Sensory processing and Perception Flashcards
Sensory receptors communicate 4 properties to the CNS
Location, modality (type of stimulus), intensity, and duration
Exteroreceptors vs Interoreceptors
Exteroreceptors- respond to stimuli from outside world
Interoreceptors- respond to stimuli inside the body
Various stimuli from inside body
Sense pain from within the body and dehydration/ overhydration
Olfactory and gustatory receptors both respond to which stimuli
Chemical stimuli
What cells are responsible for hearing? These are found in inner ear, convert pressure signals from sound waves into action potentials. they also respond to pressure to sense rotational acceleration
Hair cells
Semicircular canals contain a fluid called? This fluid moves in response to rotational acceleration
Endolymph
Hair cells in which structure send rotational information to the nervous system
Crista ampullaris
Type of mechanoreceptors that detect light touch
Tactile corpuscles
Type of mechanoreceptors that respond to sustained pressure
Merkel nerve endings
Type of mechanoreceptors that sense deep pressure beneath the surface of the skin
Ruffini endings
Type of mechanoreceptors that respond to high-frequency vibrations
Pacinian corpuscle
Receptors that detect pain
Nociceptors- some respond to mechanical stimuli, some to thermal stimuli, and some to chemical stimuli (ex. Capsaicin - spicy food)
These Interoreceptors detect pressure inside the body, like walls of blood vessels. These are subset of mechanoreceptors
Baroreceptors
Blood pressure is linked to 2 properties
Blood volume and hydration
These detect concentration of solutes in blood
Osmoreceptors
These receptors are found in and around muscles, tendons, joints. Give us a sense of relative position of the parts of our body in space. (Kinesthetic sense)
Proprioceptors
Proximal vs Distal stimulus
Proximal: what the sensory receptor picks up on
Distal: the environmental source of the signals
The threshold that a stimulus must cross in order to consciously perceive it
Threshold of Conscious Perception
The level of intensity that a stimulus must have in order to be picked up by sensory neurons. If a stimulus does not hit the threshold, it is not registered by our bodies
Absolute threshold
T or F. The level of stimulus can be pass the threshold of conscious perception but never pass the absolute threshold
False. The opposite is true. The absolute threshold can be passed but not the threshold of conscious perception
The smallest change in magnitude of a stimulus that we can perceive as being different. Also known as the difference threshold
Just- Noticeable Difference (JND)
Tests whether research subjects can tell the difference between 2 stimuli
Psychophysical discrimination testing
For any given sensory input the JND will be a constant proportion of the original input
Weber’s Law (breaks down at extremes- too strong/ too faint)
Bear actually present and bear is perceive
Hit
Bear is actually present but bear not perceived
Miss
Bear actually absent but bear perceived
False Alarm
Bear actually absent and bear not perceived
Correct rejection
T or F. Signal detection can vary across people but is not affected by psychological states.
False. First part is correct but psychological states can affect signal detection
Sensory adaptation occurs where?
In the brain
These receptors are slow to adapt to stimuli
Tonic receptors
These receptors send a burst of action potentials, then stop. (Fast adaptation)
Phasic receptors
Ex. Hair follicles
Bottom up processing vs top-down processing
Bottom-up: individual pieces assembled to see the bigger pic
Top-down: brain decides what it is looking for, then assembled individual pieces to support that pic
We perceive objects or shapes that a re close to each other as forming groups
Principle of proximity
Objects that are similar in some way will be perceived as belonging to a group
Principle of similarity
If multiple objects intersect or overlap, we tend to perceive them as relatively few uninterrupted objects
Principle of Good Continuation
We infer the presence of complete shapes even when they’re incomplete
Principle of closure
Symmetrical objects are more likely to be perceived as whole than asymmetrical objects
Principle of symmetry
Law of Pragnanz
Objects are interpreted in the simplest and most meaningful ways
(For Gestalt Principles)
Eye structure that turns certain wavelengths of light into action potentials
Retina
Cones and rods are photoreceptors located at which structure of the eye?
Retina
Which photoreceptor is responsible for perceiving color and fine detail
Cones
Short wavelength type of cones is responsible for sensing which color? What is the wavelength
Blue- 420 nm
Medium wavelengths type of cone is responsible for sensing which color? What is the wavelength?
Green- 530 nm
Long wavelength type of cone is responsible for sensing which color? What is the wavelength?
Red- 560 nm
Where are cones most commonly located?
Fovea centralis and macula (central region around the fovea)
Which photoreceptor is responsible for sensing visual input in low-light conditions (responsible for night vision)?
Rods
What is the pigment that the rods contain. This doubles as a photoreceptor protein and is extremely sensitive to light
Rhodopsin
T or F. There are more cones than rods.
False. There are about 120 million rods and only 6 million cones.
Which 2 structures of the eye focus the light?
