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what are the 4 qualities of sensory input

Modality (type)


what are 1st, 2nd, 3rd order neurons

1st- specialized type of physical energy for each receptor

2nd- More complex analysis (ex basic shape of object)

3rd.- most advanded processing


difference bw 2 types of blind sight

retinal blindness- light can enter eyes but once it makes it to retina there is no processing

Cortical blindness- optic nerves/tracts work fine but prob in visual cortex. Can sense vision to some degree.


what does the topographic organization of the sensory input refer to

Neighboring regions in the periphery are maintained in the CNS (neighboring mechanoreceptors are neighboring in the cns)


how do PSP get activated in receptors (ex mechanotransductor)

mechanoreceptors sensitive to pressure
-when there is a change in pressure it causes sodium channels to open which depolarizes cell


what is activity code

ex. light touch will only cause a couple channels to open where harder touchwill cause an increased number to open (population code)


How quick do pancian corpuscles adapt and methods on how they do

-very quick
-ion channels open/close quickly

- Pancian corpusle damped by tissue (will move corpuscle to side)


what is labled line code

certain types of sensory input is carried on specific lines (tracts)
ex. friendly touch vs noxious touch


what is pattern code(and ex)

- taste
-spectrum of flavour of something


what are nociceptors and how do they get into heighted states

Responds directly to tissue damage or stim that has potential to damage tissues

when cells are dammaged chem mediators release chems that sensitize nociceptors


What temps do thermoreceptors detect and how does the info travel

cold- bw -20 is
hot- up to 45

travel on specific labeled line tracts


what receptors for touch found on smooth skin



what doe joint capsul mechanoreceptors detect

muscle pulls
deep ressure


What do muscle spindles detect and when do they cause mm to fire

Sensitive to strethc
-when there is no stretch detected will cause gamma fibes to cause contraction


what do cone and rod cells detect

cones- color
rods- b+ww


when there is light what happens in the light cells (and what does it cause to the channels in the end; general)

1. light breaks down rhodopsin to retinal + opsin
2. retinal activates G pro
3. G pro activates c GMP phosphodieterase which decreases cGMP which causes sod channels to close


what happens when light is there in 1st and 2nd order neurons

retinal- rhodopsin brocken down. Causes decreased cGMP, so na channels closed and no glutamate release.

Bipolar- no NT allow cGMP to build up on bipolar which opens sod channels on ON receptor which releases glutamate to ganglion cell


What happens when there is no light in 1st and 2nd order neurons

retinal- no rhodopsin released so cAMP increases allowsing sod channels to open and glutamate release

ON- cGMP decreased closes sod channels

OFF- cGMP thrives allowing sod channels to open and releases NT to ganglion.


What do horizontal cells do

Ensure there is no incorrect activaion (off cells are off in presence of light)
-enhances contrast


what is a low tolerance to hot foods associated w

increased nociceptors on the tongue


salts and acis activate this type of channel whereas Carbs lead to this type of channel

Salts + acids activate ionotropic channels

Carbs- activate g protiens


What 2 tastes have cross over in high conc

High conc of sour substances may cross over and acttivate salt receptor


what is the CNS refelx for hearing

Tightens mm attached to ossicles to dampen sound


What happens when there is an unexpected loud sound in the inner ear

Causes spastic type of mm contraction that causes ringing in ear due to vibration of ossicle


where are high and low frquencies heard in the chochlea

basilar end for high frequencies (shorter hair follicles)
Apical end for low frequeincies


what is the longest hair cell called and which way of bending causes depolarization and hyperpolarization

largest is kinocillim

Bending towards= depolarization
Bending away= hyperpolarization


What happens with ppl w R sided Strabismus

R eye might have down and out

May start to tilt head to R to compoensate


How do we localize sound (2)

interneural intensity dif- difference in intensity bw ears

Itraoral time dif- time dif bw two ears


Where is interneural and intraoral time diff processed

Interneural intensity- Lat sup olivary nucleus

Intraoral- Medial sup olivary dif


max delay of tiem dif ears can detect and what frequencies are better localized