Perception Research

An infamous example of how one person's perception may differ from others is the black and blue or white and gold dress. You may recall the viral picture where some people described a blue and black striped dress whilst others argued it as white and gold. These are two stark colours, so how can they be confused?

It's because individual differences influence perception. Perception research tries to understand these perceptual processes and the factors influencing them.

• We will start with an introduction to perception, including some of the perception research topics investigated in psychology.
• We will then look at the most commonly used perception research methodology and perception research designs.
• Next, we will shift the focus to learning about research on perception in psychology. The focus will be on studies by Haber and Levin (2001) and Carmichael, Hogan and Walter (1932).

Perception Research Topics

Perception is a subjective process influenced by individual differences, meaning how one person perceives something will be totally different from another.

Because perception involves our interpretation of stimuli, there is a subjective element to remember when considering perception studies.

Psychologists have carried out research to identify factors that influence perception, such as:

• Motivation.
• Culture.
• Schemas.

Perception Research Methodology

One challenging factor surrounding research methods on perception relates to how perception is defined and studied.

The difficulty arises because some of the questions on the topic cannot be empirically tested but instead rely on subjective methods, e.g. the participant describing what they see.

Given the varied nature of the topic perception, various research methods are used to research the topic.

Perception Research Design

Psychologists use several different methods to study perception.

Researchers use experimental methods to test whether manipulating one variable (independent variable) will affect another (dependent variable) whilst controlling external variables (extraneous/ confounding variables). They sometimes involve an 'experimental group' and a 'controlled group'.

The experimental method can involve presenting a sensory stimulus to the participant and recording their response. Some stimuli used to investigate research on perception in psychology are:

• Visual effects and illusions.
• Object recognition.
• Motion detecting.
• Disguising images.

Fig 1. The stairs appear to get narrower the further down people are on the staircase despite each step being the same size; this is an example of an illusion.

Other experimental methods involve instruments whereby the subject's behaviour and reactions are recorded as they undergo a perceptual task, particularly in neuropsychological research on perception.

Research instruments can take the form of surveys, questionnaires, and tests. However, sometimes these methods are not appropriate to use when investigating perception.

What do certain objects look like to you? How would you describe your perception of certain colours? These are examples of introspective questions.

Introspection techniques are not commonly used in psychology because it is widely regarded as unscientific. After all, it relies heavily on subjective opinions. As perception is not something the researcher can directly observe themselves, it is logical for researchers to use introspection techniques.

Perception Quantitative Research: Haber and Levin (2001)

Haber and Levin (2001) investigated size and distance perception. The study involved two experiments.

Experiment 1 investigated how individuals estimate the size of familiar objects. And the researchers used a sample pool of 109 male psychology students at the University of Illinois.

The study used a questionnaire that listed 50 recognisable objects, and each participant was required to estimate the size of each object using the standard US metric system.

The objects were categorised as either token variant objects, meaning the object is available in many sizes or token invariant objects, where the object typically has one standard size.

The results obtained were the following:

• Participants could accurately judge the object's average or typical size.
• There were deviations between 0.36 and 1.26 in token variant objects (they have a less constrained size range, such as Christmas trees).
• There were deviations between up to 0.08 in token invariant objects (they had a constrained size range, such as a bowling ball).

Experiment 2 investigated the distance and size estimations of familiar token variants and token invariant objects (from experiment 1) and the size of unfamiliar objects. To test this, they used a sample of nine male students.

Participants were taken to a field split into four quadrants, three with objects to see and the fourth empty. One had 15 token variant objects, one with 15 token invariant objects, and one with 15 objects of unknown sizes and participants stood in the empty quadrant.

Each participant was instructed to write the size and distance of each object for all three quadrants. Participants were also told to rate how familiar they were with each object using a Likert scale (1 not familiar to 10 very familiar) in addition to giving cognitive estimations of their typical sizes.