Function of the Basal Ganglia, thalamus, Limbic system, cerebral cortex methods of examination of the central nervous system.

1. Name: Gustavo Duarte Viana
Group number:17
Teacher: Okzana Zotova

2. Function of the Basal Ganglia, thalamus,
Limbic system, cerebral cortex methods of
examination of the central nervous system
Kursk, Russia
2012

3.  The basal ganglia compodes of:
consist of corpus striatum ( caudate nucleus and putamen ),
globus palidus, substantia nigra and subthalamic nucleus.
located in lateral to the thalamus.
 Function of the basal ganglia.
Executing pattern of motor activity.----- putamen circuit.
> To function in association with the corticospinal system to
control complex patterns of motor activity. ------ writing of
alphabets.
> Controlling relative intensities of sequential movements,
direction of movements and sequential of multiple movements.

4.  Motor control
 Learning
 Sensorimotor integration
 Reward
 Cognition

7.  Interconnecting circuitry through these nuclei
 These circuits start from the cortex and ends
in the cortex
 These circuits are very complex
 Their effect is excitatory or inhibitory on
motor functions (depending on the
neurotransmitter involved)
 They also have a role in cognitive functions.

8.  This circuit functions to control complex
patterns of movement in association with the
motor cortex
 eg.
◦ writing letters of alphabet,
◦ cutting papers with scissors,
◦ hammering nails,
◦ passing a football,
◦ vocalisation

9. Cortex
Thalamus
Putamen
globus
pallidus

10.  Starts from all parts of the Cx: frontal,
parietal, occpital, temporal. and association
Cx
 Then to caudate nucleus
 Then to globus pallidus
 Then to thalamus
 Finally to Premotor Cx, SMA
 This circuit functions in the cognitive control
of movement.

11. Cortex
Caudate
Thalamus
globus
pallidus

12.  Some of these circuits are excitatory and
some inhibitory
 This depends on the neurotransmitter
involved.
 Inhibitory: dopamine and GABA
 Excitatory: Ach
 Others: glutamate (from cortical projections)
enkephalin etc

13.  Lesions of the substantia nigra lead to the common and
extremely severe disease of rigidity, akinesia, and tremors
known as Parkinson’s disease.
 lesions in the globus pallidus frequently lead to spontaneous
and often continuous writhing movements of a hand, an arm,
the neck, or the face—movements called athetosis.
 Multiple small lesions in the putamen lead to flicking
movements in the hands, face, and other parts of the body,
called chorea.
 A lesion in the subthalamus often leads to sudden flailing
movements of an entire limb, a condition called
Hemiballismus.
 Basal ganglia disorders are also called extrapyramidal disorders

14.  Function of thalamus.
> Is a switchboard where all the sensory
board lead except olfactory.
> Kind of gate of the way of cerebral cortex
through which all info passes from receptors
of external and internal environment of org.
> Highest pain center.

15.  Non-specific thalamic nuclei.
-fibers give of many branches in various areas of cortex
-large number of cortical neuron in excitatory process.
-nuclei send signals to subcortical nuclei through which impulses
convert to diff. Parts of cortex.
-take part in quick and short activation of cortex.
-nuclei organize the attention process in working organism.
-have wide reciprocal connection with the relay and association
nuclei.
 Specific thalamic nuclei.
-fibers terminate in the 3rd and 4th layer of cortex and form
synapses with a limited number of cells in sensory and
associative area.
-divided in 2 groups:
> Relay nuclei
> Association nuclei
-relay nuclei receive impulses from definite sensory tract.
-association nuclei from relay nuclei.

16.  division of specific thalamic nuclei.
-principle nuclei are anterior, ventrolateral, post-ventral, lateral and medial
geniculate bodies.
-anterior thalamic nuclei – receive impulses from olfactory receptors,
viscerareceptor and transmit to limbic.
-ventralateral nucleus receive from cerebellum and transmit to motor area.
-post ventral nuclei receive from skin, face, trunk, extremities and send to
somatosensory area.
-lateral geniculate bodies for visual signs. Receive from primary visual
centers and send to visual area of cerebral cortex.
-medial geniculate bodies for auditory tract. Receive from primary auditory
centers and send to auditory cortex.

17.  Association thalamic nuclei.
-located in anterior and receive impulses from relay nuclei and
send them to associative area of cortex.
-include lateral, dorsomedial, and pulvinar nuclei.
-lateral nuclei send impulses to parietal region of cortex.
-lateral part of pulvinar nuclei send to optic associative area in
occipital lobe.
-medial part of pulvinar nuclei to the auditory associative area of
temporal lobe.
-dorsomedial nuclei connected with cortex of the frontal lobe with
limbic system and hypothalamus.

