Thesis-2012-JordanMPhil.pdf (575.73 kB)
Inconsistencies in the alertness dimensions within measures of sleepiness
thesis
posted on 2012-05-16, 13:36 authored by Katharine JordanThis research investigates whether there is any significant relationship between four
commonly used measures of sleepiness; the Multiple Sleep Latency test (MSLT), the
Psychomotor Vigilance Task (PVT), the Epworth Sleepiness Scale (ESS) and the
Karolinska Sleepiness Scale (KSS) in a group of healthy alert individuals, and to what
extent the individual factors of sex, morningness-eveningness disposition and
personality variables are related to these measures of sleepiness.
Fifty normal sleepers (26 females, 24 males) aged between 21-40 years of age (mean
age 25.18 years) volunteered undergo a standard research MSLT. All participants had
attained 7-8 hours of sleep prior to participation. Between the sleep opportunities they
completed a practice and experimental session of the PVT, the Eysenck Personality
Questionnaire (Adult EPQ-R) and the State-Trait Anxiety Inventory version (STAI
Form Y). Subjective levels of sleepiness were collected using the KSS before each
sleep opportunity of the MSLT, and either side of the PVT sessions. The Horne-
Ostberg Morningness-Eveningness disposition questionnaire and ESS scores were
collected prior to the testing day.
There was no significant correlation between the measures of sleepiness using the
whole data set. Relationship between the measures of sleepiness was not improved by
time of day. When the data was split by latency on the MSLT, a significant negative
correlation was found between the MSLT and ESS, but only in nine participants. Sex
of the participant was only significantly related to the ESS. The MSLT was the only
measure of sleepiness found to be significantly related to the
morningness/eveningness disposition of the participants. Personality characteristics
were not significantly related to the ESS or PVT. A significant positive relationship
between neuroticism score and latency on the MSLT was found when those
participants who did not sleep in the MSLT were excluded from analysis. Scores on
the KSS were significantly related to levels of neuroticism, state and trait anxiety and
scores on the Lie scale of the EPQ.
It is concluded that although these measures of sleepiness are commonly used
together, they do not have a significant relationship to each other in a group of healthy
alert individuals. This suggests that each measure of sleepiness may be measuring a
different component of the alertness-sleepiness spectrum, therefore no one measure
can be relied upon to replace another in the measurement of alertness or sleepiness.
Some significant relationships between the alertness dimensions of certain measures
of sleepiness and the individual differences within the participant group have been
revealed, yet as no single individual difference measured in this investigation was
significantly related to all of the measures of sleepiness, it is unlikely that these
particular individual differences in the participant group are solely responsible for the
inconsistencies in the alertness dimensions of these measures of sleepiness. Further
investigation is required in order to further establish why there are inconsistencies in
the alertness dimensions of these measures of sleepiness.
History
School
- Sport, Exercise and Health Sciences
Publisher
© K.E. JordanPublication date
2012Notes
A Master's Thesis. Submitted in partial fulfilment of the requirements for the award of Master of Philosophy of Loughborough University.Language
- en
Qualification name
- MPhil
Qualification level
- Masters