Thalamus

Question 0

Motor specific nuclei of thalamus (2)

Answer 0

Ventral lateral (VL)
Ventral anterior (VA)

Question 1

Sensory specific nuclei of thalamus (4)

Answer 1

Ventral posterolateral  (VPL)
Ventral posteromedial (VPM)
Lateral geniculate (LGN)
Medial geniculate

Question 2

Association nuclei function: (3)

Answer 2

1. Connect w/ association cortical areas
2. Receive input from many other thalamic nuclei
3. Connections w/ cortex that are not directly reciprocal

Question 3

Association specific thalamic nuclei (2)

Answer 3

Mediodorsal nucleus

Pulvinar

Question 4

Limbic specific nuclei

Answer 4

Anterior group (AN)
Laterodorsal nucleus (LD)

Question 5

Non-specific thalamic nuclei

Answer 5

Midline nuclear group
Intralaminar group (centromedian nucleus)

Question 6

Ventral posterolateral nucleus
Input:
Output:

Answer 6

Input: Spinothalamic = pain/temp, DCML = discriminative touch

Output: Reciprocally connected w/ postcentral gyrus (limb and trunk of somatosensory cortex)

Question 7

Ventral posteromedial nucleus (VPM)
Input:
Output:

Answer 7

Input:
Trigeminothalamic system: sensory from face
Taste from NTS via dorsal longitudinal fasciculus –>Medial, parvicellular portion of VPM (VPMpc)

Output:
VPM: Face portions of somatosensory cortex (postcentral gyrus)
VPMpc: anterior part of insula (primary gustatory cortex)

Question 8

Lateral geniculate nucleus (LGN)
Input:
Output:

Answer 8

Input: Visual (optic tract) of contralateral visual field
Output: Primary visual cortex (V1) in occipital lobe (cuneus and lingual gyrus) via optic radiation

Question 9

Lateral geniculate nucleus

Magnocellular projections from layers ___ and ___ convey info about ____ from ____

Answer 9

Layers 1 and 2
Movement, depth and small differences in brightness
Retinal rods

Question 10

Lateral geniculate nucleus

Parvocellular projections from layers ___ to ___ convey ____ from ____

Answer 10

Layers 3-6
Fine details about form and color
Retinal cones

Question 11

Inputs from temporal retina end (ipsilateral) end in layers ___

Answer 11

2, 3, 5

Question 12

Inputs from nasal retina end (contralateral) end in layers ___

Answer 12

1, 4, 6

Question 13

Medial geniculate nucleus
Input:
Output:

Answer 13

Input:
Auditory input from inferior colliculus

Output:
Auditory cortex in Heschl’s gyrus of temporal lobe via auditory radiations

Question 14

Ventral lateral nucleus (VL)
Input:
Output:

Answer 14

Input:
Crossed output of cerebellar deep nuclei via thalamic fasciculus

Output:
Primary motor cortex in precentral gyrus

Question 15

Ventral anterior nucleus (VA)
Input:
Output:

Answer 15

Input:
Inhibitory input from ipsilateral basal ganglia via thalamic fasciculus

Output:
Lateral part: trunk and limb regions of premotor cortex
Medial part: premotor, frontal eye fields, cingulate and parietal cortices

Question 16

Lateral part of ventral anterior nucleus (VA) receives input from:

Answer 16

globus pallidus internal segment (GPi)

Question 17

Medial part of ventral anterior nucleus (VA) receives input from:

Answer 17

Sustantia nigra pars reticulata (SNr)

Question 18

Thalamc fasciculus is a composite bundle containing _____ fibers that is insinuated between ____ and ___.

Answer 18

Cerebellothalamic (Crossed)
Pallidothalamic (Uncrossed)

Thalamus, zona incerta

Question 19

Basal ganglia disease on motor function are expressed (ipsilaterally/contralaterally)

Answer 19

Contralaterally

Question 20

Cerebellar disease are expressed (ipsilaterally/contralaterally)

Answer 20

Ipsilaterally

Question 21

Mediodorsal nucleus (MD)
Input:
Output:
Function:

Answer 21

Input:
Amygdala, olfactory cortex, ventral pallidum (basal forebrain)
Output:
Prefrontal cortex and limbic system
Function:
Attention, planning, organization, abstract thinking, multitasking, active memory

Question 22

Lesions affecting mediodorsal nucleus results in ____

Answer 22

apathy
memory changes
difficulty in switching tasks

Question 23

Pulvinar
Input:
Output:
Function:

