Monthly Archives: August 2012

Older brains communicate differently

Ageing makes the networks in our brain less specific. Linda Geerligs, one of PredSL PI Natasha Maurits’ PhD students, used connectivity analysis of fMRI results to prove that the connections in our brain change as we grow older.

When compared with their younger counterparts, connectivity in the brain networks of older people decreases, while connectivity between brain networks increases. Linda also found evidence to suggest that the decrease in connectivity in the brain networks corresponds with slower reaction times and declining memory among the elderly. The research findings have been published online in Human Brain Mapping today.

The insights provided by this kind of fundamental research are very interesting. If we can discover exactly what changes in the brain during the ageing process and what the effects of these changes are, this will give us new leads for finding new treatments for elderly people with concentration and memory problems.

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Increased beta band phase locking compensates for decreased inhibition in elderly?

Today, Linda Geerligs, PhD student in Experimental Psychology and supervised by Monicque Lorist and PredSL PI Natasha Maurits, published a paper in the Journal of Cognitive Neuroscience on the effects of age on the suppression of irrelevant information.

The extent of decline of inhibitory functions with age is highly variable between individuals. In this study, Linda used event-related potentials (ERPs) and phase locking analyses to investigate neural correlates of this variability in inhibition between individuals. Older and younger participants performed a selective attention task in which relevant and irrelevant information was presented simultaneously. The participants were split into high and low performers based on their level of inhibition inefficiency, that is, the slowing of reaction times induced by information that participants were instructed to ignore. Efficient inhibition in both age groups was related to increased functional connectivity in the alpha band between frontal and occipito-parietal areas in the prestimulus interval. In addition, increased power in the alpha band in occipito-parietal areas was related to better inhibition both before and after stimulus onset. Phase locking in the upper beta band before and during stimulus presentation between frontal and occipito-parietal regions was related to better performance in older participants only, suggesting that this is an active compensation mechanism employed to maintain adequate performance. In addition, increased top-down modulation and increased power in the alpha band appears to be a general mechanism facilitating inhibition in both age groups.

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