Chapter 4- Sensation And Perception Flashcards
Sensation
Process of detecting, converting, and transmitting raw sensory information from the external and internal environments to the brain
Perception
Process of selecting, organizing, and interpreting sensory information into understandable patterns
Transduction
Converting a receptor’s energy into neural impulses that are sent on to the brain
Coding
Converting sensory inputs into different sensations
Sensory reduction
Filtering and analyzing incoming sensations before sending neural messages on to the cortex
Psychophysics
Studies the link between physical characteristics of stimuli and our sensory experience of them
Absolute Threshold
Minimum amount of a stimulus that an observer can reliably detect
Difference threshold
Minimal difference needed to notice a stimulus change
Aka Just Noticeable Difference
Subliminal Perception
Perceiving something without conscious awareness
doesn’t necessarily cause or change actions
Sensory Adaptation
Repeated or constant stimulation decreases the number of sensory messages sent to the brain which causes decreased sensation
Gate-Control Theory
Theory that pain sensations are processed and altered by mechanisms within the spinal cord
Damaged tissue opens the gate, counter pressure closes the gate
Pain is a mix of biological and psychological factors
Endorphins
Neurotransmitter that acts in the same way as morphine by inhibiting pain perception and closing the gate
Substance P
Neurotransmitter that opens the pain gate
Wavelength
The distance between successive peaks
Long wavelength/low frequency- reddish colours, low sounds
Short wavelength/high frequency- blueish colours, high sounds
Wave Amplitude
The height from peak to trough
Low amplitude/low intensity- dull colours, soft sounds
High amplitude/high intensity- bright colours, loud sounds
Range of wavelengths
The mixture of waves
Small range/low complexity- less complex colours and sounds
Large range/high complexity- complex colours and sounds
Fovea
Tiny pit in the centre of the retina filled with cones; responsible for sharp vision
Blind Spot
Point at which the optic nerve leaves the eye; contains no receptor cells for vision, thus creating a blind spot
Accommodation
Automatic adjustment of the eye which occurs when muscles change the shape of the lens so that it focuses light on the retina from objects at different distances
Retina
Light sensitive inner surface of the back of the eye, which contains the receptor cells for vision
Rods
Visual receptor cells in the retina that detect shades of gray and are responsible for peripheral vision
Most important in dim light and at night
Cones
Visual receptor cells, concentrated near the centre of the retina, responsible for colour vision and fine detail
Most sensitive in brightly lit conditions
Place Theory
Explains that pitch perception is linked to the particular spot on the cochlear’s basilica membrane that is most stimulated
Frequency Theory
Explains that pitch perception occurs when nerve impulses sent to the brain match the frequency of the sound wave
Olfaction
Sense of smell
Pheromones
Compounds found in body scents that may affect various behaviours
Gustation
Sense of taste
5 Taste Sensations
Sweet, sour, salty, bitter, uami (delicious)
Skin
Tactile sense- uses a variety of receptors located in different parts of the skin to detect pain, temperature, fine touch, and pressure
Vestibular
Sense of body movement and position, also called the sense of balance
Located in the inner ear, composed of the vestibular sacs and the semicircular canals
Kinesthesis
Sensory system for detecting body posture, orientation, and movement of individual body parts
Kinesthetic receptors are found throughout the muscles, joints, and tendons of the body
Selective Attention
Filtering out and attending only to important sensory messages
Feature Detectors
Specialized neurons that respond only To certain sensory information
Habituation
The brains reduced responsiveness to unchanging stimuli
Gestalt Principles
Emphasizes the importance of organization and patterning in enabling us to perceive the whole stimuli
Figure Ground Principle
Gestalt
We are able to distinguish objects from their surroundings
Proximity Principle
Gestalt
We group together objects that are physically close
Continuity Principle
Gestalt
Objects that continue a pattern are grouped together
Closure Principle
Gestalt
The tendency to see a finished unit from and incomplete stimulus
Similarity Principle
Gestalt
Similar objects are grouped together
Binocular Depth Cues
Retinal disparity- images on retina can be in different places depending on the distance of the image
Convergence- the turning in of your eyes, the strain of which help your brain interpret distance
Size Constancy
We are able to look past obvious size disparities because we know from experience the general size of things
Shape Constancy
As an object rotates or moves it changes shale but we can still perceive it as the same shape
Colour and Brightness Constancy
Although there are shadows and highlights, we perceive constancy in the colour
Trichromatic Theory
Found that there are 3 primary colours (red, blue, and green) that can be combined to form all colours
Opponent process theory
Hering’s theory states that colour perception is based on three systems of colour opposites
Blue yellow, red green, black white
Perceptual Adaptation
The brains ability to rewire itself to adjust to new stimuli
Frame of Reference
Our perceptions are affected by their context
