Experiment Methods & Perception

Quasi-Experiments

studies in which the researcher lacks complete control over the conditions and/or variables

Ceiling Effect

all the scores are squeezed together at the high end

Floor Effect

all the scores cluster at the low end

Physiological Data

information about a person derived from measurement of biological structures and processes

Electroencephalogram (EEG)

record of the electrical activity of the brain

Shows physiological data

Event-Related Potential (ERP)

an averaged measurement of EEG's that is the result of a repeatedly presented stimuli

Shows physiological data

PET & fMRI

produce images that depict changes in neural activity in each area of the brain by measuring changes in blood flow

Dualist Perspective (Descartes)

physical (body) and mental (mind) separate

interaction = human experience

Monist Perspective (Hobbes)

physical processes ⟶ mental experiences

no "mind" - only brain!

Naïve Realism

1:1 relationship between sensations in the physical world and perceptions in our brain

what you see is what you get

Naïve Realism: Problems

Illusions and things humans can't sense

Top-Down Processing

prior knowledge, expectations, context to identify something

Bottom-Up Processing

the analysis of the smaller features to build up to a complete perception

Gestalt Psychology

the whole is greater than the sum of its parts

Ex: Mr. Potato Head

Principles of Perceptual Organization

Proximity

Simplicity

Continuity

Closure

Grouping Principles: Proximity

nearby figures are grouped together

Grouping Principles: Simplicity

we perceive the basic form of the stimulus

Grouping Principles: Continuity

perceive continuous patterns

Grouping Principles: Closure

Brain tends to fill in gaps in order to perceive complete forms

Palmer (1975): Scene Schemas

knowledge of what is typically found in a setting or a scene

Greebles (Gauthier, et al., 1999)

FFA responds to Greeble faces = human faces

physiological evidence

Environment Recognition Blakemore & Cooper (1970)

Kittens raised in horizontal or vertical environment

Neurons develop to respond best to that direction

Effects of Action on Perception

Traditional Approach: create mental representation of something in the environment

Action-based Approach: guide actions in the environment for survival

Striate Cortex to Temporal Lobe

What pathway

identification of objects

Striate Cortex to Parietal Lobe

where pathway

location of objects

Size Perception Witt & Proffitt (2005)

better players judge ball to be bigger than novice players