News Round-Up: August 2009 5th Edition

News In Brief

The authors of a Finnish study state that they have found evidence that astrocytes mediate the blood vessel changes that are seen in fMRI studies and it will be interesting to see further information on this study as it becomes available. A Stanford study published in the Proceedings of the National Academy of Sciences looked at 100 students, examining how they responded to the data they were presented with. The students were divided into those that those frequently ‘media multitask’ (which means that they take in information from multiple media sources which is contrasted with focusing on a single task at any given time) with those who did not. The group found that the multitaskers performed worse than the comparison group on a number of measures including distractability. The study has been widely reported (e.g. here, here, here and here). In the Blogosphere, the study has been covered over at MindHacks and Not Exactly Rocket Science and the key point is that this study is demonstrating association rather than causality. So for instance, the heavy multitaskers may use this approach because they have a different cognitive profile.

An American cross-sectional study involving 559 women found an association between hopelessness and thickness of the carotid arteries which remained after controlling for depression and other cardiovascular risk factors. The arterial wall thickness is a risk factor for cardiovascular and cerebrovascular disease but it will be interesting to see replication using a prospective study design. One research team have used ambient background noise during training exercise to help people with Parkinson’s Disease learn how to speak louder as the condition can affect their expressive speech. The team is now looking to make small modifications to their approach – they are. There has been confirmation of the efficacy of delivery of a gene for Nerve Growth Factor in a murine model of Parkinson’s Disease in one study. The gene was delivered using a modified Adenovirus and the expression of the gene was modified with Doxycycline. A study in flies demonstrating two pathways – one for long term memory and the other for short-term memory may be of relevance to humans as there is a human homologue of a gene involved in these memories – Rutabaga.

A large study provided some preliminary evidence of a relationship between increasing diastolic blood pressure and cognitive impairment in people over the age of 45. The study involved 30,228 subjects from the longitudinal REGARDS study (Reasons for Geographic and Racial Differences in Stroke) but the association here was drawn from cross-sectional data obtained from the cohort and so it would be interesting to see replication using longitudinal data and other cognitive measures that are used for assessment of mild cognitive impairment. One study looking at older adults (over the age of 70)  (n=94) investigated the relationship between Body Mass Index and cortical volume as measured using tensor based morphometry. The researchers found a significant association between increasing Body Mass Index and a reduction in cortical volume and it would be interesting to see large replication studies.

A German team have provided evidence that two Parkinson’s Disease associated genes – Parkin and PINK1 interact to maintain mitochondrial function and the researchers suggest that this may have implications for possible disease-modifying therapies. In a study of people who had developed concussion (20 subjects and 20 controls), neuropsychological testing identified executive impairment but CT and MRI scans did not pick up evidence of injury. However the researchers also used Diffuse Tensor Imaging and were able to identify areas of injury with particular involvement of the prefrontal cortex which was consistent with the neurospychology results. The researchers also found a significant association between the DTI identified injury and the executive performance providing and the research team suggest that this provides evidence for a role for DTI in concussion.

The results of one study indicated equivalent efficacy for both red and blue light in maintaining nighttime alertness. In another study when looking at a clock subjects gave different times when either the clock was brought into their field of vision (in which case the time they gave fell behind the actual time) or if their eyes moved to the clock (in which case the time they gave was ahead of the actual time) and the results were interpreted as meaning that the cortical visual perceptual system anticipates the movement of the eyes. A candidate gene KIAA0319 (on Chromosome 6) was investigated in 322 children with Specific Language Impairment and variations were found to be associated with language ability.

Podcast

You can listen to this post on Odiogo by clicking on this link (there may be a small delay between publishing of the blog article and the availability of the podcast).

Responses

If you have any comments, you can leave them below or alternatively e-mail justinmarley17@yahoo.co.uk

Disclaimer

The comments made here represent the opinions of the author and do not represent the profession or any body/organisation. The comments made here are not meant as a source of medical advice and those seeking medical advice are advised to consult with their own doctor. The author is not responsible for the contents of any external sites that are linked to in this blog

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