Neuroanatomy- Auditory/ Vestibular and Visual Pathways Flashcards
Which bone of the skull contains the auditory/vestibular system?
Temporal
Which cranial nerve is associated with hearing?
CNVIII
Which foramina does CNVIII pass through?
Internal acoustic meatus
What is the role of the spiral ganglion?
Bipolar neurons stimulated by hair cells carrying action potentials from organ of Corti to cochlear nuclei in pons
Where is the primary auditory cortex found?
Inferior to the lateral fissure and the central sulcus on left side of brain
Where do fibres carrying information about low/high frequency sound information end up in the auditory cortex?
Low frequency= anterolateral part
High frequency= posteromedial part
What is aphasia?
Inability to use language
What are clinical signs of damage to Broca’s area?
Difficulty producing language, use few words and only say most important words in sentence
No difficulty comprehending language
Motor or expressive aphasia
What are the clinical signs of damage to Wernicke’s area?
Difficulty comprehending language.
Defects from words out of order to meaningless words
Sensory or receptive aphasia
What information is used to maintain equilibrium?
Vision
Proprioception
Vestibular Apparatus (Labyrinth)
Which cranial nerve is associated with balance?
CNVIII Vestibular nerve
Where does vestibular information project on the cerebral cortex?
Bilateral, less well defined
No agreed region of brain that is exclusively for vestibular stimulation
Optic tract wraps around which part of the brainstem?
Midbrain
Where are visual areas on the cortex?
Primary visual cortex and visual association cortex are in occipital area of brain behind parietal-occipital sulcus
The lateral geniculate nucleus is associated with visual/auditory cortex?
Lateral= visual
The medial geniculate nucleus is associated with visual/auditory cortex?
Medial= auditory
In relation to the calcimine sulcus where does the lower visual field vs upper visual field project to the gyrus?
Lower= gyrus superior to calcarine sulcus Upper= gyrus inferior to calcarine sulcus
In comparison to the rest of the visual field, does the macula occupy a greater/smaller proportion of the visual cortex?
Greater for higher acuity
What are the two brain areas that are involved in eye movement?
Visual cortex
Frontal eye field
Which type of eye movements is the visual cortex responsible for?
Movements in response to visual stimuli e.g. tracking moving objects
Which type of eye movements are the frontal eye fields responsible for?
“Movements of command”
Movements independent of moving visual stimuli
What is the difference between movements of command and tracking movements?
Tracking movements are smooth
Movements of command are “jumpy”
Example: move eyes from left to right then do it following a finger
If vision is lost in the same visual field in both eyes, what is the term for this and the opposite of this?
Homonymous
Opposite of this would be heteronymous
What are association fibres in the white matter?
Fibres that connect cortical sites lying in the same hemisphere
What are commissural fibres in the white matter?
Fibres that connect one hemisphere to the other, usually connecting areas with similar function
What are projection fibres in the white matter?
Fibres that connect hemispheres to deeper structures including thalamus, corpus striatum, brain stem and spinal cord
