Pre-Sleep Arousal Scale (PSAS)
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What is the Pre-Sleep Arousal Scale (PSAS)
Falling asleep can feel impossible when your mind races with worries or your body refuses to relax, turning bedtime into a restless ordeal. For many, this pre-sleep alertness—mental chatter or physical tension—stretches minutes into hours, leaving rest out of reach. As a Sydney psychologist, I’ve helped countless clients navigate this struggle, where pre-sleep arousal transforms night into a challenge rather than a refuge. The Pre-Sleep Arousal Scale (PSAS) is a 16-question tool I use to measure these disruptive states, pinpointing the thoughts and sensations that fuel insomnia.
Developed by sleep experts decades ago, the PSAS is a validated assessment—meaning it’s been thoroughly tested for accuracy—to uncover what keeps you awake. In my Sydney practice, I’ve seen it reveal hidden triggers clients didn’t notice, like a looping to-do list or a racing pulse. It’s not a cure by itself, but a diagnostic step backed by science. Below, explore its purpose and how it can guide you toward better sleep with support from a Sydney psychologist
What Is the PSAS and Why It Matters
The Pre-Sleep Arousal Scale (PSAS), first introduced by Nicassio and colleagues in 1985, is a cornerstone in sleep psychology, designed to capture two distinct but intertwined aspects of insomnia: cognitive arousal—think racing thoughts, worry, or replaying the day—and somatic arousal, like a pounding heart, tight muscles, or shallow breathing. These aren’t mere annoyances; research shows that high levels of pre-sleep arousal directly delay sleep onset, often by amplifying anxiety or physical restlessness right when calm is needed most (Wicklow & Espie, 2000). This dual focus makes the PSAS uniquely effective—it doesn’t just ask if you’re awake; it digs into why, splitting the experience into manageable pieces.
In my Sydney practice, I’ve used the PSAS to help clients uncover these hidden triggers, from the mental spiral of “Will I sleep tonight?” to the physical jolt of a racing pulse. For those whose arousal stems from worry—about sleep, the next day, or beyond—it pairs well with techniques like Worry Time, which I’ve detailed elsewhere on this site to manage overthinking before bed. The PSAS isn’t about instant solutions or superficial fixes; it’s a structured way to understand what’s fueling your insomnia, backed by decades of sleep science and my own clinical observations. By identifying these patterns, it lays the groundwork for real, lasting change when paired with professional guidance.
Take the PSAS Assessment
Below, you’ll find 16 statements split evenly: eight about your mind before sleep—like racing thoughts or worry—and eight about your body, such as a pounding heart or tense muscles. Rate each from 1 (not at all) to 5 (extremely) using the sliders, reflecting how you feel as you try to fall asleep. If you score 4 or higher—indicating significant arousal—you’ll receive four evidence-based tips tailored to that item: two to calm your thoughts, two to ease physical tension. These aren’t random suggestions; they’re drawn from Cognitive Behavioral Therapy for Insomnia (CBT-I), a proven framework I use to help clients shift their sleep experience.
Interpreting Your PSAS Score
After rating the 16 PSAS items, your score—ranging from 16 to 80—shows how much pre-sleep arousal affects you. Add up your points: 1 to 5 per question, with higher totals signaling stronger barriers to sleep. A psychologist might flag scores above 48 (averaging 3+) as significant—say, if ‘Worry about falling asleep’ hits 5, it’s amplifying your nighttime stress. Scores of 4 or 5 on any item trigger tips, but the total paints the bigger picture. Below 32? Arousal’s less of an issue, though sleep troubles might still linger. With our online version above we are more concerned about individual items rather than the total score.
Research links high PSAS scores to delayed sleep—those averaging 4+ can take 30+ minutes longer to drift off (Wicklow & Espie, 2000). In my Sydney practice, I’ve seen clients with scores near 60 cut that time with targeted strategies. It’s not a diagnosis—just a map. If cognitive items dominate (e.g., 40+ of your total), overthinking’s the culprit; if somatic scores lead, your body’s on edge. Either way, a psychologist can refine this into a plan—explore insomnia treatment below if scores stay high after trying your tips
Validity and Reliability of the PSAS
The Pre-Sleep Arousal Scale (PSAS) isn’t just a basic questionnaire—it’s a carefully designed tool that sleep experts trust, supported by years of research. It was created by Nicassio and his team in 1985 and tested to make sure it works well. One way they checked this is with something called Cronbach’s alpha, which is like a score showing how dependable the tool is. For the PSAS, this score is between 0.85 and 0.90—pretty high, close to a perfect 1. This means the 16 questions all do a good job of measuring the same thing: how worked up your mind and body are before sleep.
