In the present study, responses of 197 people who were receiving chemotherapy at two outpatient clinics and who completed a questionnaire about the presence and origin of blood-injection-injury (BII) fear were examined. From this sample, 36 participants (18.9%) reported ‘strong feelings of fear, disgust or discomfort’ towards the sight of blood, receiving injections or both. Of the 36, 7 participants (19.4%) had first noticed these concerns while they were receiving chemotherapy, and a further 19 (52.8%) reported noticing them during a traumatic experience unrelated to treatment. A subgroup of 22 participants completed the Origins Questionnaire (Menzies & Clarke, 1993). Of these participants, 7 (31.8%) were classified as having an associative onset, and 6 (27.7%) were classified as nonassociative. Only 1 participant with an associative onset attributed the fear to trauma related to chemotherapy. From these data, it appears that while a large minority of the chemotherapy patients who completed the questionnaire experienced distress associated with blood and injections, in the majority of cases the onset of these fears was not attributable to trauma associated with chemotherapy.

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 (JINS, 2007, 13, 183–189.)

Both HIV infection and methamphetamine dependence can be associated with brain dysfunction. Little is known, however, about the cognitive effects of concurrent HIV infection and methamphetamine dependence. The present study included 200 participants in 4 groups: HIV infected/methamphetamine dependent (HIV+/METH+), HIV negative/methamphetamine dependent (HIV−/METH+), HIV infected/methamphetamine nondependent (HIV+/METH−), and HIV negative/methamphetamine nondependent (HIV−/METH−). Study groups were comparable for age, education, and ethnicity, although the HIV−/METH− group had significantly more females. A comprehensive, demographically corrected neuropsychological battery was administered yielding a global performance score and scores for seven neurobehavioral domains. Rates of neuropsychological impairment were determined by cutoff scores derived from performances of a separate control group and validated with larger samples of HIV+ and HIV− participants from an independent cohort. Rates of global neuropsychological impairment were higher in the HIV+/METH+ (58%), HIV−/METH+ (40%) and HIV+/METH− (38%) groups compared to the HIV−/METH− (18%) group. Nonparametric analyses revealed a significant monotonic trend for global cognitive status across groups, with least impairment in the control group and highest prevalence of impairment in the group with concurrent HIV infection and methamphetamine dependence. The results indicate that HIV infection and methamphetamine dependence are each associated with neuropsychological deficits, and suggest that these factors in combination are associated with additive deleterious cognitive effects. This additivity may reflect common pathways to neural injury involving both cytotoxic and apoptotic mechanisms. (JINS, 2004, 10, 1–14.)Note: Dr. Erin D. Bigler served as action editor during the course of this review.

The possible medicinal use of cannabinoids for chronic diseases emphasizes the need to understand the long-term effects of these compounds on the central nervous system. We provide a quantitative synthesis of empirical research pertaining to the non-acute (residual) effects of cannabis on the neurocognitive performance of adult human subjects. Out of 1,014 studies retrieved using a thorough search strategy, only 11 studies met essential a priori inclusion criteria, providing data for a total of 623 cannabis users and 409 non- or minimal users. Neuropsychological results were grouped into 8 ability domains, and effect sizes were calculated by domain for each study individually, and combined for the full set of studies. Using slightly liberalized criteria, an additional four studies were included in a second analysis, bringing the total number of subjects to 1,188 (i.e., 704 cannabis users and 484 non-users). With the exception of both the learning and forgetting domains, effect size confidence intervals for the remaining 6 domains included zero, suggesting a lack of effect. Few studies on the non-acute neurocognitive effects of cannabis meet current research standards; nevertheless, our results indicate that there might be decrements in the ability to learn and remember new information in chronic users, whereas other cognitive abilities are unaffected. However, from a neurocognitive standpoint, the small magnitude of these effect sizes suggests that if cannabis compounds are found to have therapeutic value, they may have an acceptable margin of safety under the more limited conditions of exposure that would likely obtain in a medical setting. (JINS, 2003, 9, 679–689.)