Biomedical subjects

E A Attree

Publications and source records attributed to E A Attree.

6 recordsLinked to original sources

PubMed1996

Age and recovery from brain injury: clinical opinions and experimental evidence.

For many years the notion that brain damage causes less impairment in children than in adults (sometimes known as the 'Kennard Principle') has enjoyed widespread support among scientists and clinicians. More recently neuroscientists have questioned the Principle, most now taking an opposing view that damage to the rapidly developing brain can be more harmful than equivalent damage in adulthood. Many clinicians, however, appear reluctant to reject the Kennard Principle. This study investigates the extent to which the Kennard Principle still guides the judgement of different groups of health-care professionals (neurosurgeons, neurologists, neuropsychologists, general practitioners, nurses, physiotherapists, occupational therapists, and speech therapists). Subjects were asked to estimate the extent of recovery in clinically based but fictitious case studies which differed only in the reported age of the patient. The professions differed in their levels of optimism regarding the extent of recovery to be expected, but all predicted better recovery in younger patients (under 10) than in adults with otherwise similar brain injuries. The results are discussed in terms of their implications for the treatment of brain injuries in the young.

Adult↗

PubMed1996

Virtual reality: an assistive technology in neurological rehabilitation.

The need for improved neurological rehabilitation strategies is self-evident. Recent developments in the computer technology of virtual reality hold the promise of exciting progress in this area. In this paper four areas of potential application of virtual reality to neurological rehabilitation are reviewed.

Activities of Daily Living↗

PubMed1993

Environmental enrichment following brain damage: an aid to recovery or compensation?

Postoperative environmental enrichment (EC) in rats with brain lesions has been hailed as a potential agent of recovery of function following brain damage. However, most such claims are based on examining the effects of EC on acquisition of a new task following brain injury. Elsewhere we have argued that since this paradigm fails to establish a preoperative behavioural baseline against which to compare subsequent performance it may demonstrate compensation but cannot provide evidence of recovery. The present study directly addresses this issue by examining the effects of postoperative EC both on performance of a preoperatively acquired water maze escape response as well as on de novo acquisition of such a response in rats with bilateral occipital and sham lesions. In terms of swim times postoperative EC was found to significantly improve the performance of subjects which had not been preoperatively trained but not the performance of those subjects which had. However, in terms of a trials to criterion measure postoperative EC benefitted animals in both the preoperative and postoperative training conditions. The results, therefore, support the view that what has been observed in most previous studies is EC-induced compensation rather than recovery and also help to define the conditions under which this occurs. However, they also argue for further investigation of the hypothesis that postoperative EC may enhance recovery of lesion-impaired performance consistency.

Animals↗

PubMed1993

How does environmental enrichment aid performance following cortical injury in the rat?

Understanding how postoperative environmental brain damage in animals may help in devising treatment regimes for brain injured humans. This study tests Finger's hypothesis that EC increases the animal's ability to switch to alternative cues when brain damage renders the cues normally used in performing the task less salient or unavailable. Following preoperative water maze training to visual cues, rats were given either bilateral occipital lesions or sham operations, housed in either EC or standard conditions and then tested in the water maze in alternating visual and non-visual cue conditions. We found no evidence that postoperative EC helped lesioned rats to switch to non-visual cues when visual cues were unavailable.

Acclimatization↗

PubMed1992

Maternal hypothyroxinemia and brain development: II. Biochemical, metabolic and behavioural correlates.

Using a rat model, we have investigated the influence of maternal hypothyroxinemia throughout pregnancy on brain development in young and adult progeny. Although no consistent change was observed in whole brain total protein concentration, the subcellular distribution of protein was adversely affected. Isolation of glycoprotein from developing brain by concanavalin A-affinity chromatography and subsequent resolution by gel electrophoresis revealed the selective compromise of particular glycoprotein species. Furthermore, both control and experimental progeny expressed unique glycoprotein species which either persisted over the period studied or were transient. Calcineurin, a regulator of neurite elongation, was compromised in young progeny, as were a number of lysosomal enzymes (beta-D-glucosidase and aryl sulphatase). In adult progeny, the content of cerebroside sulphate (a major myelin galactolipid) was reduced in midbrain and paleocortex, and brain region-specific compromise was observed for acetylcholine metabolic enzymes. These changes were associated with alterations in behavioural output. We conclude that the availability of maternal thyroxine to the fetus may be a critical determinant for normal brain development and function.

Animals↗

PubMed1989

The relationship between laterality and numerical and spatial ability.

Hypotheses derived from right shift theory concerning the relationship between laterality and mathematical ability were investigated. This was done by dividing a group of 129 subjects into subgroups with presumably different distributions of the rs+ +, rs+ - and rs- - genotypes on the basis of their manual skills and then assessing their numerical and spatial abilities. No relationship was found between laterality and ability when the group as a whole were considered, but some marginal effects were found for numerical ability when data for a subgroup of 96 young female subjects were analysed separately. The results did not, however, conform to the predictions of right shift theory.

Adolescent↗