Cognitive training improves insomnia sleep quality
medwireNews: Older adults with insomnia could benefit from computerized cognitive training, which researchers have found helps in the initiation and maintenance of sleep.
They also report that such training improved cognitive functioning, and this improvement predicted better sleep quality.
"Although causal relationships cannot be inferred…, it is quite likely that the improvements in cognitive function drove the improvements in sleep quality," say Iris Haimov (Yezreel Academic College, Israel) and Evelyn Shatil (CogniFit, New York, USA).
The researchers randomly assigned 51 adults with insomnia, aged 65 to 85 years, to a cognitive training group (n=34) or an active control group (n=17). Both groups completed computer training at home for 8 weeks. For the cognitive training group this involved 21 tasks, each with three levels of cognitive difficulty depending on the patient's ability, whereas for the control group, the tasks did not engage high-level cognitive functioning.
Actigraphy-measured sleep quality following treatment showed a significant difference between the two groups for sleep onset latency and sleep efficiency. Sleep onset latency in patients participating in cognitive training fell from an average 38.42 minutes before intervention to 24.76 afterwards, thereby no longer meeting the criterion for insomnia (>31 minutes). Similarly, sleep efficiency increased from an average 73.54% before treatment to 80.28% afterwards, almost meeting the insomnia exclusion criteria of above 85%.
These improvements were in the higher medium-range in terms of clinical significance, the researchers note in PLoS One.
Cognitive training also had a significant effect on wake after sleep onset and number of awakenings among those receiving cognitive training, whereas within the active control group there were no significant effects observed for any of the sleep variables.
Five cognitive measures - avoiding distractions, naming, general memory, visual memory, and working memory - improved with cognitive training compared with the control intervention.
Notably, while cognitive training resulted in significant improvements in working memory, significant reductions in scores for this cognitive measure were seen in patients in the control groups.
"This finding suggests that individuals with insomnia not only experience some difficulty in preserving their existing cognitive status, but in the absence of systematic training which specifically targets well identified deficits, they might experience steep working memory decline."
Among the control group, this cognitive decline in working memory was associated with an increase in the time required to fall asleep. By contrast, for those receiving cognitive training improved naming was associated with a reduction in wake after sleep onset and the number of awakenings and improvements in avoiding distractions was associated with an increase in nighttime sleep duration.
"Our findings suggest that for older adults suffering from insomnia, cognitive training should be investigated as a promising non-pharmacological option beneficial in the initiation and maintenance of sleep," Haimov and Shatil conclude.
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By Lucy Piper, Senior medwireNews Reporter