PubMed Health⌕ Search

Biomedical subjects

A W Chau

Publications and source records attributed to A W Chau.

2 recordsLinked to original sources
PubMed1992

Pilot performance with blood alcohol concentrations below 0.04%.

The effects of a low (less than 0.04%) BAC on pilot performance were investigated in a series of four experiments in which pilots flew a light aircraft simulator under alcohol and placebo conditions. The mean BACs of subjects when starting and finishing the test sessions were 0.037% and 0.028%, respectively. Two of the experiments involved demanding flight tasks under instrument meteorological conditions: complicated departure, holding, and approach procedures in one case; and VOR-use intersection problems in the other. The other two experiments involved ILS approaches under turbulence, cross wind, and simulated wind shear conditions that imposed heavy control-task loads on the pilots. Significant alcohol effects were found, but only under the heaviest workload conditions. During posttest interviews 75% of the pilots reported physical and/or mental effects due to alcohol.

Adult↗
PubMed1989

Visuo-spatial processing in parkinsonians.

It has been suggested that patients with Parkinson's disease (PDs) may have problems processing visuo-spatial information and that this deficiency may contribute to the motor control problems observed in PD. However, most studies reporting visuo-spatial deficits are equivocal; they confound perceptual and motor processes. To address this issue, the present experiment systematically compared the relative contributions of several cognitive processes to performance: perception, stimulus-response translation, movement preparation and execution. Seven non-demented PDs and seven age-matched controls performed visual RT tasks, based upon judgements of spatial displacements. Both the RT and MT data suggested that PDs do not prepare movements as adequately as normals, and that PD deficits are associated with problems controlling movement execution. On the other hand, PDs were not slower in judging distances and linking perception to action, suggesting that previous findings of visuo-spatial deficits may be due in part to motor impairments.

Aged↗