Psychology says people who need the same pillow position every night may rely on sensory predictability

For some people, bedtime is not complete until the pillow is positioned in exactly the right place. It may need to face a particular direction, sit at a familiar height or support the head in precisely the same way it did the night before. Someone else might see this as an unnecessary preference, but the person may experience a noticeable difference when the pillow is moved. Psychology suggests that repeated sensory experiences can become associated with comfort, familiarity and expectations about what comes next. The behavior does not automatically indicate anxiety, obsessive-compulsive disorder or a sensory-processing condition. Instead, a preference for the same pillow position may sometimes reflect a broader psychological tendency to seek predictability, particularly during a transition as important as falling asleep.

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