Abstract:
The purpose of the current undertaking was to study the electrophysiological
properties of the sleep onset period (SOP) in order to gain understanding into the
persistent sleep difficulties of those who complain of insomnia following mild traumatic
brain injury (MTBI). While many believe that symptoms of post concussion syndrome
(PCS) following MTBI resolve within 6 to 12 months, there are a number of people who
complain of persistent sleep difficulty. Two models were proposed which hypothesize
alternate electrophysiological presentations of the insomnia complaints of those
sustaining a MTBI: 1) Analyses of standard polysomnography (PSG) sleep parameters
were conducted in order to determine if the sleep difficulties of the MTBI population
were similar to that of idiopathic insomniacs (i.e. greater proportion ofREM sleep,
reduced delta sleep); 2) Power spectral analysis was conducted over the SOP to
determine if the sleep onset signature of those with MTBI would be similar to
psychophysiological insomniacs (characterized by increased cortical arousal). Finally,
exploratory analyses examined whether the sleep difficulties associated with MTBI could
be explained by increases in variability of the power spectral data.
Data were collected from 9 individuals who had sustained a MTBI 6 months to 5
years earlier and reported sleep difficulties that had arisen within the month subsequent
to injury and persisted to the present. The control group consisted of 9 individuals who
had experienced neither sleep difficulties, nor MTBI. Previous to spending 3 consecutive
uninterrupted nights in the sleep lab, subjects completed questionnaires regarding sleep
difficulties, adaptive functioning, and personality.
