Alterations of emotional reactivity following righttemporal lobectomy.

To learn if a right temporal lobectomy altered a patient's autonomic and cognitive responses to aversive and appetitive pictures, we investigated a man whose right anterior temporal lobe and amygdala had been resected to remove an arteriovenous malformation. This patient revealed unusually low self-reports of arousal with a lack of heightened skin conductance responses to aversive pictures. For pleasant pictures, his self-reports of arousal and his physiological responses were similar to healthy men. This patient's responses are consistent with a bivalent model of emotional processing, with a right temporal lobectomy compromising the activation of his defensive action response system.

Reducing infectivity of HIV upon exposure to surfaces coated with N,N-dodecyl, methyl-polyethylenimine.

The infectivity of high-titer, cell-free HIV in culture media and human milk is rapidly reduced upon exposure to polyethylene slides painted with the linear hydrophobic polycation N,N-dodecyl,methyl-polyethylenimine (DMPEI). Accompanying viral p24 protein and free viral RNA analysis of solutions exposed to DMPEI-coated surfaces suggests that virion attachment to the polycationic surface and its subsequent inactivation are the likely mechanism of this phenomenon.

Attention mediates radiation's impact on daily living skills in children treated for brain tumors.

BACKGROUND: Radiotherapy is associated with an increased survival rate in children with brain tumors, but also with cognitive decline. This study examined the time-dependent effects of radiation treatment on adaptive functioning in children with brain tumors. The potentially mediating effects of attention span (Trial 1 of the Rey Auditory Verbal Learning Test [RAVLT]) assessed within 7 years of diagnosis were explored. PROCEDURE: Twenty-two children treated with cranial radiation for third ventricle or cerebellar tumors were included in this archival study. The mean age at diagnosis was 7.62 years (SD = 4.78) and 10.16 years (SD = 3.83) at evaluation. We examined the extent to which auditory attention span was able to mediate the relationship between time elapsed since the initiation of radiation treatment (M = 2.43 years; SD = 2.37) and adaptive functioning (Vineland Adaptive Behavior Scales [VABS]). RESULTS: Attention span was found to mediate the relationship between time since the initiation of radiation and daily living skills. These findings were shown to be specific to attention and not a reflection of generalized neuropsychological decline, nor were they a result of increasing time since diagnosis in and of itself. CONCLUSIONS: The results of this study suggest that time since radiation may directly decrease attention and poor attention in turn may be associated with lower adaptive functioning on tasks of daily living.

Attention and memory in children with brain tumors.

The Rey Auditory Verbal Learning Test was utilized to examine attention, learning, and memory abilities in 42 children with cerebellar (N = 18) and third ventricle tumors (N = 24). Children with cerebellar tumors exhibited significant auditory attentional impairments and displayed adequate encoding and retrieval across subsequent learning and memory trials. In contrast, children with third ventricle tumors exhibited average auditory attentional abilities, but they displayed mild encoding deficits across trials 2-5. Furthermore, the third ventricle group's compromised performance on the delayed recall trial and average performance on the delayed recognition trial is suggestive of underlying retrieval deficits.

Semantic, executive, and visuospatial abilities in mathematical reasoning of referred college students.

Semantic retrieval (SR) and executive-procedural (EP), but not visuospatial (VS) skills, have been found to be uniquely predictive of mathematical calculation skills in a sample of clinically referred college students. This study set out to cross-validate these results in an independent sample of clinically referred college students (N = 337) as well as extend them by examination of the contributions of these cognitive domains to math reasoning skills. Results indicate that these cognitive domains were able to predict 30% of the variance in calculation skills and 50% of the variance in math reasoning; however, in both cases, only the domains of semantic retrieval and visuospatial skill contributed uniquely. Differences between studies, and the lack of unique contribution of the EP domain to either type of math skill, may be due to measurement and sampling differences, the degree of shared relations among domains, and the choice of measures that represent the EP domain. Implications and future directions are explored.

Evaluation of the double-deficit hypothesis in college students referred for learning difficulties.

