Neurosteroids in the Hippocampus: Neuronal Plasticity and Memory

The hippocampus, which is critically involved in learning and memory processes, is known to be a target for the neuromodulatory actions of steroid hormones produced by the adrenal glands and gonads. Much of the work of B.S. McEwen and collaborators has focused on the role of glucocorticosteroids and estrogen in modulating hippocampal plasticity and functions. In addition to hormones derived from the endocrine glands, cells in the hippocampus may be exposed to locally synthesized neurosteroids, including pregnenolone, dehydroepiandrosterone and their sulfated esters as well as progesterone and its reduced metabolites. In contrast to hormones derived from the circulation, neurosteroids have paracrine and/or autocrine activities. In the hippocampus, they have been shown to have trophic effects on neurons and glial cells and to modulate the activity of a variety of neurotransmitter receptors and ion channels, including type A gamma-aminobutyric acid, N-methyl-D-aspartate and sigma receptors and N- and L-type Ca2+ channels. There is accumulating evidence that some neurosteroids, in particular pregnenolone sulfate, have strong influences on learning and memory processes, most likely by regulating neurotransmission in the hippocampus. However, the hippocampus is not the only target for the mnesic effects of neurosteroids. Associated brain regions, the basal nuclei of the forebrain and the amygdaloid complex, are also involved. Some neurosteroids may thus be beneficial for treating age- or disease-related cognitive impairments.     

Ethical issues in cochlear implant surgery: an exploration into disease, disability, and the best interests of the child

This paper examines ethical issues related to medical practices with children and adults who are members of a linguistic and cultural minority known as the DEAF-WORLD. Members of that culture characteristically have hearing parents and are treated by hearing professionals whose values, particularly concerning language, speech, and hearing, are typically quite different from their own. That disparity has long fueled a debate on several ethical issues, most recently the merits of cochlear implant surgery for DEAF children. We explore whether that surgery would be ethical if implants could deliver close to normal hearing for most implanted children, thereby diminishing the ranks of the DEAF-WORLD. The ethical implications of eugenic practices with the DEAF are explored, as are ethical quandaries in parental surrogacy for DEAF children, and their parallels in transracial adoption.     

Lateralized Changes in Regional Cerebral Blood Flow during Performance of Verbal and Facial Recognition Tasks: Correlations with Performance and “Effort”

Functional neuroimaging has been used to investigate neural substrates of mnemonic processes, and cerebral blood flow (CBF) measures have been sensitive to activation with memory tasks. Studies of memory with two-dimensional¹³³Xenon clearance techniques found that word and face recognition tasks produced contralateral CBF changes in mid-temporal cortical regions. This study replicated the activation paradigm, expanding to the three-dimensional resolution of positron emission tomography (PET). Word and face recognition, and a control baseline task were administered to 19 healthy right-handed volunteers (11 men, 8 women) during successive 10 min PET¹⁵O-water measures of CBF. Quantitative CBF rates were calculated with the arterial input function and the equilibrium model. Redistributions of blood flow were compared across tasks using both absolute and relative (region/whole brain) CBF.Replicating the¹³³Xenon clearance findings, CBF was “appropriately” lateralized during task performance (left–right for words > left–right for faces) in the mid-temporal region. Contrary to predictions, the recognition tasks did not activate expected mesolimbic or prefrontal areas. The task-induced CBF changes also correlated with performance. Bilateral CBF in mid-temporal and parahippocampal gyrus regions of interest correlated with the ability to correctly identify word targets (sensitivity). Left-lateralized CBF in the amygdala and hippocampus correlated with better word sensitivity as well as specificity (ability to correctly reject foils). Complementally, right-lateralized CBF in the parahippocampal gyrus correlated with better face specificity performance. In addition, left-lateralized CBF in the amygdala and right-lateralized CBF in the parahippocampal gyrus and hippocampus correlated with “mental effort” indices (task performance relative to basal ability) for word and face memory tasks, respectively. Thus, whereas this recognition task showed the expected lateralized increase in the mid-temporal region and not in frontal and limbic areas, lateralized activation in some of these areas was associated with better performance. Exploratory analyses on other regions showed lateralized changes in one additional temporal region, the occipital-temporal, and several limbic regions.     

