PSYO 111 Lecture Notes - Lecture 4: Detection Theory, Absolute Threshold, Neural Adaptation

• School: UBC Okanagan, UBC OK
• Department: Psychology
• Course: PSYO 111
• Professor: Shirley Hutchinson

Document Summary

Perception: organization, identification, and interpretation of a sensation in order to form a mental representation. Transduction: sensors in the body convert physical signals from the environment into encoded neural signals sent to the cns. Psychophysics: methods that measure the strength of a stimulus and an observer"s sensitivity to that stimulus. (tries to objectify) Measuring thresholds: determining how much physical energy is required to become aware of a sensation. Absolute threshold: minimal intensity needed to detect a stimulus in 50% of the trials. Just noticeable difference: minimal change in a stimulus that can just be barely be detected - not a fixed quantity (varies every time with each person). Weber"s law: jnd of a stimulus is a constant proportion (1 vs. 2 lbs = noticeable; 20 vs. 20. 1 lbs = undetectable). Sensory adaptation: sensitivity to prolonged stimulation tends to decline overtime as organism adapts to situation.