pseudoephedrine 60 mg, A + P), or placebo, administered qd. After training, all atopic subjects were maintained on A + P treatment for 14 days at which time all groups returned for examination. RESULTS: Mean performance at the end of training was worse for all atopic subjects combined compared with normal subjects. Subjects treated with diphenhydramine performed significantly worse than either normals (P < .001) or those treated with A + P (P < .001). At the examination, the diphenhydramine group's performance differed significantly from those of the normal (P < .001) and A + P groups (P < .001). CONCLUSION: The study supports our previous finding that allergy symptoms reduce learning ability which is further reduced learning ability which is further reduced by diphenhydramine. Atopic subjects with allergies treated with acrivastine + pseudoephedrine learned as well as normal subjects.

Adolescent↗

PubMed1995

Anxiolytics' effects on the actual driving performance of patients and healthy volunteers in a standardized test. An integration of three studies.

Effects of benzodiazepine (diazepam, lorazepam) and benzodiazepine-like anxiolytics (alpidem, suriclone) and a 5-HT-3 antagonist (ondansetron) on actual driving performance were measured in three double-blind, placebo-controlled studies. Subjects were healthy volunteers in two and anxious patients in the third. Treatments lasted for 8 days. Standardized testing occurred within the first full day and on the last day of treatment. No important differences existed between volunteers' and patients' baseline and/or placebo performances and both groups responded similarly to comparable drugs/doses. Benzodiazepine and benzodiazepine-like anxiolytics produced marked and pervasive driving impairment, which lasted throughout treatment; but ondansetron, none.

Anti-Anxiety Agents↗

PubMed1994

A cross-study comparison of the effects of moclobemide and brofaromine on actual driving performance and estimated sleep.

Results from two separate studies were combined to compare the acute and subchronic effects of two monoamine oxidase-A (MAO-A) inhibitors, moclobemide and brofaromine, on actual driving performance and sleep. Both studies were conducted according to a double-blind, crossover design involving 18 patients receiving moclobemide and 16 patients receiving brofaromine. Patients were administered either moclobemide 200 mg b.i.d., mianserin 10 mg. t.i.d., and placebo (study 1), or brofaromine 50 and 75 mg b.i.d., doxepin 25 mg t.i.d., and placebo (study 2) for 8 consecutive days. A standardized driving test was conducted on day 1 and day 8 of treatment. Daily logs of estimated sleep duration and quality were obtained. Neither moclobemide nor brofaromine impaired driving performance. Some indication, although statistically not significant, was found that moclobemide improved driving performance on day 1. Brofaromine 75 mg significantly improved driving performance on day 8 of treatment. No significant difference between the effects of both drugs was found in a cross-study comparison. Moclobemide did not affect any sleep parameter, whereas brofaromine shortened sleep duration and decreased sleep quality. On day 1, mianserin and doxepin impaired driving. Impairment dissipated after 8 days of treatment with doxepine but not during treatment with mianserin. Sleep duration was prolonged during treatment with both drugs, whereas sleep quality remained unaffected. It is concluded that both MAO-A inhibitors are safe drugs with respect to driving.

Adult↗

PubMed1993

Seasonal allergic rhinitis and antihistamine effects on children's learning.

Children suffering from seasonal allergic rhinitis and matched normals were instructed on the use of a didactic computer simulation in a realistic classroom situation. Groups of atopic children received different treatments before instruction; ie, sedating (diphenylhydramine HCl) or nonsedating (loratadine) antihistamines or placebo. All returned after 2 weeks for an examination measuring factual and conceptual knowledge and the application of a learned strategy. Examination results showed large and consistent impairing effects of the allergic reaction on prior learning. Both the placebo and diphenhydramine groups learned significantly less than normal controls. The loratadine group's learning performance was superior to either of the other atopic groups' but still inferior to the normals'. Our conclusions are that the allergic reaction reduces learning ability in children and that this effect is partially counteracted by treatment with loratadine and aggravated by diphenhydramine.

Child↗

PubMed1992

Manipulating procedural variables in a spatial precuing task.

Spatial precuing tasks have yielded a consistent pattern of differential reaction time benefits. Specifically, precuing of two fingers on the same hand has been shown to result in faster discrete finger responses than precuing of two fingers on different hands. This phenomenon is called the hand advantage. Within the context of the spatial precuing task originally developed by Miller (1982), a series of four experiments investigated the influences of two procedural variables on the hand advantage: preparation instruction and presentation mode of preparation intervals. Two preparation instruction conditions were compared: implicit versus explicit instructions regarding preparation possibilities. Also, two presentation modes of preparation intervals were studied: a random condition, in which the preparation intervals varied randomly, and a blocked condition, in which the preparation intervals were grouped together in blocks of trials. Results showed that these two procedural variables, when manipulated independently, did not affect the hand advantage. However, when combined, they significantly reduced the hand advantage by half. Moreover, both procedural variables were shown to produce a precuing benefit for two homologous fingers on different hands. We concluded that, in spatial precuing tasks, procedural variables play an important role by inducing preparation strategies, which affect the pattern of reaction time benefits.

Choice Behavior↗