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Biomedical subjects

K Ball

Publications and source records attributed to K Ball.

At least 145 records · Page 8Linked to original sources
PubMed1980

Human vision favors centrifugal motion.

Reaction times to motion onset were measured for targets in the peripheral field. Horizontal motion away from fixation evoked faster reactions than did motion toward fixation. The difference between motion toward fixation and motion away from fixation (i) increases with stimulus eccentricity, (ii) is not found when motion is along a vertical axis, and (iii) fails to affect contrast thresholds. The anisotropy between centrifugal and centripetal motion is correlated with differences in the apparent speed of targets moving in the two directions.

Female↗
PubMed1979

Children's understanding of monosyllabic nouns in quiet and in noise.

A four-alternative, forced choice adaptive procedure was used to measure the lowest intensity at which children could identify monosyllabic nouns that had been standardized to be understandable (at comfortable listening levels) to inner city, 3-year-old children. Results showed no age-related performance changes when the words were presented against a 12-talker babble or against filtered noise. In quit, however, performance improved between the ages of 5 and 10 years. Performance of children with learning problems was poorer than performance of children achieving normal school progress, even though clinical measures of auditory sensitivity showed no differences. Results are discussed in terms of "semantic closure" skills of children.

Adult↗
PubMed1977

Mental set alters visibility of moving targets.

An observer's knowledge of a moving target's direction and velocity enhances detectability. In addition, knowledge of direction and velocity speeds an observer's reaction to the motion of a previously stationary target. Since rival, nonperceptual hypotheses can be ruled out, these effects represent a direct modulation of vision by mental set.

Cognition↗
PubMed1976

The cardiologist's responsibility for preventing coronary heart disease.

The recent increase in coronary heart disease is real and the causes must mainly be environmental. Consequently the condition should largely be preventable. The application of what is already known is likely to be a far more effective way of reducing the mortality rate than all attempts at palliative treatment, but vigorous action will be necessary. Much greater sums are being expended on coronary-care units and cardiac surgery than in preventing the need for them, although there is little evidence that they have significantly lowered the over-all mortality rate. Conventional treatment is immensely expensive. Prevention could in the long run be much cheaper. Cardiologists on their own are unlikely to succeed in a program of prevention. They need the help of many others, including community nurses, nutritionists, public health workers, sociologists, and of course general practitioners, but they have responsibility for leadership and for providing background knowledge. For the detection of certain risk factors, health examinations are necessary and should be part of general practice. Also, advice is best given on an individual basis. The chief-known risk factors (hyperlipidemia, hypertension, smoking, physical inactivity) could be controlled. CHD occurs in adults but atherosclerosis starts many years before. Prevention should begin with appropriate infant feeding, whenever possible with breast milk, and continue into childhood, when habits are formed and attitudes to life can best be influenced. It should be possible to bring up children virtually free from risk factors. It may never be possible to prove the effectiveness of such a multifactorial program by prospective controlled intervention studies, but the evidence indicates strong probability. The stakes are too high to delay action any longer. Physicians daily give advice in areas where the evidence is much less certain. Such a program for the control of coronary artery disease is urgently needed and could become one of the most rewarding activities for the medical profession.

Adult↗