The present study explored the double-deficit hypothesis (DDH) in a sample of 146 college students with and without reading disabilities (RD). The results indicated that although both phonological awareness (PA) and visual naming speed (VNS) contributed to performance on measures of decoding and comprehension, their relative contribution was influenced both by the nature of the stimulus (word vs. nonword vs. text) and by the conditions of the task (timed vs. untimed). Similar results were obtained using an individual differences approach, or when between-group comparisons were made of individuals with deficits in PA or VNS. The relative representation of DDH subgroups in groups of adults with RD varied based on the classification criteria used to define RD. These results support the DDH, extend its applicability to adults, and have implications for diagnostic decision making.

Reading and phonological awareness in reading-disabled adults.

Sixty-eight students with reading disabilities (RDs) and 55 non-reading-disabled university undergraduates composed the sample. Students with RDs met either low achievement (LA) or regression-based discrepancy (D) criteria. In addition to IQ and reading decoding measures, all participants received measures of phonological awareness (PA), confrontation naming, and verbal fluency. Consistent with expectations, the D and LA subgroups did not differ from one another, and both performed worse than students without RD on phonological measures. However, only the LA subgroup performed worse on measures of confrontation naming and verbal fluency. Subgroups of readers who had LA without an IQ-achievement discrepancy (LA-no D) and readers who had both LA and a discrepancy (LA + D), performed worse than readers who had a discrepancy but whose reading achievement was above the 16th percentile (D-no LA) on measures of PA, naming, and fluency; this subgroup did not differ from students without RDs. These results question the utility of determining RD in adults solely on the basis of IQ-achievement discrepancy criterion without regard to other linguistic skills or absolute reading level.

Neuropsychological concomitants of calculation skills in college students referred for learning difficulties.

The contributions of 3 conceptual domains from a theoretical model of math skill (Geary, 1993) were examined in a large sample of college students referred for assessment of possible learning disorders. Measures were chosen from a comprehensive neuropsychological battery, and from the Wechsler Adult Intelligence Scale-Revised, to represent each of the 3 domains (semantic retrieval, executive-procedural, and visuospatial). The proposed model was examined using structural equation modeling (LISREL), and factors representing the 3 latent domains were derived. The domains of semantic retrieval and executive-procedural skills together accounted for approximately 17% of the variance in calculation skills. The domain of visuospatial skills failed to account for significant incremental variance.

Concordance of self- and informant ratings of adults' current and childhood attention-deficit/hyperactivity disorder symptoms.

Self-informant rating concordance for attention-deficit/hyperactivity disorder (ADHD) symptoms was assessed in 281 adults at the subscale (Inattention, Hyperactivity-Impulsivity) and individual symptom levels. Potential demographic, diagnostic, and informant identity moderators were also investigated. Concordance levels were similar for current and childhood symptoms. Although moderate positive correlations were found between self- and informant ratings on both subscales, informants endorsed more significant inattentive symptom severity. Kappa coefficients were variable, suggesting low concordance for certain symptoms. Sex and ADHD diagnosis moderated concordance, although effect sizes were small. These results have implications for the use of behavior rating scales in diagnosing ADHD, raise questions about the validity of self- and informant ratings, and support the need to investigate individual-differences variables that may impact concordance.

Discrimination of ADHD and reading disability in adults using the D-KEFS.

Attention deficit/hyperactivity disorder (ADHD) is posited to be the result of a deficit in executive functions (EFs). The presence of EF deficits in adults with ADHD is not consistent, and EF deficits are not unique to ADHD, thus adding a level of complexity to differential diagnoses. The current study used three measures of EF to discriminate between college-level adults diagnosed with ADHD and reading disability (RD). The RD group performed below ADHD on all EF tasks and logistic regression analyses demonstrated poor sensitivity and adequate specificity of the EF measures to categorize the clinical groups. Results suggest that clinicians should be cognizant of the limitations of measures of EF in the differential diagnosis of ADHD.

A nipple shield delivery system for oral drug delivery to breastfeeding infants: microbicide delivery to inactivate HIV.

