c2b_default

Nervensystem II: ausgewählte Kapitel

Infos und facts for the second Neuro exam

Infos und facts for the second Neuro exam

88
0.0 (0)

Set of flashcards Details

Flashcards 88
Language English
Category Medical
Level University
Created / Updated 17.06.2018 / 25.10.2018
Weblink
https://card2brain.ch/box/20180617_nervensystem_ii_ausgewaehlte_kapitel
Embed
<iframe src="https://card2brain.ch/box/20180617_nervensystem_ii_ausgewaehlte_kapitel/embed" width="780" height="150" scrolling="no" frameborder="0"></iframe>
Study

What do Dyslexia, Schizophrenia and ASD have in common in respect to MSI?

all have sensory defecits extending beyond a single modality and appear rooted in changes in temporal processes

-> timing of the sensory information transmission within sensory systems could be at the origin of multisensory malfunction

What is SPD?

Sensory processing disorder = a condition where multisensory integration is not adequatly processed in order to provide appropriate responses to the demands of the environment

  • could be due to sympathetic overactivity or less parasympathetic activity
  • timing of ERP (event related potentials differ between SPD and normal developing children

Does the visual cortex play a role in normal tactile perception?

Yes, it is necessary for normal tactile perception. If you inhibit the occipital cortex using TMS, you have reduced tactile performance.

-> the Lateral occipital complex = is responsible for visual and taktile integration -> is a bimodal cortex region (tactile-visual)

 

What if the visual and tactile stimuli don't match? What cortical area is involved?

Then the visual input dominates the tactile input -> the movement of the visual input is perceived, while the tactile overruled. 

In this case, the premotor and occipital cortex(V5 V3/3A) are recruited

Define:

  1. Hypercompensation
  2. cross-modal compensation
  3. perceptual deficiency hypothesis

  1. Hypercompensation: when the absence of one sensory modality leads to changes in the remaining intact senses
  2. Cross-modal compensation: when the sensory-deprived cognitive system has compensated (or substituted) to perform at the same level as healthy individuals
  3. Perceptual deficiency hypothesis: when the lack of one modality results in detrimental effects in the intact modality

How do compensatory changes in the blind and deaf come about?

  1. Intramodal plasticity: when intact sensory systems change to mediate behavioral changes 
    1. Example: increase in represented pitches in the normally afferented auditory cortex of the blind
  2. Reorganisation of multisensory brain structures: recruitment of neurons with multisensory properties to process intact modalities
    1. Example: increase in the recqruitment of posterior Superior temporal sulcus (STS) in deaf individuals monitoring visual displays of moving stimuli
  3. cross-modal (or intermodal) changes: when the brain regions predominantly associated with the impaired system become recruited for tasks involving the intact systems
    1. activation of auditory cortices in deaf individuals

3 general findings on the brain plasticity of death or blind people

  • losing a primarily spatial sense like vision -> triggers perceptual learning through the remaining sensory systems
  • losing a primarily communicative sense like hearing -> triggers perceptual learning of visuospatial abilities
  • deafferented cortical regions are recruited for both blindness and deafness.

Define SSD

Sensory substitution devices = transform the characteristics of one sensory modality into the stimuli of another modality

For istance:

  • present visual information as touch
  • present visual information by audition

Examples:

  • Tongue display unit: vision is replaced through tactile information
  • vision can also be replaced through auditory information

Study