Sensing And Perceiving Flashcards
Sensation
Response of our sense organs to stimulation by the outer worl
Perception
Act of organizing and interpreting sensory experience
How our psychological world represents out physical world
Sensory adaption
Sensory sensitivity diminishes when our senses are constantly stimulating
Ensures that we notices changes in stimulation more than stimulation itself
Acts as a filter to direct our attention to most relevant sensory information
Transduction
Conversion of physical into neural information
Once we know that a physical stimulus is something to attend to, the sense organs convert it into action potentials
Psychophysics
Study of how people psychologically perceive physical stimuli
Absolute threshold
Lowest intensity level of a stimulus we can detect half of the time
-smallest object you can see from a distance or softest sound you can hear etc
Signal detection theory
Takes into account both stimulus intensity and the decision making processes people use in detecting stimulus
Difference thresholds
Smallest amount of change between two stimuli that a person can detect half of the time
Aka just noticeable differences, where the size of the JND is a constant fraction of the intensity of the stimulus - Weber’s law
Bottom up processing
Building a perceptual experience from basic elements of sensation
Top down processing
Perception of the whole guides perception of smaller elemental features
Eg. Our frame of mind, which is ultimately coded in the brain can impact how we perceive things
Perceptual set
The effect of frame of mine on perception
Function of the eye
Bends light, converts light energy to neural energy, and sends that info to the brain for further processing
Most of our visual experience happens not in the eye, but in the brain
Cornea
A clear hard covering that protects the lens
Where light enters the eye
Pupil
Where light entered the interior of the eye
Iris
Coloured part of the eye
Adjusts the pupil to control the amount of light entering the eye
Lens
Light passes through
Bends the light rays to allow the large area of visual space to be represented in the much smeller area of the eye
Retina
Thin layer of nerve tissue that lines the back of the eye
Muscles around the lens alter its shape depending on the distance of an object to allow it to focus light on the retina
Accommodation
Process by which the muscles control the shape of the lens to adjust to viewing objects at different distances
Eye and receptor cells
Light hits the retina and is processed first by the photoreceptors (rods and cones) the deepest layer
Then by the bipolar cells, which send it to the ganglion cells
Horizontal and a machine cells modulate the activity of the other cell types
Transduction occurs in the retina which is made up of neurons
Photoreceptors
Convert light energy into neural impulses and are located in the deepest cell layer
Only retinal cell responsive to light; other cell types are responsive to neurotransmitters
Ganglion cells
Most superficial layer
Ganglion cell axons form the optic nerve that carry information from the eye to the brain