The effect of abnormal displacement of the retinal image during eye movements

The displacement of the images on the retina that results from a turning of the eye does not lead to an apparent motion of what is seen, It has been generally assumed that this is due to a compensating process which takes eye movement into account and serves to discount those image displacements that result from eye movements, It follows from this view that an abnormal image displacement, that is, an image displacement that is larger or smaller than the causing eye movement would warrant, should lead to an experienced displacement of the target. Abnormal image displacement was produced by placing the eye in the converging or diverging bundle of rays from a point source that form behind a strong positive lens; this arrangement yielded a disc-shaped image, the projection of the pupil onto the retina, which displaced abnormally during eye movements. By changing the position of the eye along the axis of the lens in relation to the crossing point of the bundle, the degree to which the displacement was abnormal could be varied, For various displacement rates ranging from 25% to 120 and 400% of normal, abnormal displacements produced by incidental eye movements remained unnoticed, Only where eye movements were intentional did some of our Ss report shifts of the perceived image. It is suggested that the organism copes with the image displacement resulting from the ever-present incidental eye movements not by compensation but by ignoring them.     

Source variability and recall of auditory material 1

Recall of auditory narrative material was measured under three conditions of presentation. These were a single source condition with material from one speaker, a four source fixed sequence condition with material from four speakers in a fixed sequence of 3-sec. lengths, and a four source random condition with material from four speakers in a random sequence of 3-sec. lengths. Recall was better for the single source condition than for the four source conditions. No significant difference was found between the fixed and random sequential presentations. Results are discussed in terms of the attentional behaviors involved in the tasks.     

Information processing,neuropsychological function,and the inherited predisposition to alcoholism

Sons of male alcoholics are at particularly heightened risk for the development of alcoholism. This heightened risk frequently appears in association with increased incidence of conduct disorder or hyperactivity, with deficits in abstract thinking and poor school performance, with abnormalities in cued psychophysiological response, and with increased sensitivity to the putatively stress-response-dampening effects of alcohol intoxication. This risk and its associated features are discussed within the context of a neuropsychological theory, predicated on the notions (1) that deficits in cognitive functions theoretically dependent upon the intact functioning of the prefrontal cortex could underlie manifestation of the idiosyncracies commonly attributed to sons of male alcoholics, and (2) that acute alcohol intoxication could relieve the subjective discomfort associated with the consequences of such deficits.     

BIOLOGY AND THE SOCIAL SCIENCES

Abstract. The sciences may be conceptualized as a hierarchy ranked by level of organization (e.g., many-body physics ranks above particle physics). Each science serves as an antidiscipline for the science above it; that is, between each pair, tense but creative interplay is inevitable. Biology has advanced through such tension between its subdisciplines and now can serve as an antidiscipline for the social sciences—for anthropology, for example, by examining the connection between cultural and biological evolution; for psychology, by addressing the nature of learning and the structure of the unconscious; for economics, by examining economically irrational behavior and by comparing economic activity in humans and other species. Sociology, concerned mainly with advanced literate societies, is relatively remote from the genetic basis of human social behavior. However, moving between biological and social levels of organization generates richness and points to new and unexpected principles.     

Near-death experiences and the measurement of blood gases

Although cerebral anoxia is not thought to be responsible for triggering near-death experiences (NDEs), the issue is not so clear in the case of hypercapnia. Detection of normal blood gases in Michael Sabom's (1982) case study seems to be the major reply to suggestions that hypercapnia may have a causal role in NDEs. We argue, however, that routine arterial measures of blood gases are not a reliable indicator of cerebral levels.     

Connecting the Commodore 64 to the IBM PC

Hardware is described that permits bidirectional transfer of data between the Commodore 64 and an IBM-compatible PC. Commercial terminal programs can be used to transmit data. The hardware, which can be constructed for less than $15, opens up several opportunities for making good use of the cost-effective C64 computer.     

Improved standards for laboratory animals?

In February 1993, Judge Charles R. Richey of the United States District Court issued a summary judgment in the case of Animal Legal Defense Fund, et al. v. The Secretary of Agriculture, et al. The decision, which was in favor of the Animal Legal Defense Fund, requires the U.S. Department of Agriculture to withdraw its current regulations governing exercise for dogs and the psychological well-being of nonhuman primates used for biomedical research and to issue new regulations containing only minimum, measurable standards. Both plaintiffs and defendants contended that they were seeking the best interests of the laboratory animals. The issue at stake is whether animals are better protected if the government establishes limited minimal standards or is allowed to require institutions to provide additional standards, which will be judged on the basis of their effectiveness in maintaining healthy animals. The Court avoided this dispute, however, by placing primary emphasis on applying the Administrative Procedures Act and stating that it was merely interpreting the "plain meaning" of the Animal Welfare Act, as amended. In this article, arguments are presented for interpreting the law in a far more flexible way than Judge Richey did. The conclusion is also reached that there were no winners in the Animal Legal Defense Fund case and that the real losers are the laboratory animals.