cortical anatomy and clinical correlates

Question 1

A lesion where in the brain could cause isolated bilateral leg weakness?

Answer 1

an expansive lesion in the falx cerebri touching the motor cortex for the legs on both sides

Question 2

What is the role of the supplemental motor cortex? What do you see with a seizure in this area?

Answer 2

Learned motor sequences. Seizures here cause bilateral motor manifestation due to bilateral connections. (without loss of consciousness)

Question 3

How does activation of frontal eye fields affect eye movement?

Answer 3

Activation results in conjugate eye movements in the opposite direction to the side activated. ie left sided activation results in the eyes looking to the right.

Question 4

What happens to eye movements in a seizure of the frontal eye fields compared to a stroke?

Answer 4

In a seizure there is increases activity in the frontal eye field resulting in the usual action - conjugate gaze away from the activated side. In a stroke there is decreased activity so the unopposed baseline activity of the opposite side causes conjugate gaze towards the affected side.

Question 5

What is the main function of the dorsolateral pre frontal cortex?

Answer 5

Executive planning (mnemonic SOAP) sequencing, organisation, abstraction and planning

Question 6

What is the orbitofrontal cortex responsible for?

Answer 6

emotions, empathy

Question 7

What is the mesiofrontal cortex responsible for?

Answer 7

Get up and go or motivation. loss of get up and go = Abulia. Can remember it because its oriented vertically (get up and go)