Biomedical subjects

Alison Harris

Publications and source records attributed to Alison Harris.

5 recordsLinked to original sources

PubMed2006

Rapid face-selective adaptation of an early extrastriate component in MEG.

Adaptation paradigms are becoming increasingly popular for characterizing visual areas in neuroimaging, but the relation of these results to perception is unclear. Neurophysiological studies have generally reported effects of stimulus repetition starting at 250-300 ms after stimulus onset, well beyond the latencies of components associated with perception (100-200 ms). Here we demonstrate adaptation for earlier evoked components when 2 stimuli (S1 and S2) are presented in close succession. Using magnetoencephalography, we examined the M170, a "face-selective" response at 170 ms after stimulus onset that shows a larger response to faces than to other stimuli. Adaptation of the M170 occurred only when stimuli were presented with relatively short stimulus onset asynchronies (< 800 ms) and was larger for faces preceded by faces than by houses. This face-selective adaptation is not merely low-level habituation to physical stimulus attributes, as photographic, line-drawing, and 2-tone face images produced similar levels of adaptation. Nor does it depend on the amplitude of the S1 response: adaptation remained greater for faces than houses even when the amplitude of the S1 face response was reduced by visual noise. These results indicate that rapid adaptation of early, short-latency responses not only exists but also can be category selective.

Adaptation, Physiological↗

PubMed2003

Miniaturization of fluorescence polarization receptor-binding assays using CyDye-labeled ligands.

Fluorescence polarization (FP) is an established technique for the study of biological interactions and is frequently used in the high-throughput screening (HTS) of potential new drug targets. This work describes the miniaturization of FP receptor assays to 1536-well formats for use in HTS. The FP assays were initially developed in 384-well microplates using CyDye-labeled nonpeptide and peptide ligands. Receptor expression levels varied from approximately 1 to 10 pmols receptor per mg protein, and ligand concentrations were in the 0.5- to 1.0-nM range. The FP assays were successfully miniaturized to 1536-well formats using Cy3B-labeled ligands, significantly reducing reagent consumption, particularly the receptor source, without compromising assay reliability. Z' factor values determined for the FP receptor assays in both 384- and 1536-well formats were found to be > 0.5, indicating the assays to be robust, reliable, and suitable for HTS purposes.

Animals↗

PubMed2002

Stages of processing in face perception: an MEG study.

Here we used magnetoencephalography (MEG) to investigate stages of processing in face perception in humans. We found a face-selective MEG response occurring only 100 ms after stimulus onset (the 'M100'), 70 ms earlier than previously reported. Further, the amplitude of this M100 response was correlated with successful categorization of stimuli as faces, but not with successful recognition of individual faces, whereas the previously-described face-selective 'M170' response was correlated with both processes. These data suggest that face processing proceeds through two stages: an initial stage of face categorization, and a later stage at which the identity of the individual face is extracted.

Adolescent↗

PubMed1998

Supporting carers: is practice still sexist?

Informal carers are central to the community care policies which have emerged during the last two decades. However, research has suggested that caring is a gendered activity, disproportionately expected of women with consequent disadvantage in terms of physical and mental health and material well-being. Moreover, evidence has been presented that, in the past, women carers were less likely to be offered the support of public services than their male counterparts. A research project designed to test whether this pattern still applied in service provision to male and female spousal carers was carried out in an assessment and care management team working with older people. The results suggested that differences in professional responses to female and male carers still persist and that some workers may be unaware of the gap between their intentions and their actions in assessing and planning services. This evidence implies the need for further attention to be paid to these issues in training care managers and the importance of monitoring the outcomes of assessment along gender lines.

Journal Article↗

PubMedDate not supplied

Toilet training children with learning difficulties: what the literature tells us.

Nurses and health visitors are the professional group most likely to be involved in advising and supporting parents of children with disabilities (Bliss and Watson, 1992). Little research has been done into assessing and treating urinary continence difficulties of children with learning difficulties and many questions remain unanswered: what is the extent of the problem; what specific intervention do children with learning difficulties require to attain toileting skills; what expectation can the parent and clinician have that children with learning difficulties can be toilet trained and who is best placed to promote toileting skills? The main findings from the literature will support health and education professionals and carers who are involved in toilet training children with learning difficulties.

Adolescent↗