The methods used to obtain and depict sleep data shape our understanding of
sleep as a phenomenon. The standard criteria for describing sleep were dev
eloped in the late 1960s. These criteria, which were established on the bas
is of the polysomnographic equipment available at that time, called for the
division of sleep into stages according to depth: the visual depiction of
these stages led to the now widely accepted concept of "sleep architecture.
" Although the sleep architecture model remains useful, the technology that
provided the model's framework for understanding sleep has been superseded
by computer-assisted systems for recording and analyzing sleep that may al
low us to acquire data on sleep that were unobtainable with older equipment
. Future gathering and depiction of sleep data, regardless of the recording
and assessment methods used, should minimize disruption of sleep during st
udy allow for computerized analysis of sleep parameters, and describe the d
ata from the perspective of;:he effect that sleep and the problems surround
ing it have on daytime functioning.