Introduction to Gross Brain Laboratory and Spinal Cord Exercise Flashcards
The somatosensory cortex is _________ to the Rolandic fissure. It is also called the ____________.
posterior; postcentral gyrus
The somatotopic area of the wrist is _________ to the area of the hand.
medial
The area where the motor-neuron axons cross is called the ____________.
decussation
The cingulate gyrus is immediately superior to the _____________.
corpus callosum
Superior to the cingulate gyrus is the ____________.
cingulate sulcus
The motor neuron axons are wrapped in a structure called the ___________.
internal capsule
The corticospinal pathway is also called the ___________.
pyramidal tract
The caudate and putamen together are called the ___________.
striatum
The corticospinal tract splits the ___________ into the medial caudate and lateral putamen.
ganglionic eminence
The internal capsule has a bend in ___________ slices.
axial
The corticospinal tracts are on the _________ surface of the medulla.
ventral (these form the “eyes” in Dr. Ojemann’s mnemonic)
Motor neurons from the corticospinal tract synapse on ___________.
alpha motor neurons – which reside in the spinal cord and send axons into the periphery
The intermediolateral cell column (aka lateral grey column) in the spinal cord contains ____________.
sympathetic neurons
Hyperreflexia is caused by __________ damage.
upper motor neuron
What is spasticity?
Inability of muscle cells to relax
What are fasciculations?
Individual motor units contracting, leading to noticeable rippling of muscle fibers
Paresis is ____________.
weakness (as opposed to plegia, which means total loss of control)
The ___________ contains all of the sensory axons from the lower extremity.
fasciculus gracilis
The ____________ contains all of the sensory axons from the upper extremity.
fasciculus cuneatus
The fasciculus cuneatus is _________ to the fasciculus gracilis.
lateral
Pain-sensing neurons synapse on a fasciculus in the spinal cord called the __________.
Lissauer’s fasciculus
What is the division of the two hemispheres called?
The interhemispheric fissure
The insula is within the __________.
Sylvian fissure
What is between the paracentral lobule and the precuneus?
The cingulate sulcus
What is the corticospinal tract when it passes the medulla?
The medullary pyramid
Where does the corticospinal tract become contralateral?
In the medullary decussation
Describe the differing responses to upper-motor neuron (UMN) and lower-motor neuron (LMN) injury.
UMN: immediate weakness followed by hyperreflexia and spasticity
LMN: immediate and long-lasting weakness
Describe the cell chain involved in sensing pain.
First neuron enters spine –synapses on neuron that crosses midline then extends to the thalamus – synapses on thalamic neuron that carries signal to cortex
In the cerebrum, the fibers of the internal capsule splay out into ______________.
the corona radiata
The putamen is ____________ to the globus pallidus.
lateral
In the midbrain, the internal capsule is referred to as ___________.
the crus cerebri
The caudate is ____________ to the thalamus.
superior
Approximately _________ percent of the corticospinal axons decussate.
80%
How many lower-motor neurons can one upper-motor neuron innervate?
A “pool” (Ojemann’s word)
Muscle fasciculations are characteristic of _____________ damage.
lower-motor neuron
Where is the nucleus gracilis?
The bottom of the brainstem
The nucleus cuneatus contains the second-order sensory neurons for the ____________ and is lateral to the ___________.
upper extremities; nucleus gracilis in the brainstem