Another test is called test-retest reliability, which is about 0.80 for the PSAS. This is a way to see if the tool gives steady results over time. If you answer the questions today and again in a few weeks, and your sleep habits haven’t changed, your scores should be almost the same—showing it’s a reliable picture of what’s happening at bedtime. The PSAS also connects well with other insomnia tools, like the Insomnia Severity Index (ISI). They match up with a strength of 0.65, meaning it’s good at picking out the thoughts and feelings that keep you awake, just like those other tests do (Morin et al., 2006).
In my Sydney practice, I depend on its accuracy to find out what’s stopping your sleep—whether it’s a busy mind or a tense body, it gets right to the point. A psychologist uses this steady performance to watch how you’re doing; as those restless feelings lessen, sleep often gets better. It’s not foolproof—things like stress or your mood might slightly change your answers—but it’s a strong first step for most people. Curious how it fits into insomnia treatment? It’s a key part of Cognitive Behavioral Therapy for Insomnia (CBT-I), helping create plans to calm your nights. See its roots below and why it’s a go-to tool!
PSAS vs Other Sleep Tools
The PSAS stands out by targeting pre-sleep arousal—mental and physical—unlike broader tools. The Athens Insomnia Scale (AIS) measures overall sleep quality, while the Epworth Sleepiness Scale (ESS) tracks daytime fatigue. The PSAS zeroes in on bedtime: 8 mind questions (e.g., ‘Worry about falling asleep’) and 8 body ones (e.g., ‘Tense muscles’). The Sleep Hygiene Index (SHI) checks habits like screen time, but PSAS digs into your state as you lie down.
Compare it to the ISI: that tool grades insomnia severity (0–28), not why you’re awake. PSAS scores (16–80) pinpoint triggers; a psychologist might pair it with a sleep diary to map patterns. Studies show high PSAS scores predict sleep delays of 30+ minutes (Wicklow & Espie, 2000)—perfect for CBT-I tweaks.
What Next?
Once you’ve taken the PSAS, review your tips—small shifts in mind and body can reduce pre-sleep arousal. Research confirms calming strategies cut sleep latency (Morin et al., 2006), but lasting improvement often requires more. In my Sydney practice, I’ve helped clients refine these steps in person, combining tools like the PSAS and Worry Time (sometimes known as Worry Postponement) with personalized plans. If sleep remains elusive, it may signal deeper patterns to address. Book a session below to take your next step toward rest.
Explore More Insomnia and Sleep Tools
Investigate other validated measures to assess insomnia, sleep quality, sleep hygiene, and factors like daytime sleepiness or beliefs about sleep. Track patterns with our sleep diary or visit our assessment hub for a full overview of insomnia assessment.
- Insomnia Severity Index (ISI) – Gold standard self-report tool for insomnia severity over two weeks.
- Pittsburgh Sleep Quality Index (PSQI) – Assesses overall sleep quality and disturbances over a month.
- Athens Insomnia Scale (AIS) – Broad sleep quality, not just insomnia.
- Sleep Condition Indicator (SCI) – Screens insomnia per DSM-5 with a focus on sleep satisfaction.
- Epworth Sleepiness Scale (ESS) – Guages daytime sleepiness across eight everyday situations.
- Sleep Hygiene Index (SHI) – Identifies sleep-disruptive habits and behaviours affecting rest.
- Dysfunctional Beliefs and Attitudes about Sleep (DBAS-16) – Probes unhelpful beliefs influencing sleep difficulties.
- Pre-Sleep Arousal Scale (PSAS) – Measures cognitive and physical arousal before bedtime.
- Assessment Hub: Central hub for all sleep and insomnia measures.
- Sleep Diary: Records daily sleep habits for personalised insights.
References for the Pre-Sleep Arousal Scale (PSAS)
Morin, C. M., Bootzin, R. R., & Buysse, D. J. (2006). Psychological and behavioral treatment of insomnia: Update of the evidence. Sleep, 29(11), 1398–1414. https://doi.org/10.1093/sleep/29.11.1398
- Description: This review synthesizes evidence on CBT-I techniques, including strategies like those in the PSAS tips, demonstrating reduced sleep latency and enhanced rest across multiple studies.
Nicassio, P. M., Mendlowitz, D. R., & Fussell, J. J. (1985). The phenomenology of the pre-sleep state: The development of the pre-sleep arousal scale. Behaviour Research and Therapy, 23(3), 263–271. https://doi.org/10.1016/0005-7967(85)90004-X
- Description: This foundational study developed the PSAS, validating its ability to measure cognitive and somatic arousal as key contributors to insomnia, shaping its clinical use.
Wicklow, A., & Espie, C. A. (2000). Intrusive thoughts and their relationship to actigraphic measurement of sleep. Journal of Psychosomatic Research, 48(6), 557–564. https://doi.org/10.1016/S0005-7967(99)00136-9
- Description: This research links elevated pre-sleep arousal, particularly intrusive thoughts, to objectively measured delays in sleep onset, reinforcing the PSAS’s relevance in insomnia assessment.
