Topic 3 Perception pt 1 Flashcards
True or False: What we sense (in our sensory organs) is the same as what we perceive (in our minds)
false: they are NOT the same
We are asked to find the cat in an image. After a few minutes, we spot that cat. What happened?
the light entering our eyes remained the same, but our perception of the image changed
What is the problem with perception?
We are trying to understand what is out there in the world
What is the challenge with perception?
The inverse problem: how we determine the distal stimulus from the proximal stimulus
distal stimulus
what is out there in the world
proximal stimulus
what we sense (the image on the retina)
What sources of information contribute to our perception? (5 points)
- ) Genes
- ) Past experience
- ) Internal state
- ) Environmental context
- ) Proximal stimulus
Information learned on a timescale of current episode
internal state
information learned on a timescale of human life
past experiences
information learned on a timescale of evolution
genes
Touch, Thermal, and Pain are all part of
somatosensory system
define and give examples of a proximal stimulus
proximal stimulus is what stimulates the sensory receptors
examples of proximal stimulus includes light, sound waves, touch
sensory receptors
specialized cells that convert external phenomena into neural signals
neural pathway of senses
from sensory receptors via thalamus to cerebral cortex
percept
mental representation of a distal stimulus
wherever it is we are looking, the light from that location arrives in the ______
fovea
What is the blind spot
a hole in the retina where all the axons depart. In the blind spot, there are no photoreceptors, caused by optic chiasm
where are the photoreceptors?
back of the retina
What are the types of photoreceptors?
rods (1 type) and cones (3 types)
What are the 3 types of cones
S (smallest wavelength)
M (middle wavelength)
L (longest wavelength)
What happens to the density of cones as it gets closer to the fovea?
increases
what happens to the density of cones at it gets further away from the fovea?
decreases
what happens to the density of the rods at it gets further away from the fovea
increases
what happens to the density of the rods at it gets closer to the fovea
decreases
how is sound created
Sound is created by changes in air pressure.
organ of corti
responsible for transduction and is located in the inner ear
what is the basilar membrane
stiff structural element within the cochlea of the inner ear
in the basilar membrane, the location of maximal excitation depends on the _______.
Location of maximal excitation depends on the frequency.
Low frequency causes vibration near the end
High frequency causes vibration near the base
Summarize the primary auditory pathway (7 points)
- ) Auditory Nerve
- ) Cochlear nuclei (medulla)
- ) Superior olivary nucleus (pons)
- ) Nucleus of lateral lemniscus (pons)
- ) Inferior colliculus (midbrain)
- ) Medial geniculate nucleus (thalamus)
- ) Primary auditory cortex
Which mechanoreceptors are most superficial?
Meisser and Merkel
Which mechanoreceptors are deepest?
Pacinian and Ruffini
Which mechanoreceptors are fast adapting?
Pacinian and Meissner
Which mechanoreceptors are slow adapting?
Ruffini and Merkel
Summarize the somatosensory pathway (4 points)
- ) Dorsal root ganglion
- ) Cuneate / Gracile nuclei (medulla)
- ) Ventral posterior nuclei (thalamus)
- ) Primary somatosensory cortex
2 layers of cells that light has to pass through to get to the rods and cones of the retina
- ) ganglion cells
2. ) bipolar cells
What does the medial geniculate nucleus do?
detects sound waves and is responsible for thalamic relay between the inferior colliculus and the auditory cortex
