prosencephalon (forebrain)- telencephalon

Question 1

what are the 3 parts of the telencephalon?

Answer 1

• outer gray cerebral cortex- pallium
• mass of white fibers- centrum semiovale
• deep in white matter- neuron cell bodies called basal ganglia

Question 2

telencephalon has 4 lobes on each side

Answer 2

frontal, temporal, parietal, occipital

Question 3

the insula (isle of reil) and limbic region are sometimes called?

Answer 3

lobes and pseudolobes

Question 4

general functions of the telencephalon?

Answer 4

• final integration of neural mechanisms
• initiation center for voluntary actions
• memory and associative memory
• abstract thinking- prefrontal- broadmann 9 through 12

Question 5

what is the surface area of the cerebral cortex/pallium?

Answer 5

2.5 square feet- 2/3 of area is down in the sulci

Question 6

in most areas the gyrus sulcus is ____ than the sulcus cortex?

Answer 6

thicker

Question 7

what are the 2 subdivisions of the cerebral cortex/pallium?

Answer 7

neocortex- 90% of total cortex- cells and cell layers homogenous
allocortex- 2 parts (olfactory and hippocampal) heterogenous

Question 8

what are the 6 common laminae of the neocortex? arranged external to internal

Answer 8

molecular lamina I- lots of synapses 
external granular lamina II
external pyramidal lamina III
internal granular lamina IV 
internal pyramidal lamina V
multiform lamina VI

Question 9

the molecular layer is which layer?

Answer 9

outermost and nearest to pia mater; filled with synaptic activity

Question 10

describe external granular layer- II

Answer 10

small, closely packed granular neurons
axons extend into deeper lamina of same cortex area
intracortical association layer

Question 11

describe the external pyramidal layer- lamina III

Answer 11

small pyramidal shaped neuron cell bodies
axons extend out of cortex to white matter and then return to gray matter
-projection, association and commissural fibers
intercortical association layer

Question 12

lamina II and III are also called?

Answer 12

associative lamina- best developed in human brain

Question 13

describe internal granular layer- IV

Answer 13

small closely packed cell bodies
specific thalamic inputs arrive here
well developed sensory areas (touch, pain, sight etc)

Question 14

describe internal pyramidal layer- V

Answer 14

large pyramidal- shaped neuron cell bodies
giant pyramidal Betz cells here as well
axons project to other brain and cord centers from here

Question 15

describe multiform layer- VI

Answer 15

mix of incoming and outgoing fibers

large number of projection neurons- especially to thalamus

Question 16

laminae V and VI are sometimes called?

Answer 16

projection laminae

Question 17

what are the parts of the basal ganglia? all bilateral

Answer 17

caudate nucleus
putamen nucleus
globus pallidus or paleostriatum
amygdaloid complex or archistriatum

Question 18

putamen and globus pallidus together are called?

Answer 18

lenticular nucleus

Question 19

striatal lesions normally lead to?

Answer 19

dyskinesia (muscle tone disturbances)

Question 20

dyskinesia examples?

Answer 20

tremor
chorea
ballism or hemiballism

Question 21

tremors usually come from a lesion where?

Answer 21

in the cerebellum

Question 22

example of chorea?

Answer 22

huntingtons chorea- graceful involuntary movements of extremities, facial muscles, tongue etc- corpus striatum begins to deteriorate- deficiency of GABA

Question 23

ballism or hemiballism is a more violent movement and can occur from lesions where?

Answer 23

globus pallid us which communicates with subthalamic nucleus

Question 24

describe the caudate nucleus

Answer 24

has a head, body and tail

head region is continuous with the putamen nucleus by gray matter bridges

Question 25

afferent fibers of caudate nucleus synapse in the caudate from?

Answer 25

all lobes of the cortex, the thalamus, substantia nigra and putamen

Question 26

efferent fibers of caudate extend to?

Answer 26

putamen, globus pallidus, substantia nigra and thalamus

Question 27

what is the most lateral of the corpus striatal nuclei?

Answer 27

putamen nucleus

Question 28

afferent and efferent fibers of putamen are ______ as caudate?

Answer 28

the same

Question 29

the _____ is part of the lenticular nucleus along with the putamen

Answer 29

globus pallidus

Question 30

afferents of globus pallidus include axons from

Answer 30

caudate
putamen
subthalamic

Question 31

describe the efferent fibers of globus pallidus

Answer 31

primary efferent outflow from corpus striatum- anterior aspect of thalamus

Question 32

what is the ancient part of the basal ganglia located in the temporal lobe ?

Answer 32

amgydala

Question 33

inputs for the amygdala from?

Answer 33

olfactory tract, hypothalamus and neocortex

Question 34

amygdaloid activity is associated with?

Answer 34

increased inhibition- fear and anger

Question 35

what is the name for the collective white matter of telencephalon?

Answer 35

centrum semiovale

Question 36

what are the fiber types in the white matter of telencephalon?

Answer 36

projection- afferent and efferent

commissural- corpus callosum (300 million neurons)

Question 37

projection axons in the white matter utilize what?

Answer 37

corona radiata and internal capsule

Question 38

what are the different parts of the corpus callosum?

Answer 38

splenium, body, genu, rostrum, forceps anticus, forceps posticus and tapetum

Question 39

what is the most abundant part of the white matter?

Answer 39

association axon bundles (fasciculi)

Question 40

the corpus callosum is only found in?

Answer 40

placental mammals