Karyn O'Keeffe

Dr Karyn O'Keeffe has been working in sleep for over 10 years now. She started her career as a Clinical Sleep Physiologist at WellSleep, University of Otago Wellington, where she diagnosed and initiated treatment in those with sleep disorders. After five years of rotating shift work, including nights, she was keen for a new challenge, so found herself in two half-time roles at two universities – at both WellSleep and the Sleep/Wake Research Centre – while completing her PhD (yes, insane). A few years ago, she moved away from a clinical role entirely and now works full-time as a Research Fellow at the Sleep/Wake Research Centre at Massey University.

Measuring sleep: The squiggles explained! (Part 2) - Sleep on it

Apr 07, 2011

In a previous post, I provided an overview of the stages of human sleep.  But how do we determine what stage of sleep a person is in? The current gold standard for objectively measuring sleep is called polysomnography or PSG. This mouthful is derived from the Greek poly meaning ‘many’, somnus meaning ‘sleep’ and graphein meaning ‘to write’.  Polysomnography allows us to record a wide range of physiologic signals during a sleep period.  At the simplest level, we will record signals that allow us to stage human sleep, but in addition we often measure signals such as heart rate, breathing (effort and airflow), muscle movement, oxygen saturation, carbon dioxide levels and behaviour (via video input).  Each recorded signal requires a sensor, or several sensors, often making this quite an overwhelming experience for a patient or research participant. To be … Read More

Measuring sleep: The squiggles explained! (Part 1) - Sleep on it

Mar 23, 2011

I’m sure you’ve been wondering all week about the strange ‘squiggles’ in my blog banner.  Well, perhaps not, but the sleep geek in me hopes that at least one of you has.  My blog banner has a segment of an electroencephalogram (EEG) or ‘brain waves’.  This is a recording of my EEG, in fact. At this point in the night, I am in Stage 2 sleep.  Each night when we go to sleep, we will experience non-REM sleep and REM sleep.  Non-REM sleep (also written as NREM sleep) has been further categorised as Stages 1 through 4.  A bit of sleep history… The concept of sleep stages was first postulated in 1937 by Loomis et al.  This concept went through several iterations in the following decades.  However, it was Aserinky and Kleitman’s groundbreaking discovery of REM sleep in … Read More

Caffeine affects your sleep. No ifs, no buts. - Sleep on it

Mar 11, 2011

Caffeine is one of the most commonly consumed psychoactive substances.  It is everywhere, in coffee, black tea, green tea, soft drinks, energy drinks, chocolate and over-the-counter medications.  We are all aware that caffeine is a stimulant; however, few of us appreciate that it can have a significant impact on our sleep. Do any of these statements ring a bell? Myth: Coffee has no effect on me.  I can have a coffee right before bed and have no problem going to sleep. Fact: If you ingest enough caffeine you may have trouble getting off to sleep but in a regular consumer this is not usually where the damage is done.  Caffeine adversely affects the quality of your sleep. Myth: I don’t drink much caffeine.  I drink tea. Fact: Brewed products are the most variable in caffeine content, … Read More

Why blog about sleep? - Sleep on it

Mar 09, 2011

Brigid Gallagher’s recent blog post on a typical conversation at a social function had me smiling.  I’m no archaeologist.  In fact, the little I know about archaeology, I’ve probably gleaned from Indiana Jones (gasp!).  Yet, there seemed to be so many parallels to the conversations Brigid has experienced and my own, that I couldn’t help but feel like we were on completely the same page.  Perhaps I’ve misrepresented Brigid here, but my conversations have also had a quiet undertone of ‘Seriously, you waste time every day studying that?’ Until recently, I spent a good proportion of my working week as a Clinical Sleep Physiologist, a fancy way of saying that I worked in a clinical sleep laboratory diagnosing and treating those with sleep disorders.  Most people are fascinated by this.  Questions pour out about sleep and sleep disorders.  … Read More