Andrew Saykin and colleagues scanned the brains of 40 people who complained about their memory, but who scored normally on neuropsychological tests – all were aged 60 or over. The imaging revealed they had reduced brain cell density in their frontal and temporal lobes when compared with 40 healthy controls with no memory complaints. Moreover, their cell loss was very similar to that observed in 40 people diagnosed with mild cognitive impairment – a condition that is associated with poor scores on neuropsychological tests, and with increased risk of full-blown dementia.
“These findings highlight the importance of cognitive complaints in the clinical evaluation of older adults and suggest that those who present with significant cognitive complaints warrant evaluation and close monitoring over time”, the researchers said.
However, the researchers noted that their sample mostly consisted of highly educated participants who had above average baseline abilities, so it’s possible that not everyone will go through a phase of feeling their memory is worsening, even while performing normally on tests. “High baseline functioning or cognitive reserve may buffer the effects of brain pathology on cognition”, they said.
Saykin, A.J., Wishart, H.A., Rabin, L.A., Santulli, R.B., Flashman, L.A., West, J.D., McHugh, T.L. & Mamourian, A.C. (2006). Older adults with cognitive complaints show brain atrophy similar to that of amnestic MCI. Neurology, 67, 834-842.
Editor’s note: Don’t be overly alarmed by this study – memory difficulties can be caused by a range of factors, including stress and tiredness. However, if you’re worried about your memory, you should consult your doctor.