Human brain

Question 1

What is the name of the connection between wernickes and broca’s areas?

Answer 1

Arcuate fasiculus.

Question 2

How many layers of the allocortex are there?

Answer 2

3

Question 3

What are the layers of the neocortex and what do they do?

Answer 3

1. Molecular, was important in development
2. External granular,sensory input from the brain (association and commissural afferents)
3. External pyramidal (10-40 um), sends info to other parts of the brain (association and commissural fibres.
4. Internal granular, receives input from the periphery (specific afferent)
5. Internal pyramial, (betz cells 60-120um), motor signals to the periphery (projection fibres).
6. Multiform, mixture

Question 4

What does the VA VL region of the thalamus do?

Answer 4

Motor planning, sends to the motor planning part of cortex. Can receive info from the the cerebellum and basal ganglia.

Question 5

Whats the VPL and VPM regions of the thalamus do?

Answer 5

Receives sensory info from the periphery and sends it to the primary somatosensory cortex.

Question 6

Where in the thalamus doe visual and auditory info go?

Answer 6

The lateral and medial geniculate bodies, respectively.

Question 7

What does the anterior nuclear group of the thalamus do?

Answer 7

Is part of Papez’s circuit. Joins the limbic system (flight and fright) with the frontal cortex (can override limbic system)

Question 8

What do the medial and lateral nuclear groups of the thalamus do?

Answer 8

Integrates sensory input from the association corticies.

Question 9

What is the name of the dorsal funiculus and where does the info come from?

Answer 9

Gracile, legs

Cuneate, arms

Question 10

What is the name of the gaps at the anterior and posterior spinal cord?

Answer 10

Posterior median sulcus

Ventral median fissure

Question 11

What is the name of the first 3 rexted lamina?

Answer 11

Posteromarginal nucleus
Substantia gelatinosa
Nucleus proprius

Question 12

Draw where the spinal neurons go an the tracts the follow to and from the brain.

Answer 12

Page 23.
Lateral corticospinal tract (motor, 85%), ventral corticospinal tract (motor 15%)
Dorsal spinocerebellar tract, from dorsal nucleus of clark (proprioception).
Ventral spinocerebellar tract, from lamina 7
Lateral spinothalamic tract, pain and temp.

Question 13

What are the functions of the superior and inferior calliculus?

Answer 13

Detection of visual and auditory stimuli, respectively.

Question 14

What is the pathway for discriminative touch info from the arm to reach the primary somatosensory cortex?

Answer 14

Goes into the dorsal root ganglion, into the dorsal funiculus, up into the cuneate nucleus in the brainstem, a new neuron crosses over internal arcuate fibres, which go to the medial lemniscus and to the VPL region of the thalamus. It then enters the internal capsule at the posterior arm and travels to the arm region of the primary somatorysensory cortex.

Question 15

What structures make up the striatum?

Answer 15

The cordate nucleus (in the lateral ventricle) and the putamen

Question 16

What structures make up the basal ganglia?

Answer 16

Globus pallidus (internal and external), putamen, caudate nucleus, subthalamic nucleus, subsantia nigra

Question 17

What are the structures going from the cortex to the thalamus from the side?

Answer 17

Insular cortex > extreme capsule > claustrum > external capsule > putamen > external globus pallidus > internal globus pallidus > internal capsule > thalamus

Question 18

Describe parkinson’s disease and how the basal gnglia fits in.

Answer 18

Symptoms: emotionally flat, bradykinesa, tremor at rest, rigidity
Cause: there is a loss of dopamine cells in the substania nigra pars compacta, resulting i depletion of dopamine in the striatum. Less firing of the direct pathway, which initiates movement.
Treatment: levodopa, ablation of cells in an area the internal capsule on one side or in the thalamus, deep brain stimulation.

Question 19

Describe huntingtons disease and how the basal ganglia fits in.

Answer 19

Symptoms: cognitive/behavioural changes, hyperkinesia, involuntary movements.
Cause: Loss of GABAergic neurons in the striatum. Loss of the indirect pathway, which helps prevent unwanted movements.

Question 20

Describe the direct and indirect pathways in the basal ganglia.

Answer 20

Direct initiates movement and the indirect reduces unwanted movement.

Question 21

Name the three different fibre sections of the cerebellum and the fibres they contain.

Answer 21

Neocerebellum, contains pontocerebellar fibres and olivocerebellar fibres
Paleocerebellar fibres, contain spinocerebellar fibres and olivocerebellar fibres
Archicerebellum, contains vestibulocerebellar fibres and olivocerebellar fibre.

Question 22

Name the deep cerebellar nuclei and the regions they get fibres from.

Answer 22

Fastigial, paleocereellum
Interpositus, paleocerebellum
Denate, from neocerebellum (pontocerebellar fibres)

Question 23

What are the four paths from the cerebellum?

Answer 23

1) From the archicerebellum to the lateral vestibular nucleus to lower motor neurons (vestibulo spinal pathway). Involved in balance and alignment with the world).
2) from the Paleocerebellum to the fastigial nucleus to either the lateral vestibular nucleus as above or to the reticular formation to the lower motor neurons (reticulospinal fibres). Involved in control of antigravity muscles.
3) From the paleocerebellum to the interpositus nucleus to the red nucleus to the lower motor neurons (ruberospinal nucleus). Involve in posture basic functions.
4) From neocerbellum to dentate nucleus to red nucleus to thalamus to upper motor neurons to LMN. Fine motor control.