Perception Flashcards
What is Perception
is how we interpret and make sense of sensory information.
The Inverse Problem
Our brain takes the sensory information we receive (proximal stimulus) and turns it into a meaningful picture of the world (perception) based on the actual object (distal stimulus).
Genes, Past Experience, Inter State, Environmental context, Proximal Stimulus.
( TIMESCALE)
Genes: Information
learned on
timescale of
evolution
Past experience:
Information learned
on timescale of a
human life
Internal state:
Information learned
on timescale of
current episode
Environmental
context:
Information learned
now
Proximal stimulus:
The stimulus itself
Sensory Systems
Vison, Somatosensorial, Audition
Distal stimulus:
An object or process out in the world
Proximal stimulus:
The energy or matter that touches or affects the senses.
Sensory receptors
Specialized cells to transduce
(convert) external phenomena (light, sound, pressure,
etc…) into neural signals
Neural pathway(receptors)
Sensory receptors send signals to the thalamus, which relays them to the cerebral cortex for processing.
Hierarchy of cortical areas
( construct) :
Attempt to construct
useful representation of distal stimulus
Percept( Mental)
Mental representation of the distal
stimulus
Visual System is your
EYE
Transduction is
conversion of light into neural signals to retina
Photoreceptors
Specialized cells for transduction
Two types of Photoreceptors
Rods and Cones
Blindspot
Nerve fibers exiting the eye to the cortex.
Photoreceptors: 1 Type of rods, 3 types of cones.
short Blue cone, Medium green cone, long red cone.
Retinal receptor
density(Fovea)?
Cones, concentrated in the fovea, offer sharp vision and detail.
Primary Visual Fields
The left visual field from both eyes is processed in the right V1.
The right visual field from both eyes is processed in the left V1.
Some nerve fibers cross at the optic chiasm, sending visual information from each side of the visual field to the opposite side of the brain.
what are the pathways( there are 3)
Pathway
Ganglion cells: These cells gather visual information from other cells in the retina and send it to the brain.
LGN (thalamus): A part of the brain that connects the optic nerve to the thalamus and helps process vision.
Primary visual cortex: The part of the brain that processes what we see.
Does sound work?
Sound = changes in air
pressure
Vibrations Travel through..
bones of middle ear
(ossicles) to oval window
of cochlea
What is the Cochlea?
fluid filled
tubes with basilar
membrane
Inner Ear( travels)
pressure waves travel down the
cochlear and back out
towards the round window
In the Inner ear there are?
Hair cells, along basilar
membrane in cochlea
detect vibrations and
Pressure waves cause
hair cells (cilia) to sway
Hair Cells
Look up photo for Hair cells
All the different parts( 1 2 3) to the Primary auditory pathway
Auditory Nerve & Cochlear Nuclei
(Medulla): Sound signals start processing here.
Cochlear Nuclei, Superior Olivary Nucleus, & Nucleus of the Lateral Lemniscus: Help process sound and locate it.
Inferior Colliculus, Medial Geniculate Nucleus & Primary Auditory Cortex: Further process sound and interpret it.
Damage along the auditory
pathway different parts
Conduction Deafness: Damage to the outer/middle ear blocks sound.
Sensorineural Deafness: Damage to inner ear or auditory nerve.
Primary Auditory Cortex Damage: Hard to locate sounds.
Higher-Order Auditory Cortex Damage: Trouble understanding speech, music, and emotion in tone.
Types Somatosensory system (MTNP)
Mechanoreception: Senses pressure, vibration, and touch.
Thermoception: Senses hot and cold.
Nociception: Senses pain from chemicals, pressure, or heat.
Proprioception: Senses body position and movement.
Mechano -receptors
for touch
are sensory organs or cells that respond to mechanical stimulation such as touch, pressure, vibration, and sound from both the internal and external environment.
Receptors ( MMPR)
- Mesissner Corpuscle (RA1)
- Merkel Cells (SA1)
- Pacinian Corpuscle (RA2)
- Ruffini endings (SA2)
Receptive Field on the finger and what color is the finger?
RA1: very red
SA1: lil red
RA2: light soft red
SA2: light light red
Primary Somatosensory pathway parts ( 1 and 2)(3 and 4)
Dorsal Root Ganglion: Sends sensory signals from the body to the brain.
Gracile & Cuneate Nuclei (Medulla): Help transmit body sensations to the brain.
Ventral Posterior Nuclei (Thalamus): Relays touch and body sensations to the cortex.
Primary Somatosensory Cortex: Processes touch, pain, temperature, and body position.
