Could your personality influence how you rate your sleep quality and quantity?
How often have you thought you didn't sleep a wink all night?
If you aren't getting enough sleep does it affect your performance?
Can you accurately judge how much sleep you have had?
TRIL researchers are trying to answer those questions – and an even bigger one – could our personalities influence the answers to those questions?
It is widely documented that insufficient sleep can affect our performance, specifically how we plan, think and react to situations, in other words our reasoning and judgment. What isn't widely known is that our view of how much sleep we got may actually affect our performance; for instance, we may be subconsciously affecting our performance because we think we are more tired than we actually are.
TRIL researchers are taking a group of 40 older adults, aged 60 years and older and giving them a number of tasks over a week. 20 of the group are insomnia sufferers (identified using the insomnia severity index) and 20 consider themselves to have no sleep issues.
These tasks include:
- wearing an Actiwatch for 7 days and nights. This is a wristwatch which records movement. We don't move much when we sleep so this watch uses this night time inactivity to indicate sleep times. Wearing the watch during the day as well means that TRIL researchers can measure daytime activity also, as this is known to affect sleep at night.
- having a BiancaMed[1] sleep monitor installed in their bedroom for 7 nights. This monitor allows for the recording of movement and respiration, whereas the Actiwatch records wrist movement.
- filling out a sleep diary every day for a week, recording how long they slept for, bedtimes, waketimes, self-rated sleep quality, naps, caffeine intake, sedative intake etc.
- completing tests with a TRIL psychologist the end of the week. These tests will allow TRIL researchers to determine if the participant is suffering from depression, anxiety, stress, what their quality of life is like, if they are lonely or not – and if they are if they are suffering social or emotional loneliness. Important dimensions of personality will also be measured – these are being anxious, a worrier and extraversion. Previous work done by the TRIL Centre has already shown that these measures can predict outcomes of both mental and physical health[2].
In addition they will then do some tests to determine their level of reasoning and judgment e.g. spatial reasoning, logic, etc. The tests have been selected because they specifically target areas of the brain we know to be most affected by a lack of sleep.
At the end the objective measures of sleep, i.e. the actiwatch and sleep monitor results, will be compared to the subjective measures i.e. the sleep diaries, and to the reasoning and judgment tests.
The aim of this study is to determine if someone's personality makes them more or less susceptible to thinking they are getting sufficient sleep, and, if it has an adverse affect, whether interventions can be put in place to help overcome this. The tests they will do with the TRIL psychologist will help to determine their personality type i.e. individuals who are very anxious and worry a lot may tend to report poor health and sleep symptoms more frequently than those who are less anxious, or who worry less. This may mean that, depending on one's personality, participants may misjudge their own sleep.
Also TRIL is looking at whether subjective measures, i.e. sleep diaries, or objective measures, i.e. monitors, are better for determining if someone is genuinely suffering from lack of sleep. We predict that subjective sleep measures may be more strongly associated with executive functioning outcomes than objective sleep measures i.e. thinking one isn't getting enough sleep results in a poorer result, and that this association may be stronger for some personality types than for others.
Studies have shown that if a person can be given evidence they are actually sleeping at night this may help them relax more and thus enjoy more restful sleep.
This project is a joint collaboration between TRIL and BiancaMed.
[1] BiancaMed
[2] McHugh, JE, Casey, AM & Lawlor, BA (2011) Psychosocial correlates of aspects of sleep quality in community-dwelling Irish older adults. Aging & Mental Health, DOI: 10.1080/13607863.2011.562180