18.  Structure of the limbic system.
-limbic system is entire neuronal circuitry that controls
emotional behaviour and motivational drives and
internal condition of body.
-major part is the hypothalamus.
-central is the hypothalamus and surrounds are other
subcortical structure of limbic system ----- septum,
anterior nuclei of thalamus, basal ganglia,
hippocampus, amygdala and parolfactory area.
-surrounding subcortical limbic is limbic cortex
compose of a ring------- orbitofrontal cortex,
subcallosal gyrus, cingulated gyrus, parahippocampal
gyrus and uncus.

20. vegetative functions:
> Cardiovascular regulation
- excitation can cause increase and decrease of arterial pressure, heart rate
- stimulation in posterior and lateral hypothalamus cause increase in arterial pressure and heart rate
- stimulation in preoptic area (anterior) cause decrease.
- Transmitted mainly through cardiovascular control center.
> Regulation of body temperature.
- preoptic area (anterior)
- an increase and decrease of temperature of blood flowing through this area sense the charges.
> Regulation of body water - in 2 ways:
1. by creating the sensation of thirst---- thirst centers in lateral hypothalamus.
-when electrolyte inside neuron become too concentrated, cause desire to drink.
2. by controlling the excretion of water into urine.
-control in supraoptic nucleus
-when body fluid become too concentrated, the neuron become stimulated.
-posterior pituitary gland secre ADH.
-cause reabsorption.
> Regulation of uterine contractility and milk ejection by breast.
- stimulation of paraventricular nucleus secrete oxytocin.
- Cause contractile of uterine and milk ejection.
> GI and feeding regulation.
1. hunger ---- lateral hypothalamus area
2. satiety center ---- ventromedial nucleus
3. mammilary bodies ---- feeding reflexes such as licking the lips and swallowing.

21. > in anterior pituitary gland, releasing and
inhibitory hormones are secreted into blood
> hormone transported to ant pituitary gland, and
act on glandular cells.
> Cell bodies tht secrete this hormones located in
medial basal nuclei of hypothalamus especially in
periventricular zone, arcuate nucleus and part of
ventromedial nucleus.
> These axons project to median eminence.
> Here secretion of inhibitory and excitatory
hormone take place.

22. Reward center
- lateral and ventromedial nuclei of hypothalamus (main)
- secondary cemters are septum, amygdala, certain area of thalamus and basal
ganglia and extending downward into basal tegmentum of mesencephalon.
Punishment center
- in central gray area surrounding the aqueduct of Sylvius in mesencephalon and
extending upward into periventricular zones of hypothalamus.
- Less --- amygdala and hippocampus.
- Can take preceding over reward centers.
-if no reward and punishment, repetition of stimuli will cause habituation and
therefore will cause the animal to ignore it.
-if got reward and punishment effect, stimuli will be reinforced and animal will build
up strong memory trace.
-so this 2 effect are important in learning and memory.
-so selection of information do take place.

23. Function of hippocampus.
-any type of sensory activate hippocampus and its
distribute to anterior thalamus and
hypothalamus.
> Additional channel through which incoming
sensory signals lead to appropriate behavior.
> Hippocampal also hyperexcitable ---- give
prolonged output signals even under normal
condition.
> Important in learning new information and
prevent anterograde amnesia.
> Important in reward and punishment process --
- can transfer short term memory into long term.

24. Fuction of the amigdala
receive neuronal signals from all limbic cortex, neocortex
esp visual and auditory.
effect of stimulating amygdala :
Regulate arterial pressure, heart rate, GI motality and
secretion, defecation and micturation, pupillary dilationa
nd constriction, piloerection etc
-also involving involuntary movement:
> Tonic movement, circling, rhythmic, licking, chewing and
swallowing.
-also stimulate sexual activities ---- destruction will cause
Kluver-Bucy syndrome.

25.  -poorly understood
 -function as transitional zone through which
signals transmitted from cortex into limbic
system.
 -functional as cerebral association area for
control of behaviour.
 -if damage can cause,, --- kluver-bucy
syndrome, development insomnia, motor
restlessness,
 - so cortex mainly as intermediate associative
positions between function of cerebral cortex
and limbic system.

