Alzheimer's drugs improve perception

05/2013

Most of the (few) approved Alzheimer’s drugs are cholinesterase inhibitors — that is, they stop the breakdown of the neurotransmitter acetylcholine. A new study explains why they help. It appears they allow signals to enter the brain with more precision and less background noise.

The study involved 13 healthy young adults, some of whom were given the cholinesterase inhibitor galantamine, before listening to a series of modulating tones while focusing on a simple concentration task. The patterns of neural activity demonstrated by those on the drug most closely fit a model in which the signals coming into the brain were sharpened. This was something of a surprise, since it has been generally assumed that the effects would be most pronounced in the ‘higher-order’ processing regions.

The findings are an interesting reminder of the importance of sensory perception for optimal cognition. It should be noted, though, that this sharpening of the signal did occur in an environment in which the stimuli were predictable.

http://www.eurekalert.org/pub_releases/2013-05/vt-taf050713.php

[3407] Moran, R. J., Campo P., Symmonds M., Stephan K. E., Dolan R. J., & Friston K. J.
(2013).  Free Energy, Precision and Learning: The Role of Cholinergic Neuromodulation.
The Journal of Neuroscience. 33(19), 8227 - 8236.

Related News

A certain level of mental decline in the senior years is regarded as normal, but some fortunate few don’t suffer from any decline at all.

Previous research has found that carriers of the so-called

Obesity has been linked to cognitive decline, but a new study involving 300 post-menopausal women has found that higher BMI was associated with higher cognitive scores.

In the last five years, three studies have linked lower neighborhood socioeconomic status to lower cognitive function in older adults. Neighborhood has also been linked to self-rated health, cardiovascular disease, and mortality.

A telephone survey of around 17,000 older women (average age 74), which included questions about memory lapses plus standard cognitive tests, found that getting lost in familiar neighborhoods was highly associated with cognitive impairment that might indicate Alzheimer’s.

The very large and long-running Women's Health Initiative study surprised everyone when it produced its finding that hormone therapy generally increased rather than decreased stroke risk as well as other health problems.

Research has shown that younger adults are better decision makers than older adults — a curious result. A new study tried to capture more ‘real-world’ decision-making, by requiring participants to evaluate each result in order to strategize the next choice.

In a study involving 115 seniors (average age 81), those who participated in a six-week, 12-session memory training program significantly improved their verbal memory.

Following a 1994 study that found that errorless learning was better than trial-and-error learning for amnesic patients and older adults, errorless learning has been widely adopted in the rehabilitation industry.

In the study, 18 children (aged 7-8), 20 adolescents (13-14), and 20 young adults (20-29) were shown pictures and asked to decide whether it was a new picture or one they had seen earlier.

Pages

Subscribe to Latest newsSubscribe to Latest newsSubscribe to Latest health newsSubscribe to Latest news