A new drug delivery method for infants is presented which incorporates an active pharmaceutical ingredient (API)-loaded insert into a nipple shield delivery system (NSDS). The API is released directly into milk during breastfeeding. This study investigates the feasibility of using the NSDS to deliver the microbicide sodium dodecyl sulfate (SDS), with the goal of preventing mother-to-child transmission (MTCT) of HIV during breastfeeding in low-resource settings, when there is no safer alternative for the infant but to breastfeed. SDS has been previously shown to effectively inactivate HIV in human milk. An apparatus was developed to simulate milk flow through and drug release from a NSDS. Using this apparatus milk was pulsed through a prototype device containing a non-woven fiber insert impregnated with SDS and the microbicide was rapidly released. The total SDS release from inserts ranged from 70 to 100% of the average 0.07 g load within 50 ml (the volume of a typical breastfeed). Human milk spiked with H9/HIV(IIIB) cells was also passed through the same set-up. Greater than 99% reduction of cell-associated HIV infectivity was achieved in the first 10 ml of milk. This proof of concept study demonstrates efficient drug delivery to breastfeeding infants is achievable using the NSDS.

Psychological adjustment, substance use, HIV knowledge, and risky sexual behavior in at-risk minority females: developmental differences during adolescence.

OBJECTIVE: To assess developmental differences in the psychological functioning, substance use, coping style, social support, HIV knowledge, and risky sexual behavior of at-risk, minority adolescent girls; to assess developmental differences in psychosocial correlates of risky sexual behavior in older and younger adolescents. METHOD: Participants included 164 minority teens, ages 12-19, who were receiving medical care in an adolescent primary care clinic. Teens completed measures of psychological adjustment, substance use, coping style, social support, religious involvement, and HIV knowledge and attitudes. In addition, they answered questions regarding their sexual history, family situation, school status, and psychiatric and legal history. RESULTS: Younger teens (ages 12-15) reported more symptoms of depression and earlier sexual debuts than older teens (ages 16-19). However, older teens reported significantly more substance use and were more likely to have been pregnant and to have contracted a sexually transmitted disease (STD) than younger teens. Older teens also reported more religious involvement and using more adaptive coping strategies than younger teens. Developmental differences in the correlates of risky behaviors were also found between younger and older teens. Specifically, conduct problems and substance use were significantly associated with risky sexual behavior for younger teens, but not for older teens. Similarly, younger teens whose peers were engaging in risky behaviors reported engaging in more risky sexual behaviors; however, these same relations were not found for older teens. CONCLUSIONS: Young minority adolescents exhibiting conduct problems and using substances seem to be at highest risk for contracting HIV and STDs as a result of risky sexual behavior. Prevention interventions should target teens in high-risk environments during late elementary school or early middle school to encourage teens to delay intercourse, practice safer sex, and avoid drug and alcohol use. An interdisciplinary model of care in primary care settings is clearly indicated to provide these services to at-risk youths.

Predictors of risky sexual behavior in African American adolescent girls: implications for prevention interventions.

OBJECTIVE: To describe empirically the risky sexual behavior of an at-risk sample of adolescent girls, to assess psychosocial correlates of risky behavior, and to examine the utility of applying a risk and protective model to predicting teens' risky sexual behavior. METHOD: Participants included 158 African American girls, ages 12 to 19, who were receiving medical care in an adolescent primary care clinic. Teens completed measures of depression, conduct problems, substance use, peer norms, social support, HIV knowledge, sexual self-efficacy, and sexual behavior. RESULTS: Teens in this sample reported high rates of risky sexual behaviors, including early sexual debuts and frequent unprotected sexual encounters with multiple partners. African American girls who reported high rates of substance use and who reported that their peers engaged in risky behaviors also reported engaging in high rates of risky sexual behaviors. Little support was obtained for protective factors (HIV knowledge, social support, sexual self-efficacy) moderating the relations between risk factors and adolescents' risky sexual behavior in this sample. CONCLUSIONS: Teens presenting in primary care settings in urban environments seem to be at high risk for HIV, STDs, and substance abuse, and risk reduction strategies should be introduced during the preteen years. An interdisciplinary model of care in primary care settings serving adolescents is clearly indicated, and prevention-oriented interventions aimed at reducing risky behaviors and preventing the development of more significant health, mental health, or substance abuse disorders are needed.