Perception studies

AIM: to find out if food deprivation affects the perception of food

METHOD: 2 groups of students - 1 deprived of food for 20 hours, 1 control (not hungry) - both shown 4 slides of meals for 15 seconds - picture shown again but dimmer - participants had to make the picture the same brightness as before

RESULTS: participants who were deprived of food perceived the photo as brighter - control group didnt perceive it as brighter

CONCLUSION: being deprived of food increased perceptual sensitivity - hunger is a motivating factor

EVALUATIONS: similar studies show similar results - increases validity of results. unethical to deprive people of food - goes against BPS guidelines

AIM: to find out whether an ambiguous figure was seen differently depending on context

METHOD: independent groups - participants given sequence of letters or numbers with same ambiguous figure in middle (could be seen as either 13 or B) - asked to draw what they saw

RESULTS: those who saw letters more likely to draw figure as B - those who saw numbers more likely to draw figure as 13

CONCLUSIONS: expectations of what the figure represented was affected by the context which the figure was presented in

EVALUATIONS: STRENGTH - real life application - helps to explain why people sometimes make serious errors on real life tasks. WEAKNESS - artificial task - ambiguous figures are designed to trick perception = results lack validity. WEAKNESS - independent groups - differences in perception could be due to participant variables rather than expectations

AIM: to find out whether people from different cultures/educational backgrounds perceived depth cues in 2D images differently

METHOD: showed 2D images to South Africans - native black people who were schooled/unschooled & white people of European descent who were schooled/unschooled - ppts had to say which animal the man was pointing the spear at - was pointing at elephant & antelope but depth cues made it seem like was pointing at antelope

RESULTS: both black&white schooled ppts more likely to perceive depth than unschooled ppts & white schooled ppts more likely to perceive depth than black schooled ppts

CONCLUSION: people from diff cultural/educational backgrounds use depth cues differently & have diff perceptual set. supports Gregory's theory - depth cues are learned

EVALUATIONS: language barrier = instructions might not have made sense = affects validity of results. some ppts may have been confused when seen drawings on paper = representation affects results

AIM: to see whether things that cause anxiety are less likely to be noticed than things considered emotionally neutral

METHOD: 8 male & 8 female students shown neutral & taboo words on a screen - after each word ppts had to say it out loud - amount of emotional arousal measured using GSR machine

RESULTS: ppts took longer to say the taboo words compared to neutral words. taboo words caused more change in GSR than neutral words

CONCLUSION: emotion affects perceptual set - perceptual defence is used by brain when confronted with words that are offensive/cause anxiety

EVALUATIONS: objective method of measurement - scientifically based - less bias than rating scales. embarrassment not defence - delayed response could be due to awkwardness saying the word - awkwardness could've been an extraneous variable