Inhibition of the LH Surge by Restraint Stress in Cyclic Rats: Studies on the Role of GABAA and GABAB Receptors

There is evidence that stress can alter the activity in the brain of gamma-aminobutyricacid (GABA), a neurotransmitter that has been implicated in the regulation of LH secretion. In the present study the role of GABA in the restraint stress-induced inhibition of the LH surge was investigated in the intact cyclic rat. Intracerebroventricular (icv) administration of the GABAA receptor agonist muscimol (0.1, 0.5 or 1 μg) 5 min before the presumed onset of the pro-oestrous LH surge (at 0900 h) caused a dose dependent suppression of the surge. A single dose of the GABAB receptor agonist baclofen (1 μg; icv) injected at 0855 h postponed the onset of the LH surge, and repeated injections at 0855 and 1130 h suppressed the surge. These data indicate that GABA-ergic activity in the brain can inhibit the LH surge in the cyclic rat via GABAA and GABAB receptors. Pro-oestrous rats were subjected to 5 hrs of restraint starting at 0855 h. Pretreatment with the GABAA receptor antagonist bicuculine (1 μg; icv) at 0840, 0940 and 1040 h or pretreatment with the GABAB receptor antagonist phaclofen (10 μg; icv) at 0840 h were ineffective in preventing the restraint-induced inhibition of the LH surge. The results suggest that GABAA and GABAB receptors are not involved in the inhibitory effect of restraint stress on the LH surge.     

Anticipatory grief: The search for destiny

This paper explores the dynamics between a woman dying of cancer, the man she lived with for 37 years, and the clinician who worked with them during the final months of the woman's life. Psychoanalytic perspectives on transformational and transitional object-seeking as natural processes which aid the internalization of attachment to the one who is approaching death, the creation of a primary maternal preoccupation in the caretaker, the hospice as a holding environment, and the search for destiny as a metaphor for the work of anticipatory grief are integrated with the case-material.Presented at the American Academy of Religion Annual Meeting,Person, Culture and Religion Pre-session, November, 1991.     

A comparison of operant licking and lever pressing in the rat

Two groups of rats were trained on a signaled, free-operant, avoidance procedure to lick or to lever press in order to avoid shock while water-deprived or satiated and, in the case of licking, while ingesting deionized water, isotonic saline, or 10% sucrose. The most effective avoidance licking occurred while the rats were water-deprived and ingesting 10% sucrose. Water deprivation level had no effect on lever pressing for shock avoidance. Two other groups of rats were operantly conditioned to lick or to lever press for food pellets while waterdeprived or satiated and, in the case of licking, while ingesting deionized water or 10% sucrose. The most effective licking for food reinforcement occurred while the rats were water-deprived and ingesting 10% sucrose. Water deprivation level had no effect on lever pressing for food reinforcement. The data indicated that effective operant licking must be supported by factors related to water regulation and taste palatability.     

Mother-infant interaction: effects of a home intervention and ongoing maternal drug use

Examined the effects of a home-based intervention on mother-infant interaction among drug-using women and their infants. At 2 weeks postpartum, mothers and infants were randomly assigned to either an intervention (n = 84) or a control (n = 87) group. Control families received brief monthly tracking visits, and intervention families received weekly visits by trained lay visitors. Mother-infant interaction was evaluated at 6 months through observation of feeding. Although there were no direct effects of the intervention, in the control group, mothers who continued to use drugs were less responsive to their babies than mothers who were drug free. In the intervention group, drug use was not associated with maternal responsiveness. Weekly home-based intervention may be a protective strategy for children of drug-using women because it disrupts the relation between ongoing maternal drug use and low maternal responsiveness.     

Sexual disorders not otherwise specified: compulsive, addictive, or impulsive?

Paraphilias are recurrent and intense sexually arousing fantasies, sexual urges, or behaviors generally involving nonhuman objects. These paraphilias cause the suffering or humiliation of the patient or patient's partner, or children, or other nonconsenting persons. However, in many patients symptoms involve more culturally acceptable patterns (eg, repetitive masturbation, Internet pornography); such hypersexual symptoms have been labeled as compulsive, addictive, or impulsive. Growing evidence supports the existence of a discrete syndrome characterized by recurrent and intense sexually arousing fantasies, sexual urges, or behaviors involving patterns that fall outside the definition of paraphilia. There is, however, high comorbidity with paraphilia. While such symptoms have been labeled as sexual compulsion or addiction, these terms are problematic in this context. Modern nosology has neglected this entity, although the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), category of sexual disorders not otherwise specified includes hypersexual behaviors as an example. We suggest that the DSM-IV category of sexual disorders be modified to include explicitly diagnostic criteria for a disorder characterized by hypersexual symptoms involving patterns that fall outside of the current definition of paraphilia. The disorder might be classified as one of the paraphilias, or as paraphilia-related. In the absence of a comprehensive understanding of the pathogenesis of this disorder, we suggest that it simply be termed hypersexual disorder.     

Task demands and limb apraxia in stroke

The present study was designed to examine the frequency and severity of apraxia in patients with left- or right-hemisphere stroke in both pantomime and imitation conditions and to compare the frequency of apraxia in each stroke group across the three patterns of apraxia described in Roy's model (Roy, 1996). Ninety-nine stroke patients and 15 age-matched healthy adults performed eight transitive gestures to pantomime and to imitation. Gestural performance was quantified as accuracy on five performance dimensions; a composite score, an arithmetic combination of the five performance dimensions, was used as an index of the overall accuracy. Analyses revealed a comparable proportion of patients in each stroke group were classified as apraxic in the imitation condition, but a higher proportion of left stroke patients were apraxic in the pantomime condition. The severity of apraxia in each stroke group and the performance dimensions affected were, however, comparable. Analyses of the patterns of apraxia (pantomime alone, imitation alone or apraxia in both conditions) revealed a higher frequency of apraxia in both stroke groups for the pattern reflecting apraxia in both conditions, indicating that a disruption at the movement execution stage of gesture performance was most common.     

Semantic satiation and lexical ambiguity resolution.

This study examines the effects of semantic satiation on lexical ambiguity resolution. On a given trial, participants were presented with a word triad. The first word (e.g., HEART) was presented on average 2.5, 12.5, or 22.5 times, and then participants received 2 new words for relatedness judgments. The first of the two new words was always a homograph (e.g., "ORGAN") and the other word was a related or unrelated pairmate (e.g., "KIDNEY"). In Experiment 1, when blocks of trials were intermixed with concordant (e.g., "HEART-ORGAN-KIDNEY"), discordant (e.g., "PIANO-ORGAN-KIDNEY"), and neutral (e.g., "CEILING-ORGAN-KIDNEY") trials, participants did not produce evidence of semantic satiation. In a second experiment in which only concordant and neutral trials were presented, however, participants did produce evidence of semantic satiation in the concordant condition. Taken together, Experiments 1 and 2 indicate that semantic satiation of the context-appropriate meaning of a homograph may impede ambiguity resolution.     

MESA: a new configuration for measuring electromagnetic field fluctuations

This paper describes how the multi-energy sensor array has been refitted to meet the needs of measuring geomagnetic and other types of electromagnetic phenomena in an environment. This portable laptop computer system was designed to measure the interaction of multiple frequencies with the psychological and physiological processes that underlie human exposure to electromagnetic fields across the spectra. New sensors and analytical software have been implemented in the new configuration.