8.2 Flashcards
4 aspects of somthing that can be percieved?
- Modality
- intensity
- Duration
- Location
describe what is Modality?
what kind of Receptor? Quality?
vision, hearing, taste, smell, touch, cold, warm, prpriocepption, acceleration, pain….
give an example for a labeled line?
visual pathway from the retina to the visual cortex
define the threshold?
point when the stimulus in 50% of the cases is detected and in 50% of the cases no stimulus occurs
what does the threshold depend on?
intensity of the stimulus
how can we code intensity?
- AP frequency (high f of AP -> larger intensity)
- Population coding
- Related but different type of R are activated
how can we alter the duration of a percieved sense?
by adaptation
how does the location of the stimulus can be analize?
somatotopic organization
sensory neurons are typically ______
Pseudounipolar
*Bipolar in the retina, olfactory, auditory, vestibular
cell body of the Pseudounipolar neuron located in
Dorsal root Ggl
what somatosensory R types do we have?
mechanareceptors
thermoreceptors
nociceptors
what are the two possibilities for adaptation of receptors?
- rapidly adapting
2. slowly adapting
rapidly adapting receptors mechanism
surrounded by a capsule
can only detect signal if its quickly on and off
write down somatosensory R
- Pacinian (rapidly adapting- vibration)
- Ruffini (slowly adapting- stretch)
- Meissner (rapidly adapting- touch)
- Merkel (slowly- pressure)
- Muscle spindle and Golgi Tendon Organ (stretch)
- Thermoreceptors- (slowly adapting- free nerve endings)
cold VS hot fibers?
cold- A delta fibers
hot- C fibers
2 somatosensory pathways?
- Dorsal Column-Medial Leminiscus
2. Antero-Lateral (Spino-Thalamic Tract)
Dorsal Column-Medial Leminiscus receptors?
Pacinian Ruffini Merkel Meissner and proprioceptors
Dorsal Column-Medial Leminiscus responsible for?
fine touch
vibration
proprioception
2-point discrimination
Antero-Lateral (Spino-Thalamic Tract) receptors?
warm and cold thermoreceptors
nociceptors
Anterior SpinoThalamic Tract responsible for?
crude touch
Lateral SpinoThalamic Tract responsible for?
pain and temparture
write down somatosensory pathways
online picture
Broadman’s area for somatosensory pathways?
in the post-cental gyrus
BA= 3,1,2