Cornea and lens
What structure of the eye actually lets light into the eye and which one blocks the light that is not supposed to get into the eye?
Pupil and cornea respectively
Which structure of the eye contains the dilator pupillae and constrictor pupillae?
Iris
Which muscle adjusts the lens?
Ciliary muscle through the suspensory ligaments of lens
Which structure of the eye surround the retina, supply blood, and absorb excess blood?
Choroid
What is the outermost layer of the eye?
Sclera- gives the eye white color
The cones and rods are not directly in contact with optic nerve. Instead they synapse onto?
Bipolar cells
T or F. Bipolar cells have their cell body in the middle, with the dendrites in one end and axon on the other
True
T or F. Each bipolar cell is connected to only one cone or rod
False. Each is connected to many. Information is integrated
Bipolar cells synapse with ________, which are the components of optic nerve
Ganglion cells
Cells between cones/rods and bipolar cells. they inhibit photoreceptors, helping the eye to adjust to high versus low-light conditions and also synapse into bipolar cells too
Horizontal cells
Cells in between bipolar cells and ganglion cells.
Amacrine cells
Which 3 structures are mediary between rods and cones of the retina and the ganglion cells of the optic nerve
Horizontal, bipolar, and amacrine cells
The bundle of nerves carrying visual information
Optic tract
The optic tract runs through ________ _________ ________, which is contained in the thalamus
Lateral geniculate nucleus (LGN)
The main relay station for inputs from the retinas
Thalamus
Specialized types of neurons in LGN
Magnocellular neuron and Parvocellular neurons - opposite functions
Ability to pick up details
Temporal resolution
Ability to see in detail
Spatial resolution
Magnocellular neurons function
Specialize in detecting motion. Not good at picking up details
Parvocellular neurons function
Specialize at picking up details. Not good at detecting motion
Objects that are close to us move further across our visual field than objects that are far from us
Motion Parallax- cue to perceive depth
Detection of individual stimuli
Feature detection
Integrate multiple inputs simultaneously
Parallel Processing
Systematically giving attention to one thing at a time
Serial Memory Processing
Sound waves are ____________ waves that, in air, manifest as regularly repeating changes in __________ as air molecule move back and forth
Longitudinal ; pressure
What cells are responsible for hearing?
Hair cells
Where are the hair cells located?
In the inner ear within a structure called the organ of Corti
T or F. The sound waves causes hair cells to sway, opening up sterocilia that allows the passing of positively charged ions which in turn cause the influx of Ca2+ Ions through voltage-gated Ca2+ channels
True
3 sections of organ of corti
Basilar membrane in the bottom,
Endolymph containing hair cells in the middle,
Tectorial membrane- rigid structure
3 bones in the middle ear (ossicles0
Malleus, incus, and stapes
Which membrane divides outer ear from middle ear?
Tympanic membrane
Connection to nasal cavity which is basically a valve that equalizes the pressure between the middle ear and the environment
Eustachian tube
These can amplify the the vibrations from the eardrum by as much as 10 times
Ossicles
T or F. The thickness of the basilar membrane isn’t constant and different thicknesses respond to different frequencies of vibrations
True
The thickest part of the basilar membrane is closest to the oval window and responds to (low/ high) frequency vibrations
High
Allows the brain to infer pitch of sound based on which hair cells send signals
Place theory
What structure divided middle ear and inner ear?
Oval window
The nerve signals generated by the hair cells in the organ of Corti are transmitted through the?
Vestibulocochlear (auditory) nerve
The auditory signals pass through (medial/ lateral) geniculate nucleus in the thalamus on their way to the auditory cortex in the temporal lobe
Medial
Hearing:
Left hemisphere vs Right hemisphere
Left: speech
Right: background noise
Which cells are responsible for our vestibular sense?
Hair cells
3 Endolymph-containing structure called ______________ __________ are responsible for sensing rotational acceleration
Semicircular canals
Each end of the semicircular canal ends in a bulge called an _______, which contains hair cells
Ampulla
This sense linear acceleration
vestibule
Utricle vs Saccule of the vestibule
Utricle: detects motion in the horizontal place
Saccule: detects motion in the vertical plane
Function of cochlea, semicircular canals, and vestibule
Cochlea: sound
Semicircular canals: rotational acceleration
Vestibule: linear acceleration
CaC)3- containing structures in the utricle and saccule that helps stimulate hair cells
Otoliths
Minimum distance for distinguishing two point stimuli
2 point threshold
The smaller the 2 point threshold is the (less/ more) sensitive the area is
More
Our skin is cooler than our normal body temp.
Skin: 80- 90s
Core body temp: 98.6
Pain turned on/ off based on input
Gate Theory of Pain
Taste pathway
Taste center of thalamus -> gustatory cortex (in insula)
Smell pathway
Olfactory bulb -> olfactory tract -> limbic system
