Biomedical subjects

A C Neubauer

Publications and source records attributed to A C Neubauer.

4 recordsLinked to original sources

PubMed2004

Intelligence and working memory systems: evidence of neural efficiency in alpha band ERD.

Starting from the well-established finding that brighter individuals display a more efficient brain function when performing cognitive tasks (i.e., neural efficiency), we investigated the relationship between intelligence and cortical activation in the context of working memory (WM) tasks. Fifty-five male (n=28) and female (n=27) participants worked on (1) a classical forward digit span task demanding only short-term memory (STM), (2) an attention-switching task drawing on the central executive (CE) of WM and (3) a WM task involving both STM storage and CE processes. During performance of these three types of tasks, cortical activation was quantified by the extent of Event-Related Desynchronization (ERD) in the alpha band of the human EEG. Correlational analyses revealed associations between the amount of ERD in the upper alpha band and intelligence in several brain regions. In all tasks, the males were more likely to display the negative intelligence-cortical activation relationship. Furthermore, stronger associations between ERD and intelligence were found for fluid rather than crystallized intelligence. Analyses also point to topographical differences in neural efficiency depending on sex, task type and the associated cognitive subsystems engaged during task performance.

Adolescent↗

PubMed2003

Sensitivity of human EEG alpha band desynchronization to different working memory components and increasing levels of memory load.

Event-related alpha band desynchronization is frequently used to analyze spatiotemporal cortical activation patterns during the performance of cognitive tasks. In the present paper the sensitivity of alpha band desynchronization to increasing levels of cognitive load and to different cognitive working memory components is investigated. A 27-channel electroencephalogram of 62 participants while solving (a) a short-term memory and (b) a working memory task (dual task), each with five levels of memory load, was analyzed. We found (a) a linearly increasing desynchronization in the upper alpha band with ascending cognitive load, and (b) evidence of the involvement of distinguishable cognitive components (storage and controlled attention) in the memory tasks.

Alpha Rhythm↗

PubMed1995

Ultradian rhythms in cognitive performance: no evidence for a 1.5-h rhythm.

In the past, Kleitman's notion of a basic rest-activity cycle (BRAC), which states an approximate 1.5-h rhythm of arousal, has received some empirical support in studies investigating physiological or psychological parameters. Our study investigated this ultradian rhythm in human cognitive performance. Sixty subjects were tested every 10 min for 9 h with an elementary cognitive task, the sentence-verification test (SVT), and provided ratings of alertness and mood. Heart period was always measured during performance of the SVT. Using rather conservative statistical methods, spectral analyses of time series revealed no significant 90-min periodicity for any of the variables. Instead, longer periodicities were the major sources of variance. Reanalyses using detrended and/or smoothed time series suggest that emergence of the BRAC might depend also on statistical methods. In conformity with recent studies it was concluded that several positive reports for the BRAC might be due to lack of conservatism in statistical methods.

Adult↗

PubMed1992

AIDS and Austrian physicians.

Physicians have key roles both in treating disease and educating their patients about health and disease-related issues. To assess which factors correlate with Austrian physician's willingness to treat and educate patients about HIV-related risk behaviors and deal with AIDS issues, we conducted a survey of general practitioners, internists, and dermatologists in Graz, Austria. We report on some aspects of the knowledge, attitudes, and practices of these physicians. Factor analysis revealed two attitudinal components significantly associated with HIV-related practices of the respondents. We labeled these components Reluctance and Infection. "Reluctance" reflected discomfort with sex-related matters and was associated with less HIV counseling and less interest in HIV-related continuing medical education. "Infection" reflected a fear of contracting HIV disease and was positively associated with an increased assessment of different risk factors and a tendency to refer HIV-infected patients for all further treatment. Results suggest that physicians need further training in their ability to deal with HIV issues. Fortunately they seem willing to improve and take further training to do so. Patients, physicians, and the public would all benefit from acknowledging and dealing with the attitudes and needs of physicians toward HIV-related issues.

Acquired Immunodeficiency Syndrome↗