Cognitive Psychology: Chapter 3

Perception

Conscious experience from stimulation of the senses

• Involves invisible, complex processes

Can change based on added information

Inverse Projection Problem

Task of determining the object that caused a particular image on the retina

Why are perceiving machines hard to make?

• Hidden/blurred objects aren’t detected

• High-level info for context clues would need to be programmed

• Viewpoint invariance: the ability to recognize an object from different viewpoints

Top-down processing

Processing from knowledge/expectations

• Originates in the brain

• Assuming an object in a kitchen is a knife since it fits the scene

Bottom-up processing

Environmental energy stimulates electrical impulses from the eye to the brain

• Looking at a painting and studying the landscapes, colors, etc. to determine the scene

Speech segmentation

Process of perceiving words within the continuous flow of the speech signal

• Knowing the end of one word and the start of the other

Transitional probabilities

The likelihood that one speech sound will follow another

• Statistical learning: process of learning about transitional probabilities, in children as young as 8

Helmholtz’s theory of unconscious interference

• Likelihood principles: we perceive the object most likely to cause a pattern of stimuli

• Unconscious interference: some perceptions are the result of unconscious assumptions about the environment

Gestalt principles of organization

• Apparent movement: illusion of movement when stimuli are flashed one after another

• Whole of perception is larger than single sensations grouped together

Good continuation principle

Straight/curved lines are viewed as belonging together when connected

• Lines are seen as following the smoothest path

Good figure/simplicity principle

Every stimulus is seen so that the resulting stimulus as simple as possible

Similarity principle

Similar things appear grouped together

Regularities of the environment

• Physical regularities: man-made environments have more vertical/horizontal lines than angular ones

  • Oblique effects: vertical/horizontal orientations are perceived more easily than slants

Light-from-above regularity

We assume light is coming from the top down into a space

Semantic regularities

Characteristics/functions associated with different scenes

• Assuming eating in the ktichen

Scene schema

Knowledge about what is likely to be in a specific scene

Bayesian influence

An estimate of an outcome’s probability is based on two factors

• Prior: initial belief about an outcome’s probability

• Likelihood: extent to which evidence is consistent with the outcome

Ventral/what pathway

Neural pathway from the occipital to the temporal lobe that helps with object perception/recognition

Dorsal/where pathway

Neural path from visual cortex to parietal lobe that help with object location

Mirror neurons

Help replicate actions we see others do

Sensory receptors

Specialized cells that receive and convert physical information into a neural signal

Sensation

Stimulation of sensory organs

Perception

Processing and interpretation of sensory inputs

Eye receptors

• Cone-mediated: finer, color details

• Rod-mediated: black and white vision

Blakemore and Cooper’s Cat Experiment

Kittens respond to moving vertical sticks, but ignored horizontal objects

• Example of experience-dependent plasticity

Affordances

Potential actions individuals perceive when interacting with objects in their environment

• aka clues about how an object should be used