The specific action of different personality risk factors on cancer of the breast, cervix, corpus uteri and other types of cancer: A prospective investigation

We report the results of a prospective study of a random sample of 1353 elderly but healthy men and women who were followed up for a period of 10 yr, when mortality and cause of death were ascertained. Overall results have been reported elsewhere for mortality from cancer, coronary heart disease and other causes; here we are concerned with the personality factors predicting breast cancer, cervical cancer, cancer of the corpus uteri specifically, as well as other types of cancer in women. Ten specific hypotheses were tested, using specially constructed questionnaires for the purpose, and for most of these statistically significant support was obtained. The results justify belief that specific types of cancer may be related to specific stress/personality factors.     

Is it emotion or is it stress? Gender stereotypes and the perception of subjective experience

Two studies of college undergraduates (ns = 95 and 92, primarily non-Hispanic whites and Asian Americans) investigated gender stereotypes of stress and emotion, as well as variables that influence the perception of gender-related differences. Study 1 assessed how gender stereotypes differ from the self-reports of men and women. When asked to choose a label for the subjective experience of the average man and the average woman in a series of problematic hypothetical situations, participants generally tended to believe that the average female would feel ‘emotional,” but that the average male would feel “stressed.” By contrast, the label participants chose to describe their own subjective experience was not significantly affected by their gender. In addition, participants believed the average woman and man differed more in the intensity of their emotions than in the intensity of their stress, a belief contradicted by their own self-reports. Results of Study 2 indicated that gender-related differences in estimations of stress and emotion for the self were reduced or eliminated when specific information about experience-eliciting situations was provided. We would like to thank Matthew Dank for his help in preparing the stimulus materials.     

A History of the Extraterrestrial Life Debate

From antiquity to the present, humans have debated whether intelligent life exists elsewhere in the universe. This presentation will survey this debate, examining the roles played in it by science, religion, philosophy, and other areas of human learning. One thesis that will be developed is that whether or not extraterrestrials exist, ideas about them have strongly influenced Western thought.     

Genes and human behavior: the emerging paradigm

The physical properties of human beings and other organisms as well as their social behavioral traits are manifestations of both genetic inheritance and environment. Recent behavioral research has indicated that certain characteristics or behaviors—such as schizophrenia, divorce, and homosexuality—are highly heritable and are not governed exclusively by social environment. A balanced view of human behavior includes the effects of social learning as well as of genetically determined behavior. A new paradigm promotes enhanced understanding and acceptance of human diversity, be it cultural, racial, or sexual, and has the potential to unite scientists and theologians by creating common grounds of understanding.     

Sexuality education and young people's sexual behavior: a review of studies

Sexuality education for children and young adults is one of the most heavily debated issues facing policy-makers, national AIDS program planners, and educators, provoking arguments over how explicit education materials should be, how much of it there should be, how often it should be given, and at what age instruction should commence. In this context, the World Health Organization's Global Program on AIDS' Office of Intervention Development and Support commissioned a comprehensive literature review to assess the effects of HIV/AIDS and sexuality education upon young people's sexual behavior. 52 reports culled from a search of 12 literature databases were reviewed. The main purpose of the review is to inform policy-makers, program planners, and educators about the impact of HIV and/or sexuality education upon the sexual behavior of youth as described in the published literature. Of 47 studies which evaluated interventions, 25 reported that HIV/AIDS and sexuality education neither increased nor decreased sexual activity and attendant rates of pregnancy and sexually transmitted diseases (STDs). 17 reported that HIV and/or sexuality education delayed the onset of sexual activity, reduced the number of sex partners, or reduced unplanned pregnancy and STD rates Only 3 studies found increases in sexual behavior associated with sexuality education. Inadequacies in study design, analytic techniques, outcome indicators, and the reporting of statistics are discussed.     

The U.S. Supreme Court Decision in Jaffee v. Redmond: Implications for Counselors

In 1996, the U.S. Supreme Court held that communications between licensed psychotherapists and their patients are privileged under the Federal Rules of Evidence. The nature of privileged communication, the history of this Supreme Court decision, and implications of the decision for counselors are discussed.