This study investigates performance in insomnia patients, comparing it
with performance in normals matched not only on age and sex but also
on education and occupation. There were 26 pairs of insomniacs and nor
mals; and the computer-driven performance battery, lasting about one h
our; was administered three times over the course of a day. In additio
n, an auditory vigilance test was also administered twice. Insomniacs
performed worse than normals on reaction time (they were both slower a
nd more variable), they swayed more on the balance test, and they forg
ot more numbers on the Digit Span Test. There were no significant diff
erences in Digit Symbol Substitution, Divided Attention, and Auditory
Verbal Learning Tests, suggesting that the pattern of deficiencies in
insomnia is different than that in sleep-deprived subjects. When insom
niacs were administered the performance batteries after spontaneously
occurring good or poor nights, little differences in performance were
observed.