PSYC 2390 Lecture Notes - Lecture 3: Everytime, Absolute Threshold

• School: University of Guelph
• Department: Psychology
• Course: PSYC 2390
• Professor: Lana Trick

Document Summary

Lecture 3 sept 11th: how is absolute threshold measured, method of limits. E. g. intensity of light 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10: method of adjustments. Participant adjusts know until they can see the light/vice versa (or until they can hear the sound, etc. : method of constants. 5-9 different intensities; 100 trials of each. E. g. 6 different intensities, 600 trials & randomize order. Graph percentage of time the person can see/hear/etc each intensity level. Look at the intensity the person can see 50% of the time. Absolute threshold = intensity seen 50% of the time. Discrimination: telling the difference between two things. Jnd: just noticeable difference = difference threshold. Always need 2 stimuli (standard & comparison stimulus) Your ability to perceive contrast (difference between things) Smokers: carbon monoxide increases the difference threshold. Co makes it harder for you to see differences in brightness (need large difference in brightness to see).