NEUROANATOMY Flashcards
Precentral gyrus (part of the frontal lobe) is
primary motor cortex. The representation of different body parts in this region is often termed as a homunculus
Postcentral gyrus (part of the parietal lobe)
primary somatosensory cortex
The lateral sulcus (Sylvian fissure) divides
insula
frontal lobe from the temporal lobe.
The insula, regarded as the fifth lobe of the cerebrum = located deep in the Sylvian fissure.
Insula is = the seat of the primary gustatory cortex.
middle frontal gyrus constituting
the dorsolateral prefrontal cortex,
often considered to be responsible for executive functions of the
human brain.
Most fundamental brain functions are represented bilaterally.
Higher levels of associative functions usually lateralize to one or other hemisphere
* ? is the dominant hemisphere
The hemisphere contralateral to the dominant hand is the dominant hemisphere, and it mediates
language and speech functions
The planum temporale (superior temportal gyrus)
triangular region on the upper surface of the
superior temporal gyrus. It is important for language processing and is larger on the left than the right hemisphere in 65% brains
Limbic system/ Papez circuit
involved in
- mediation of emotional responses (through amygdala)
- influencing neuroendocrine responses (via hypothalamus)
- reward system regulation (via nucleus accumbens).
= considered to be evolutionarily older than the higher cortical centres.
Medial temporal structures
hippocampus, amygdala, entorhinal and parahippocampal cortex.
Hippocampus = memory processes. few brain regions where the continuous production of new neurons
Amygdala = fear conditioning and emotional regulation
Basal Ganglia
(Group of gray matter nuclei forming the largest subcortical structure in the brain)
- The planning and programming of movement
- Include striatum (caudate nucleus + putamen)
- pallidum (globus pallidus)
- Subthalamic nucleus
- Substantia nigra
- receive crucial inputs from glutamatergic corticostriatal projection
Frontal eye fields are located
Are responsible for..
- precentral sulcus at caudal end superior frontal gyrus
- responsible for voluntary saccadic movements of eye
Primary auditory area located in?
Heschls gyri
Prosopagnosia
Inability to recognise faces
Deficit in parietal lobe functioning :
- Gerstmanns syndrome
- Balint syndtome
**- Gerstmanns syndrome: Lesion in Left inferior parietal lobe around angular gyrus
- agraphia, acalculia, finger agnosia, L-R disorientation
(sweaty german man, cant tell L from R, cant see fingers so salute hands, cant write cant do math)
- Balint syndtome :
bilateral damage to posterior parietal lobe
- optic ataxia, ocular apraxia, simultagnosia
Frontal lobe function
motor (motor cortex)
executive cortex (premortor cortext)
decision making (prefrontal)
working memory (prefrontal)
Language (broca)
inhibition and personalitry - orbitofrontal
saccadic eye movements- frontal eye fields.
Parietal lobe function
Touch + Proprioception - somatosensory area
Visuospational processing- R parietal lobe
Praxix (dressing)
Somatognosia (awareness own body)
Reading, writing, naming- L parietal lobe
Temporal lobe function
Memory + Deductive reasoning - L temporal
Language comprehension - L temp
Auditory perception - L temp
affective prosody - R temp (loss converying emotions)
Face recognition (prosopagnosia)
Kluver Bucy syndrome
Bilateral lesions of anterior temporal lobe
- hyperorality
- placidity
- prosopagnosia (cant recognise faces)
- hypersexuality
- memory loss
associated with herpes enceph, trauma, picks
Occipital lobe
Perception visual sensation
lesions here = homonymous hemianopia
Anton babinski syndrome
Cortical blindness
- denial of blindness despite evidence and confabulation of missing sensory input
Hippocampus
Mainly involved in creation and recollection of declarative memory
what area crucial for Reward circuit
Nucleus accumbens and ventral tegmental area
Anterior commisure
Implicated in sexual orientation
connects two amygdala, pain and olfactory tracts
Huntington
- CAG repeat
- neuronal loss in basal ganglia
Basal ganglia involved in
Gating of initiation of voluntary movements
overactive caudate nucleus
underactive caudate nucleus
- OCD overactive
- ADHD underactive
Substantia nigra = nucleus in midbrain
dark black due to melanin (byproduct dopamine)
- pars compacta = dopaminergic
- pars reticula - GABA nergic
Superior colliculus
Inferior colliculus
= together - corpora quadrigemina
Superior colliculus - Eyes
Inferior colliculus - Ears
Sleep is regulated through mononergic neurons in
Reticular formation in brain stem
Cerebellum divisions
anterior lobe- recieved proprioception from muscles and joints
posterior lobe- motor info from cortex
vermis- truncular musculature stability
flocconodular lobe- balance
The components of the basal ganglia are as follows:
Striatum (caudate, putamen, nucleus accumbens)
Subthalamic nucleus
Globus pallidus
Substantia nigra (divided into pars compacta and pars reticulate)
caudate nucelus and striatum atrophy is seen in?
Huntingtons
Cause of parkinsons?
loss of dopaminergic neurons in substantia nigra pars compacta
what structure has been associated with alzheimers disease?
nucleus basalis of meynert
Normal Pressure Hydrocephalus (NPH) is a condition characterised by ?
the triad of gait disturbance, dementia and urinary incontinence
expected to occur following damage to the dominant cerebral hemisphere?
Right-left disorientation
Alexia without agraphia infarct?
where is infarct? = Infarct to left PCA
locus coerealeus
part of ARAS
deals with emotions + sleep wake
which area of brain most active when dreaming?
also where is sleep activated?
pons
THE PONS
