Perceptual set = the tendency for our brain to notice certain aspects of the environment more than others.
Culture = the social world that surrounds you.
Perceptual set and culture - Aim
Hudson aimed to find out whether people from different cultural/educational backgrounds perceived depth cues in 2D images differently.
Perceptual set and culture - Method
He showed 2D drawings to participants in South Africa – native black people who were either schooled or unschooled; and white people of European descent who were either schooled or unschooled.The participants had to say which animal the man was trying to spear. The spear was pointing at an elephant and an antelope but depth cues suggested it was actually being aimed at the antelope.
Perceptual set and culture - Results
Despite the picture using height in the visual field and relative size to indicate depth, many believed the spear was pointing to the elephant. Both black and white schooled participants were more likely to perceive depth than unschooled participants. White schooled participants were more likely to perceive depth than black schooled participants.
Perceptual set and culture - Conclusion
People from different cultural/educational backgrounds use depth cues differently and have a different perceptual set. This supports Gregory’s theory as it shows that depth cues are learned.
Perceptual set and culture - Evaluation weakness
Cross-cultural research
One weakness is the instructions may not make sense. The language barrier means translations of the method may have been unclear. This will therefore affect the validity of the results.
Perceptual set and culture - Evaluation weakness
Problems with the method.
A weakness is that some of the participants may have been confused by seeing drawings on paper. When more familiar materials such as cloth were used they gave different answers. This shows representation affects results.
Perceptual set and culture - Evaluation weakness
Poor design.
One weakness is that the research is from a long time ago and may be poorly designed. Early cross-cultural studies of perception often did not include things like proper control groups. This caused the results of cross-cultural differences in perception to lack validity.
Perceptual set and emotion
The tendency for our brain to notice things that are exciting, interesting or unusual. But also block things that make us anxious or we find threatening.
Emotion - Aim
McGinnies wanted to see whether things that cause anxiety are less likely to be noticed than things that are emotionally neutral.
Emotion - Method
Eight male and eight female students were shown neutral and offensive ‘taboo’ words flashed on a screen. After each word was shown participants had to say it out loud. The amount of emotional arousal was measured through their galvanic skin response (GSR) which records electrical changes in the skin.
Emotion - Results
Participants took longer to say offensive words like ‘bitch’ and ‘penis’ than neutral ones like ‘apple’ and ‘dance’. Taboo words produced bigger changes in the GSR than neutral words.
Emotion - Conclusion
This shows that emotion affects perceptual set. Perceptual defence is used by the brain when confronted with words that are offensive or cause anxiety.
Emotion - Evaluation strength
Objective measurement
One strength of this study is that it used an objective measurement of emotion. A scientific method was used – the galvanic skin response – to test biological anxiety responses. This produces results that are less open to bias than, for example, rating scales.
Emotion - Evaluation weakness
Embarrassment not defence.
One weakness is that delayed recognition may be more to do with embarrassment. Participants may have hesitated in giving their response as they were uncomfortable repeating rude words in a study. This suggests that awkwardness may have been an extraneous variable.
Emotion - Evaluation weakness
Contradictory results.
One weakness of studies in this area is that the results are contradictory. This is because sometimes they suggest we are more likely to notice emotional material, and sometimes we are less likely. This makes it difficult for psychologists to draw firm conclusions.
Perceptual set and motivation
The force that drives your behaviour (motivation) can affect how you perceive things in the environment. Wanting something can increase its attractiveness.
Motivation - Aim
Gilchrist and Nesberg aimed to find out if food deprivation affects the perception of pictures of food.
Motivation - Method
Two groups of students: one group deprived of food for 20 hours and a control group (not hungry). Students were shown four slides, each one showing a meal. The slide was displayed for 15 seconds. The picture was shown again, but dimmer, and participants had to adjust the lighting to make it look the same as it did before.
Motivation - Results
Participants perceived the food as brighter the longer they were deprived of food. The control group (who were not deprived of food) didn’t perceive the food as brighter.
Motivation - conclusion
Being deprived of food increased perceptual sensitivity. This shows that hunger is a motivating factor that affects the way food-related pictures are perceived.
Motivation - Evaluation strength
Support from similar studies.
One strength is that similar studies have found similar results. Sanford deprived participants of food and showed them ambiguous pictures. The longer they were deprived of food the more likely they were to see food. This increases the validity of the Gilchrist and Nesberg results.
Motivation - Evaluation weakness
Ethical issues.
A problem with studies in this area is that they are unethical. This is because depriving participants of food and water could cause them to feel uncomfortable. This is an issue as you should not do this in psychological research.
Motivation - Evaluation weakness
Not like everyday life.
A problem with the study is that it was not like everyday life. Participants were asked to judge pictures of food rather than real food. This makes it harder to apply the results to situations in the real world.
Perceptual set and expectation
The belief about what is likely to happen based on past experiences can affect how much we attend to or notice things in the environment.
Expectation - Aim
Bruner and Minturn aimed to find out whether an ambiguous figure was seen differently if the context of the figure was changed.
Expectation - Method
An independent groups design was used where participants were either presented with a sequence of letters or a sequence of numbers with the same ambiguous figure in the middle. The ambiguous figure could be seen as either the letter B or as the number 13. Participants had to report and also draw what they saw.
Expectation - Results
Those who saw a sequence of letters were more likely to report the figure as being the letter B and tended to draw a 'B'. If shown numbers they were more likely to say it was the number 13 and drew a '13'.
Expectation - Conclusion
This shows that expectation of what the figure represented was affected by the context that the figure was presented in.
Expectation - Evaluation weakness
Artificial task
One weakness of the study is that it used an artificial task. An ambiguous figure is designed to trick perception. This makes the results lack validity.
Expectation - Evaluation weakness
Independent group designs.
One weakness relates to the fact that there were individual differences between groups. This is because an independent groups design was used. This is an issue as differences in perception between the groups may have been due to participant variables rather their expectations.
Expectation - Evaluation strength
Real-life application.
One strength of this study is that it has real-life application. It can explain errors that people make as the results suggest that expectations can influence perception. This helps to explain why people make sometimes serious mistakes on tasks in the real world.