Faculty Bibliography

This study evaluated the equivalence of five forms of the Selective Reminding Test, a widely used measure of verbal learning, 45 normal young and 45 normal elderly subjects were randomly administered three of the five test forms on three separate sessions. The five forms generally correlated well with one another and were of comparable difficulty, suggesting adequate test equivalence. Four of the five forms were particularly well matched

Despite widespread use of antidepressants, major gaps remain in our knowledge of the effects of antidepressants on human performance. While most single-dose studies with normal subjects have suggested that the more sedating tricyclic antidepressants tend to produce impairment, the effects of antidepressant treatment in clinical populations have been less thoroughly examined, with both drug-induced impairment and improvement reported. This review suggests that factors such as age, diagnosis, drug plasma concentration, and length of treatment need to be explored to establish the effects of antidepressants on performance in clinical populations

The concentration of corticotropin-releasing factor-like immunoreactivity (CRF-LI) in the cerebrospinal fluid (CSF) of 15 probable Alzheimer's disease (AD) patients with mild to moderate dementia and 10 neurologically normal age-matched controls was examined. There were no significant alterations in the mean CSF CRF-LI concentration in AD compared to controls. However, in the AD group, CSF CRF-LI correlated significantly with the global neuropsychological impairment ratings, suggesting that greater cognitive impairment was associated with lower CSF CRF-LI concentrations. There was a significant reduction in the CSF concentration of homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) in the AD patients, and there was a positive correlation between the concentration of CRF-LI and 5-HIAA in CSF. This latter finding suggests that serotoninergic neuronal systems may interact with CRF-containing neurons

The authors studied CSF gamma-aminobutyric acid (GABA) in 14 Alzheimer patients and nine age-matched normal subjects. The five normal subjects who were wives of the demented patients had higher CSF GABA concentrations than the four normal subjects without demented spouses

In contrast to the well established presynaptic cholinergic deficits which are associated with Alzheimer's Disease (AD), the functional status of the remaining muscarinic receptors has not received adequate attention. This paper examined the possibility that the presynaptic cholinergic deficits in AD may be accompanied by muscarinic supersensitivity. While the majority of QNB binding studies have failed to find an upregulation of muscarinic receptors in AD patients, most of those studies did not differentiate between presynaptic and postsynaptic receptors. In addition, receptor density and functional response are not necessarily correlated. To determine whether AD is accompanied by alterations in the functional status of central muscarinic receptors, we studied the biological responses to a muscarinic agonist in AD patients and controls. In this pilot study, AD patients demonstrated an increased arecoline-induced HVA response in the CSF. This finding is consistent with the hypothesis that AD is accompanied by muscarinic supersensitivity

The administration of a single dose of the opiate antagonist naltrexone (NT) was accompanied by significant elevations in plasma cortisol in normal elderly subjects; in contrast, the cortisol response to NT was absent in individuals of comparable age with Alzheimer's disease (AD). The differential effect of AD on the cortisol response was not accompanied by a significant group difference in plasma prolactin in response to NT administration. Furthermore, this differential cortisol response to NT was not associated with any evident differences in age, sex ratio, plasma levels of naltrexone or its major metabolite beta-naltrexol, or with differences in measures of nonspecific stress, such as plasma free MHPG, pulse, or blood pressure, between the two groups. The absence of the well-characterized cortisol response to NT in AD, together with other reports of abnormal responses to other pharmacological challenges, suggests that neuroendocrine abnormalities might be an important concomitant and possibly a central contributor to the pathophysiology of Alzheimer's disease