A Psychoneuroimmunologic Perspective on AIDS Research: Questions,Preliminary Findings,and Suggestions1

Starting with the premise that research questions emanating from the fields of psychoneuroimmunology and behavioral medicine may provide critical information for understanding and treating acquired immune deficiency syndrome (AIDS), we provide brief backgrounds on psychoneuroimmunology and on AIDS. Previously, Solomon had generated 25 hypotheses based on the thesis that the immune and central nervous systems are intimately linked. Eight hypotheses from his list are presented as particularly relevant to AIDS. From these hypotheses, we derived a set of 12 new questions to be addressed in research on AIDS. Evidence and illustrations from studies in the literature, from our own research on psychoimmunologic relationships and psychosocial factors related to outcome, and from clinical examples is discussed for each question. Finally, suggestions are offered to address some of the problems in conducting psychoneurologic research.     

Ebbinghaus illusions: Size contrast or contour interaction phenomena?

Forty-eight graduate and undergraduate students between 17 and 30 years of age judged the size of the central circle in Ebbinghaus figures presented under either simultaneous or successive viewing conditions. Successive presentation eliminated the illusion produced by the normally overestimated figure and diminished that produced by the underestimated figure. Under simultaneous viewing conditions, increasing the number of surrounding circles reduced the magnitude of the reversed illusion produced by the normally overestimated figure but had no effect on the illusion produced by the underestimated figure. Under successive viewing conditions, increasing the number of surrounding circles had no effect on the magnitude of illusion produced by the normally overestimated figure but increased the illusion produced by the underestimated figure. These data were interpreted as inconsistent with a size contrast explanation of the Ebbinghaus illusions and suggested that these illusions may be produced by a contour interaction process.     

Directional errors of movement and their correction in a discrete tracking task

Many studies have shown that subjects can correct their own errors of movement more quickly than they can react to external stimuli. In the control of movements, three general categories of feedback have been defined as follows: (a) knowledge of results, primarily visually mediated, (b) proprioceptive or kinesthetic, such as from muscle spindles and joint receptors, and (c) corollary discharge or efference copy within the central nervous system. Experiments were conducted on eight normal human subjects to study the effects of these feedbacks on simple RT, choice RT, and error correction time. The movement used was plantarflexion and dorsiflexion of the ankle joint. The feedback loops were modified (a) by inverting the visual display to alter the subject's perception of results and (b) by applying a 100-Hz vibration simultaneously to both flexor and extensor muscles of the ankle joint. Central processing was altered by giving the subjects moderated doses of alcohol (blood-alcohol concentration levels of up to.10%). Vibration and alcohol increased both simple and choice RT but not the error correction time. These data reinforce the concept that there is a central pathway which can mediate error correcting responses.     

Inward- and Outward-Directed Violence in the Lives of Urban Minority Adults Followed from Middle School into Their Thirties

This study explores connections between inward-directed violence and outward-directed violence using data from the Reach for Health sample, which was originally recruited in the 1990s from three middle schools in economically distressed, predominantly African American neighborhoods of New York City. Now in their thirties, participants (N = 595) completed surveys assessing current suicidal thoughts and behaviors as well as other violence involvements, including intimate partner violence victimization and perpetration. About 10% of males and females reported any suicidal ideation or attempt in the past 12 months. In logistic regression analyses adjusting for sociodemographics, prior reports of feeling blue in middle school (OR: 1.12, CI: 1.02–4.39) and young adult suicidality (OR: 2.54, CI: 1.30–4.95) are significantly related to later suicidality. So are concurrent aggressive behaviors, including reports of physical fighting outside the home (OR: 2.70, CI: 1.29–5.67) and IPV perpetration (OR: 2.09, CI: 1.11–3.94). Neither IPV victimization nor witnessing neighborhood violence is correlated. Findings shed light on the persistence of suicidality in the lives of those who come of age, and often remain, in communities with high levels of poverty, and confirm linkages of suicidality with externally directed aggression. Life-stage interventions are needed to counter the interwoven causes and consequences of multiple forms of violence.     

The Stability Theory of Knowledge and Belief Revision: Comments on Rott

In this commentary on Rotts paper Stability, Strength and Sensitivity: Converting Belief into Knowledge, I discuss two problems of the stability theory of knowledge which are pointed out by Rott. I conclude that these problems offer no reason for rejecting the stability theory, but might be grounds for deviating from the standard AGM account of belief revision which Rott presupposes.