Answer 23

Input:
Retina, superior colliculus, spinothalmic tract (indirectly)
Output:
Parietal, temporal, occipital lobes
Function:
Language processing, visual perception, pain perception

Question 24

Anterior group (AN) Input: Output: Function:

Answer 24

Input: Para-hippocampal region via fornix and mammillary bodies (mammillothalamic tract) Cholinergic input from midbrain Output: Cortex of cingulate gyrus

Question 25

Laterodorsal nucleus (LD) Input: Output: Function:

Answer 25

``` Input: Parahippocampal region via fornix Output: Parietal cortex, retrosplenial cortex Function: Spatial learning and memory ```

Question 26

Korsakoff's syndrome caused by:

Answer 26

Severe degenerative changes in anterior group | Changes in mammillary bodies

Question 27

Spatial and context-dependent memory formed from distributed neural system made from: (6)

Answer 27

anterior group, laterodorsal nucleus, mammillary bodies, fornix, mammillothalamic tract, cingulate and retrosplenial cortices

Question 28

Midline nuclear group Input: Output: Function:

Answer 28

Input: Pain-related info from midbrain PAG Cholinergic elements of Ascending Reticular Activating System Locus ceruleus (NE) and midbrain raphe (5-HT) Output: Diffusely to cortex and striatum Thalamic paraventricular nucleus connected w/ suprachiasmatic nucleus Function: General cortical arousal

Question 29

Intralaminar group (centromedian nucleus) Input: Output: Function:

Answer 29

``` Input: non-reciprocal input from motor cortex Cholinergic input from ARAS Output: Reciprocally connected w/ striatum and basal ganglia Function: Attention to motor tasks ```

Question 30

Lesions of centromedian nucleus lead to ____

Answer 30

Unilateral motor neglect

Question 31

Thalamic relay neurons on burst mode are ____ | Function:

Answer 31

Hyperpolarized, "de-inactivated" | Less able to pass incoming signal to cortex BUT maximized initial stimulus detection

Question 32

Thalamic relay neurons in tonic mode are ____ | Function:

Answer 32

Depolarized | Better linear summation (pass signal to cortex) BUT poorer detectability for new stimuli

Question 33

Function of intralaminar thalamic cells

Answer 33

Hyperpolarize thalamic relay neurons via GABAb receptors --> primed for bursting activity

Question 34

Switch between burst mode and tonic mode is controlled by ___

Answer 34

Modulatory afferents to these cells = thalamic reticular nuclei (TRN) + feedback pathway from cortex

Question 35

Thalamic reticular nuclei (TRN) are innervated by ____ | Involved in:

Answer 35

Cholinergic fibers of ARAS from midbrain Coordinating information traffic from relevant sensory channels

Question 36

During slow-wave sleep, TRN keeps all thalamocortical neurons in ____ mode

Answer 36

burst --> can't pass signals

Question 37

During wakefulness, TRN _____

Answer 37

selectively switches populations of relay neurons from burst to tonic mode

Question 38

Blood supply to thalamus is mostly from ____

Answer 38

Posterior cerebellar artery

Question 39

Infarct in inferolateral a. (branch of PCA) will cause (4):

Answer 39

Ataxia Hemiparesis Hemianesthesia Hemihyperesthesia

Question 40

Infarct in the paramedian a. will cause (3):

Answer 40

Hemiparesis (motor neglect) Memory/learning problems Apathy

Question 41

Infarct in anterior (tuberothalmic) a. will cause (3):

Answer 41

Amnesia Language difficulty Euphoria/mood

Question 42

Contralateral hemianesthesia caused by:

Answer 42

VPL/VPM damages

Question 43

Contralateral hemianopsia (blindness) caused by:

Answer 43

Lateral geniculate nucleus (LGN) damage

Question 44

Contralateral hemichorea caused by:

Answer 44

VA/VL damage

Question 45

Contralateral hemitremor and hemiataxia caused by:

Answer 45

VL damage

Question 46

Retrograde/anterograde amnesia caused by:

Answer 46

MD, midline nuclei

Question 47

Dejerine-Roussy Syndrome characterized by: (5)

Answer 47

``` Hemi-ataxia Hemi-tremor Hemi-chorea Hemi-anesthesia 2 pt touch Hyperesthesia: exaggerated pain and temp. ```