Functional anatomyBrain structure and function Flashcards
You are working as a PA in an emergency department. An 18 year old student comes to see you complaining of headache and feeling feverish. On examination he has photophobia, a non-blanching rash on his abdomen and a stiff neck. What is the most likely diagnosis?
Meningitis
What is this ?
Extradural Hematoma
What is this?
Subdural
What can happen within the subarachnoid space?
Subarachnoid Haemmeohage
This happens because there are blood vessels there !!
What is the presentation of a subarachnoid haemmoraghe?
Thunderclap headache
What are gyri and the sulcus of the brain?
What does the middle cerebral artery supply ?
The MCA supplies parts of the frontal lobe, parietal lobe and temporal lobe
What does the anterior cerebral artery supply ?
You will note that the ACA supplies parts of the frontal and parietal lobes
What does the posterior cerebral artery supply?
The PCA supplies the occipital lobe and part of the temporal lobe
What areas are perfused by the vertebrobasilar arteries ?
Areas perfused:
Medulla, pons, midbrain (brain stem)
Cerebellum
Thalamus
Occipital cortex
In 1848, Phineas Gage survived an iron bar passing through his brain in a railroad accident. After his recovery his personality was drastically different. Which part of the brain do you think was affected?
Frontal lobe
Frontal lobe- functions
1- Personality
2- Motor Function
3- Memory and language
4- Judgement
What is the blood supply for the frontal lobe ?
Blood supply is from the:
Anterior cerebral artery (ACA) and Middle cerebral artery (MCA)
A 78 year old man sustains a head injury in a road traffic accident. He is able to understand what is said to him but finds it very difficult to speak fluently in response. Which part of the brain is affected?
Brocas Area
What is brocas area important for ?
- The PRODUCTION of speech, the actual motor function. It is not used for comprehension.
- Processing thoughts into words
- Damage = able to understand but difficult to form words
What is the blood supply to Brocas area ?
Middle cerebral artery
Where is the Brocas area located ?
This new insight about Broca’s area, which is located in the frontal cortex.
An 87 year old lady presents to ED with a 1 hour history of left sided facial droop and arm weakness. Which part of the brain is affected?
Right Precentral Gyrus
Where is the motor cortex located ?
What is the blood supply ?
Precentral gyri
Supplied by Middle Cerebral Artery (MCA) and Anterior Cerebral Artery (ACA)
What does the motor cortex do ?
Controls movement of contralateral head, neck, trunk, arm and leg
Symptoms will be contralateral to the lesion
If a patient presented with leg weakness what part of the motor cortex would you expect there to be an issue with ?
ACA
If a patient presented with facial what part of the motor cortex would you expect there to be an issue with ?
MCA
A 19 year old patient comes to ED following a seizure. She describes hearing sounds that weren’t there, a strong feeling of fear, feeling like her heart was racing and profuse sweating. Her mother states that following this she had a wide eyed stare and was smacking her lips. She would not respond to her name.Which part of the brain was affected?
Temporal lobe
What is the role of the temporal lobe?
1) Organisation of sensory input
Auditory perception
Visual perception
Facial recognition
Smell
2) Memory
3) Speech and language
Especially language comprehension
4) Emotional Responses
What is the blood supply to the temporal lobe?
-Middle cerebral Artery
- Posterior cerebral Artery
What is the role of the limbic system ?
Self and species preservation behaviours
Autonomic and endocrine responses to emotional stimuli
Parts located within the temporal lobes:
Olfactory cortex
Hippocampus- memory formation and association
Amygdala- autonomic responses associated with fear