DSA: General Terminology & SC Morphology
What are 5 different names for white matter?
1. fasciculus 2. funiculus 3. leminscus 4. peduncle 5. tract
What are the 4 functions of the temporal lobe?
1. primary auditory cortex (w/in superior temporal gyrus) 2. Wernicke's area, language comprehension (posterior portion superior temporal gyrus) 3. higher order processing visual info 4. learning and memory (medial part)
How are tracts of white matter named?
1st part: loc of neuronal cell bodies from which axons originate 2nd part: loc of axon termination
Where is the fusiform gyrus located?
AKA Occipitotemporal gyrus - inferior temporal lobe
What are the similarities and differences between the fasciculus cuneatus (FC) and Fasciculus Gracilis (FG)?
BOTH: bundles of axon fibers in the posteiror column medial leminscus pathway BOTH: Ascending tract relay info to the brain via SC FC: carries sensory info from arms FG: carries sensory info from midthoracic & lower limbs
Describe the course of CSF flow through the ventricles in the brain
Lateral ventricles → interventricular foramen (foramen of Monro) → 3rd ventricle → cerebral aqueduct (aqueduct of Sylvius) → 4th ventricle → central canal
What type of neurons can be found in the intermediolateral cell column and what spinal segments contain it?
Pre-Ganglionic sympathetic neurons T1-L3
What is the meaning of a homunculus?
a map which is spatially distorted & reflects the amount of innervation to a given body area
What is the uncus?
a medial bump formed by the parahippocampal gyrus
The 3 lobes of the cerebellum receive affarent information. What are the lobes and where do they receive info from?
anterior - spinal cord (trunk and limb movements) flocculonodular lobe - vestibular system (eye movement and postural adjustment to gravity) posterior - cerebral cortex via pons (voluntary movements)
What commissure connects commissural fibers to/from the temporal lobe?
anterior commisure
Where is the amygdala located?
beneath the uncus of the temporal lobe
Where is the insula of the brain found? and what feature surrounds it?
buried in the lateral sulcus surrounded by circular sulcus
Name the 4 prominent sulci that divide the brain into 5 lobes
central sulcus lateral sulcus ("Sylvian Fissure") parietooccipital sulcus cingulate sulcus
What 2 gyri is the limbic lobe composed of?
cingulate & parachippocampal gyri
What are commissural tracts?
connect cortical areas within R/L hemispheres
What are projection tracts?
connect cortical areas within other body regions
What are longitudinal/association fasciculi?
connect cortical areas within the same hemisphere
What are arcuate fibers?
connect cortical areas within the same sulci/gyri
What is the main job of the hypothalamus?
control of the autonomic nervous system (regulates visceral responses, temp, and some limbic function)
The anterior horn is responsible for what type of info transmission?
control over body movements
What huge fiber bundle joins the 2 hemispheres of the brain?
corpus callosum
What is the function of the limbic lobe?
emotional responses, drive-related behavior & memory
What brain functions are controlled by the prefrontal cortex?
executive functions, personality, decision making, insight & foresight
What is the term for the thin strand of pia mater that helps anchor the conus medullaris to the coccyx?
filum terminale
What are the lobes of the brain?
frontal parietal occipital temporal limbic
What is the difference between gray matter and white matter?
gray: areas containing neuronal/glial cell bodies & dendrites white: areas where there is a collection of axons, many covered in myelin
Where is the lingual gyrus?
inferior to the calcarine sulcus (usually continuous with parahippocampal gyrus)
What function is associated with the inferior parietal lobule? (one hemisphere, usually left)
language comprehension
What is Clark's nucleus?
posterior thoracic nucleus found in the medial surface of the base of the posterior horn (T1-L2) *prominent role in sensory processing*
Where is the primary motor cortex found in the brain?
precentral gyrus
Where are the premotor & supplementary motor areas found?
precentral gyrus, posterior portions of superior & middle frontal gyri
What is the main job of the thalamus?
relaying information to the cerebral cortex
Corresponding to the same location as the IML, S2-S4 contains what structure?
sacral parasympathetic nucleus
What structure separates the lateral ventricles of the brain?
septum pellucidum
The posterior horn of the spinal cord is responsible for transmission of what type of info?
somatic and visceral sensory
What is the term for the region of gray matter in the spinal cord that caps the posterior horn?
substantia gelatinosa appearance: pale bc. finely myelinated/unmyelinated sensory fibers that carry pain & temp info
What are the 4 divisions of the diencephalon?
thalamus hypothalamus epithalamus subthalamus
Describe the layout of the basal nuclei and subdivisions
the caudate and lenticular nucleus (subdivided into putamen & globus pallidus) separated by the internal capsule
Where is the visual association cortex found?
the occipital lobe
Where is Broca's area found?
the opercular & triangular parts of the inferior frontal gyrus
Where is the primary somatosensory cortex found?
the postcentral gyrus
What is the term for the midline of the cerebellum?
vermis
What is the cuneus and where is it found?
wedge-shaped area between parietoocipital & calcarine sulci
What is Lissauer's tract?
white matter between substantia gelatinosa & the surface of the cord
Where is the primary visual cortex found?
within the walls of the calcarine sulcus
Differentiate the laminae (1-10) of the spinal cord gray matter
• Lamina I (marginal zone): is a thin layer of gray matter covering the substantia gelatinosa • Lamina II: is the substantia gelatinosa • Laminae III through VI: are the body of the posterior horn • Lamina VII: corresponds to the intermediate gray matter (including Clarke's nucleus), but also includes extensions into anterior horn • Lamina VIII: comprises some of the interneuron zones of the anterior horn • Lamina IX: consists of the clusters of motor neurons embedded in the anterior horn • Lamina X: is the zone of gray matter surrounding the central canal
