In
physiology,
psychology, or
psychophysics
Psychophysics quantitatively investigates the relationship between physical stimuli and the sensations and perceptions they produce. Psychophysics has been described as "the scientific study of the relation between stimulus and sensation" or, m ...
, a limen or a liminal point is a
sensory threshold
In psychophysics, sensory threshold is the weakest stimulus that an organism can sense. Unless otherwise indicated, it is usually defined as the weakest stimulus that can be detected half the time, for example, as indicated by a point on a probabi ...
of a physiological or psychological response. Such points delineate boundaries of perception; that is, a limen defines a sensory threshold beyond which a particular stimulus becomes perceivable, and below which it remains unperceivable.
Liminal, as an adjective, means situated at a sensory threshold, hence barely perceptible. Subliminal means below perception.
The
absolute threshold is the lowest amount of sensation detectable by a sense organ.
See also
*
Just noticeable difference (least perceptible difference)
*
Threshold of pain, the boundary where perception becomes pain
*
Weber–Fechner law (Weber's law)
References
Physiology
Perception
{{Neuroscience-stub