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Jennifer E Iudicello

Publications and source records attributed to Jennifer E Iudicello.

2 recordsLinked to original sources

Verbal fluency in HIV infection: a meta-analytic review.

Given the largely prefrontostriatal neuropathogenesis of HIV-associated neurobehavioral deficits, it is often presumed that HIV infection leads to greater impairment on letter versus category fluency. A meta-analysis of the HIV verbal fluency literature was conducted (k = 37, n = 7110) to assess this hypothesis and revealed generally small effect sizes for both letter and category fluency, which increased in magnitude with advancing HIV disease severity. Across all studies, the mean effect size of category fluency was slightly larger than that of letter fluency. However, the discrepancy between category and letter fluency dissipated in a more conservative analysis of only those studies that included both tests. Thus, HIV-associated impairments in letter and category fluency are of similar magnitude, suggesting that mild word generation deficits are evident in HIV, regardless of whether traditional letter or semantic cues are used to guide the word search and retrieval process.

Acquired Immunodeficiency Syndrome↗

Tolcapone improves cognition and cortical information processing in normal human subjects.

Prefrontal cortical dopamine (DA) regulates various executive cognitive functions, including attention and working memory. Efforts to enhance prefrontal-related cognition, which have focused on catecholaminergic stimulant drugs, have been unsatisfactory. Recently, the demonstration that a functional polymorphism in the catecholamine-O-methyltransferase (COMT) gene impacts prefrontal cognition raises the possibility of a novel pharmacological approach for the treatment of prefrontal lobe executive dysfunction. To explore in a proof of concept study the effects of tolcapone, a CNS penetrant specific COMT inhibitor, we performed a randomized, double blind, placebo controlled, and crossover design of this drug in normal subjects stratified by COMT (val158met) genotype. COMT enzyme activity was determined in peripheral blood. Forty-seven normal volunteers with no family history of psychiatric disorders underwent neuropsychological testing and 34 of those subjects underwent physiological measurement of prefrontal information processing assessed by blood oxygen level-dependent functional magnetic resonance imaging (fMRI). We found significant drug effects on measures of executive function and verbal episodic memory and a significant drug by genotype interaction on the latter, such that individuals with val/val genotypes improved, whereas individuals with met/met genotypes worsened on tolcapone. fMRI revealed a significant tolcapone-induced improvement in the efficiency of information processing in prefrontal cortex during a working memory test. This study demonstrates enhancement of prefrontal cortical function in normal human subjects with a nonstimulant drug having COMT inhibitory activity. Our results are consistent with data from animal studies and from computational models of the effects of selective enhancement of DA signaling in the prefrontal cortex.

Adult↗