November 14, 2017

expert reaction to non-peer-reviewed research on how sports-related head injuries may temporarily impair memory

An abstract presented at the Neuroscience 2017 conference investigates whether participation in a contact sport may temporarily impair memory.

Dr Richard Greenwood, Consultant Neurologist, Homerton Hospital and the National Hospital for Neurology and Neurosurgery, UCLH, said:

“Previous work using advanced imaging techniques has demonstrated that non-concussive sport head injuries can lead to structural changes in the brain. In this study the researchers have used the mnemonic similarity test (MST) as a measure of hippocampal memory, and thus hippocampal plasticity. But it is not clear from the abstract why the results are thought to reflect the effect of reduced hippocampal neurogenesis, rather than some other structural change. So at this point there is not enough information to tell us whether the claims in the press release are supported by strong evidence.”

Dr Alan Carson, Reader in Neuropsychiatry, University of Edinburgh, said:

“The finding that recently concussed individuals have abnormalities in attention, anterograde memory and speed of processing which normalises after a few weeks has been well established since the World Health Organisation’s 2004 review of the existing literature. The existing literature is also clear that these early deficits reverse and do not associate with longer-term memory problems. Further, they are often linked to pre-existent problems with mood state and social variables.

“This small study does not add anything of note to already known findings. In particular, the use of the mnemonic similarity test (MST) is not as precise as claimed, it is easily contaminated from numerous confounding factors including medication, mood state, anxiety, and effort, and one cannot impute mechanism in this way form a small study. The conclusions are overstated and I have been concerned about the quality of a lot of recent concussion claims and the potential unnecessary anxiety caused by overstating claims to a concerned public.”

* ‘Concussion and a single season of contact sport participation affect performance on a test of high memory interference’ by McCradden et al. was presented at Neuroscience 2017 conference on Tuesday 14^th November.

All our previous output on this subject can be seen at this weblink: http://www.sciencemediacentre.org/?s=brain%20trauma%20sport&cat

Declared interests

Dr Greenwood: “No conflicts of interest”

Dr Carson: “No conflicts of interest”