Ch 2 Flashcards
Psychophysics
Relationship between the physical nature of stimuli and Sensations and perceptions they evoke
Photo receptors
Respond to electromagnetic waves in the visible spectrum
Hair cells
Respond to movement of fluid in the inner ear structures
Nociceptors
Respond to painful or noxious stimuli
SomMotosensation
Osmo receptors
Respond to the osmolarity of the blood
Water homeostasis
Perception
Link to experience and internal and external biases
Part of psychology because the same sensation can produce different perceptions in different people
Absolute threshold
Minimum amount of stimulus energy that is needed to activate a sensory system
Threshold in sensation not perception
Will not reach the central nervous system
limina
A threshold under which a stimulus is not precieved
This is the same as sublimal perception which refers to the perception of a stimulus below a given threshold
This is a threshold of conscious perception, meaning that is stimulus will arrive at the central nervous system but does not reach higher order brain regions that control attention and consciousness
Difference threshold
Just noticeable difference
For hearing .68 percent
Webbers law
There is a constant ratio between the change in stimulus magnitude needed to produce a just noticeable difference and the magnitude of the original stimulus
For a higher magnitude stimuli actual difference must be larger to produce a just noticeable difference
Accurate for all my Dality’s except extremely high and low ends of each range
Signal detection theory
Affects of nonsense three factors such as experiences motives and expectations on the perception of stimuli
Houses to look at response bias (is subject is asked to see if it’s stimulus was given or not. Therefore possible outcomes hits miss false alarms and or correct negatives. Is stimulus may not actually be given
Adaptation
Decrease in response to a stimulus overtime
Cornea
Gathers in filters incoming light
Iris
Devise the front of the I in to the anterior and posterior chamber. It has two muscles the dilator (symapthtic) and constrictor pupillary (parasympathetic)
Continuous with choroid and ciliary body
Lens
Refracts incoming light to focus on the retina and is held in place by suspensory ligament is connected to the ciliary muscle (parasympathetic)
Ciliary body
Deuces aqueous humor which drains through the canal Schlemm
Cones
Three forms of short medium and long wave length
Retina
Made of rods and cones. Contains mostly cones in the macula and the center of the macula is the fovea.
The macular corresponds to the central visual fields
Rods and cones
Synapse With bipolar cells which synapse on ganglion cells. Integration of signals from the ganglion cells and edge sharpening is performed by horizontal and amacrine cells
Eye structure
The bulk of the I supported by the vitreous humor on the inside and the sclera and choroid on the outside
Visual pathway
Starts in the eye travels through the optic nerves optic chiasm an optic tracts lateral geniculate nucleus of the Thalamus and the visual radiations to get to the visual cortex
The visual radiations run through the Temporel and parietal lobe’s
Parallel processing
The ability to simultaneously analyze and combine information regarding color shape and motion
Shape is detected by parvocellular cells (high spatial resolution and low temporal resolution)
Motion is detected by magnocellular cells with low spatial resolution and high Temporal resolution
Called feature detection in neuroscience
Catch trials
Trials in which signal is presented
Noise trials
in which the signal is not presented