26.  The cerebral cortex is divided into
Archiocortex: include the olfactory bulbes
which receive afferentation from olfactory
epithelium, olfactory tracts and olfactory
tubules
Paleocortex: comprises the gyrus cinguli,
Hyppocamal gyrus and amygdala
Neocortex: include all the other regions

27. In the cerebral cortex is present sex layers
1 Molecular layer
2 External granular layer
3 External pyramidal layer cells
4 Internal granular layer
5 Internal pyramidal layer cells
6 Fusiform or polymorphic cells

29. -anterior to central sulcus, posterior 1/3 of frontal
lobes.
divided into:
A. primary motor cortex-controlling hand & speech
musle
B. premotor area-control of body’s complex pattern of
coordinated muscle activity
C. supplementary area-bilateral movement,fine motor
control
D. Specialized area: 1.Broca’s area & speech
2.voluntary eye movement
field
3.head rotation area
4. area for hand skills

30. -posterior to central sulcus
-anterior half of parietal, concerned with reception & interpretation
posterior with higher level of interpretation of sensory signals
-divided into
A. somatosensory areas I
-representation of specific sensory sensation
-judgment of pressure, weight, shapes & texture
-appreciation of spatial relationship (space localization, higher degree of sensation
>B. somatosensory areas II
-have no good localization of body portion
-transmit signal from brain stem, primary sensory area & visual @ auditory area to
secondary somatic area
-each side of cortex receives sensory information from opposite side of body
-representation of sound & discrimination mainly present in temporal lobe
-perception of taste-involve large area of temporal cortex & insula
-destruction of this area: reduce ability to discriminate btw flavors

31. >localization: in parietal & occipital cortical; anterior-somatosensory posterior-visual
cortex
>general function: provide high level of interpretive meaning for signal from surrounding
sensory area
>functions :
I) analysis of spatial coordination
#Localization: begin in parietal cortex, extending into superior occipital cortex,
provides continuous analysis of spatial coordinates of all body parts & surrounding of
body
#receive ~visual sensory information from post occipital cortex
~simultaneous somatosensory information from anterior parietal cortex
thus, computes of visual, auditory & body surrounding
II) area for language comprehension=Wernicke’s area
#localization:behind primary cortex in posterior part of superior gyrus of temporal
#function:higher intellectual information( intellectual function is language based)
III) area for initial processing of visual language(reading)
#localization: posterior to language comprehension area, in angular gyrus
#function: >make meaning out of visually perceived words
>in its absent, will have excellent language comprehension through hearing
but not through reading
IV) area for naming objects @ word formation
#localization: most lateral of both anterior occipital lobe & posterior temporal lobe.
#function: >naming of objects
>names are learned through auditory input
>physical natures learned through visual input

32. >prefrontal function in close association with motor cortex to plan complex pattern
& sequences if motor movement
>provides sequential & parallel movement
> carry out thought processes in mind
plan motor activity capable of processing non-motor & motor information
thus, achieving non motor & motor types of thinking.
important for elaboration of thoughts- store short term basis ‘working
memories’ that used to analyzed new thoughts when entering brain.
> Broca’s area: localization-partly in posterior frontal cortex, premotor area
functions- provide neural circuitry for word formation
plans & motors patterns for expressing individual words, phases
are initiated & executed
work with Wernicke’s area

33. >localization: anterior of temporal lobe, ventral of
frontal lobe
in cingulated gyrus lying deep in longitudinal
fissure on midsurface of each cerebral hemisphere
>functions:+behavior, emotion, motivation
+provide emotional drives for setting other
area of brain into action & provides motivating drive
for process of learning
+recognition of faces
emotion= individual psyche reaction which
related to reward & punishment center ; important for
social life & communication
motivation= arise from positive aim to
maintain homeostatic parameter

34.  It is a special region in the frontal cortex,
providing the neuronal circuit for word
formation.
 Play the motor pattern for the expressing
individual words or even short phrases can be
excuted.

35.  General interpretative area, knowing area,
tertiary association area.
 It plays the greatest single role in any part of
cerebral cortex in the high comprehensive
levels of the brain functions that we call
intelligence and it interpreting the
complicated meanings afferent patterns of
the sensory experience.

37.  the general interpretative function of the
wernicke’s area and angular gyrus as well as
the function of the speech and the motor
control areas usually are much more
developed in one hemisphere then in the
other one
 95% of the human population has the left
dominant hemisphere

40.  Methods of investigation of the electrical activity of brain.
 Electroencephalograophy, it’s role in medicine:
a) To detect problems and compare with standards
b) To find out the localisation of problem, used for correction
c) Record EEG changes during sleep
d) Determine electrical activity of brain-stressed, relaxed
 Steretaxic method: To investigate coordinates/localisation of diff.
points/ portions of brain.
 Determine:
a)The A-A horizontal plane which passes through the centres of the
external auditory meatus and the inferior points of the orbital margins.
This is called the ‘principal horizontal line’ and used for reading
stereotaxic coordinates.
b)O-horrizontal line, 1cm above A-A hori.line
c)O-frontal plane, lying along the line connecting the centres of the ext.
Auditory meatus and perpendicular to the horizontal plane.
d)O-sagital plane, lying in the medius sagital cranial line, perpendicular
to the horizontal and frontal planes.

42. Thank you for
attention