The frontal lobe of the cerebrum is separated from the temporal lobe by the _____.
One can see that three sulci demarcate 2 vertical gyri at the interface of the _____ and _____ lobes.
- Parietal
From anterior to posterior, the sulci are the precentral sulcus, the _____, and the postcentral sulcus.
The central sulcus separates the _____ from the _____.
- Parietal lobe
The precentral gyrus is between the _____ and the _____.
- Central sulcus
The primary motor cortex (Brodmann area 4) occupies the precentral gyrus which is the only vertical gyrus of the _____.
The primary motor cortex (Brodmann area 4) contains the _____ neurons for voluntary motor activity.
The giant motor neurons of the primary motor cortex (Brodmann area 4) are the same size as Purkinje cells (100 um across), but they are pyramidal instead of _____.
Giant pyramidal neurons (Betz cells) are found only in the _____.
Brodmann defined area _____ as the area of the cerebral cortex containing giant pyramidal neurons.
The axons of the giant pyramidal neurons descend in the lateral and anterior _____ tracts and synapse on lower motor neurons.
The only axons in the corticospinal tracts that synapse on the dendrites and bodies of lower motor neurons are the axons of _____.
The axons of the large (not giant) pyramidal neurons of the primary motor cortex also descend in the _____, but they synapse on internuncial neurons that synapse on lower motor neurons.
The giant pyramidal neurons (100 um across) of Brodmann area _____ are almost twice as large as the large pyramidal neurons (60 um across).
The axons of giant pyramidal neurons synapse on _____, but the axons of the more numerous large pyramidal neurons synapse on _____.
- Internuncial neurons
Both kinds of _____ are somatotopically arranged with neurons controlling the larynx at the inferior end of the precentral gyrus.
The upper motor neurons controlling the tongue are superior to neurons controlling the larynx in the _____ gyrus.
Upper motor neurons controlling the facial muscles are superior to neurons controlling the tongue in the _____.
_____ controlling fingers are arranged in an ascending 1-5 sequence from the _____ for the facial muscles.
- Upper motor neurons
Upper motor neurons for the arm are _____ to the upper motor neurons for the fingers and _____ to upper motor neurons for the trunk. which occupy the peak of the precentral gyrus.
- Inferior
Upper motor neurons for the _____ are in a descending thigh-calf-foot sequence on the part of the precentral gyrus inside the longitudinal fissure.
On the motor homunculus below, each body part of the homunculus is positioned next to the region of the precentral gyrus containing the _____ neurons controlling that part.
The motor homunculus for a precentral gyrus has only half of a body because the left motor cortex controls only the _____ side of the body.
The disproportionate amount of space in the _____ devoted to the upper motor neurons for the _____ reflects number of neurons necessary to achieve fine motor control of the _____.