thalamus

Question 1

Where is the thalamus located?

Answer 1

In the diencephalon, on either side of the third ventricle.

Question 2

What structure surrounds the thalamus laterally?

Answer 2

The internal capsule.

Question 3

What divides the thalamic nuclei internally?

Answer 3

The internal medullary lamina (Y-shaped white matter).

Question 4

What are the main groups of thalamic nuclei?

Answer 4

Relay, motor, limbic, association, intralaminar, and reticular nuclei.

Question 5

Which thalamic nucleus relays body somatosensation?

Answer 5

Ventral posterolateral nucleus (VPL).

Question 6

Which thalamic nucleus relays face somatosensation and taste?

Answer 6

Ventral posteromedial nucleus (VPM).

Question 7

Which nucleus relays visual input?

Answer 7

Lateral geniculate nucleus (LGN).

Question 8

Which nucleus relays auditory input?

Answer 8

Medial geniculate nucleus (MGN).

Question 9

Which thalamic nuclei are involved in motor function?

Answer 9

Ventral anterior (VA) and ventral lateral (VL).

Question 10

Which nucleus connects to the limbic system and affects emotion/memory?

Answer 10

Anterior and mediodorsal nuclei.

Question 11

What is the role of the intralaminar nuclei?

Answer 11

Modulation of arousal, pain, and consciousness.

Question 12

What is the role of the reticular nucleus?

Answer 12

Regulates activity of other thalamic nuclei.

Question 13

What are the core functions of the thalamus?

Answer 13

Sensory relay (except smell), motor integration, consciousness, emotion, pain.

Question 14

What sensory modality does not relay through the thalamus?

Answer 14

Olfaction (smell).

Question 15

What thalamic nuclei relay cerebellar and basal ganglia motor output to cortex?

Answer 15

VA and VL.

Question 16

What is the cortical target of VPL and VPM?

Answer 16

Primary somatosensory cortex.

Question 17

What is the cortical target of LGN?

Answer 17

Primary visual cortex (V1).

Question 18

What is the cortical target of MGN?

Answer 18

Primary auditory cortex (A1).

Question 19

Which imaging sequence best identifies acute thalamic infarcts?

Answer 19

DWI (Diffusion-weighted imaging).

Question 20

On MRI, how does the thalamus appear on T1-weighted images?

Answer 20

Isointense to gray matter.

Question 21

On MRI, how does the thalamus appear on T2-weighted images?

Answer 21

Hyperintense compared to white matter.

Question 22

What is seen in a bilateral thalamic infarct of the artery of Percheron?

Answer 22

Bilateral paramedian thalamic lesions on MRI.

Question 23

Which conditions commonly show bilateral thalamic signal abnormalities?

Answer 23

Leigh syndrome, Wilson disease, Fabry disease, NCL.

Question 24

What clinical syndrome results from VPL/VPM lesions?

Answer 24

Contralateral hemianesthesia ± central pain.

Question 25

What results from damage to the LGN?

Answer 25

Visual field deficits.

Question 26

What results from damage to the MGN?

Answer 26

Central auditory processing deficits.

Question 27

What results from damage to the mediodorsal nucleus?

Answer 27

Memory loss and emotional disturbances.

Question 28

What results from damage to intralaminar nuclei?

Answer 28

Decreased arousal or coma.

Question 29

A stroke in the VPL nucleus of the thalamus causes what deficit?

Answer 29

Contralateral body hemianesthesia (loss of proprioception, pain, temperature).

Question 30

A patient with facial numbness and taste disturbance likely has a lesion in which thalamic nucleus?

Answer 30

Ventral posteromedial nucleus (VPM).

Question 31

What is Dejerine–Roussy syndrome (thalamic pain syndrome)?

Answer 31

Chronic, severe contralateral pain after thalamic stroke, typically affecting the VPL/VPM.

Question 32

A sudden bilateral loss of consciousness and vertical gaze palsy suggests infarction of which artery?

Answer 32

Artery of Percheron (supplying bilateral paramedian thalami and midbrain).

Question 33

What imaging finding is characteristic of an artery of Percheron infarct?

Answer 33

Bilateral paramedian thalamic infarcts ± midbrain involvement on DWI/FLAIR.

Question 34

Which thalamic nucleus is affected in Wernicke-Korsakoff syndrome, contributing to memory impairment?

Answer 34

Mediodorsal nucleus.

Question 35

Which thalamic nucleus is disrupted in vegetative or minimally conscious states?

Answer 35

Intralaminar nuclei (especially centromedian nucleus).

Question 36

In which neurodegenerative/metabolic disorders do bilateral thalamic lesions appear?

Answer 36

Wilson disease, Leigh syndrome, Fabry disease, GM1 gangliosidosis, NCL.

Question 37

A young patient with developmental regression and symmetric thalamic hyperintensity on MRI likely has what type of disorder?

Answer 37

Lysosomal storage disease or mitochondrial encephalopathy (e.g., Leigh syndrome).

Question 38

What type of lesion is expected in hypertensive thalamic hemorrhage?

Answer 38

Unilateral hyperdense lesion on CT, commonly in the posterolateral thalamus.

Question 39

What visual field defect may result from damage to the lateral geniculate nucleus (LGN)?

Answer 39

Contralateral homonymous hemianopia.

Question 40

A patient with auditory hallucinations and temporal lobe seizures may have involvement of which thalamic relay nucleus?

Answer 40

Medial geniculate nucleus (MGN).

Question 41

What are the most common presenting symptoms of a thalamic infarct?

Answer 41

Sensory loss (hemianesthesia), pain, cognitive or language changes, and arousal disturbances.

Question 42

What thalamic nucleus is responsible for modulating cortical attention and is affected in neglect syndromes?

Answer 42

Pulvinar nucleus.

Question 43

What structure must be involved if a thalamic stroke results in aphasia?

Answer 43

Dominant hemisphere thalamus (especially anterior and pulvinar nuclei).

Question 44

What MRI finding suggests thalamic glioma?

Answer 44

T2 hyperintense, often enhancing mass with or without calcification; may involve bilateral thalami in diffuse gliomas.

Question 45

What is the likely diagnosis in a child with startle seizures, developmental delay, and bilateral thalamic calcifications?

Answer 45

Neuronal ceroid lipofuscinosis (NCL).

Question 46

Which thalamic nucleus regulates sleep-wake cycles and generates sleep spindles on EEG?

Answer 46

Reticular nucleus.

Question 47

How does the thalamus contribute to epilepsy?

Answer 47

It acts as a pacemaker in generalized seizures by corticothalamic-cortical feedback loops.

Question 48

In deep coma following trauma or stroke, what thalamic structure is often implicated?

Answer 48

Bilateral involvement of the intralaminar nuclei.

Question 49

A 6-month-old with developmental delay and symmetric T2 hyperintensity in the thalami likely has what condition?

Answer 49

Leigh syndrome (mitochondrial disorder).

Question 50

A child with regression, seizures, vision loss, and thalamic calcifications on CT likely has what disorder?

Answer 50

Neuronal ceroid lipofuscinosis (NCL).

Question 51

What MRI finding is typical in GM1 gangliosidosis or other lysosomal storage disorders?

Answer 51

Bilateral thalamic T2 hyperintensity ± basal ganglia involvement.

Question 52

A teenager presents with neuropathic pain and MRI shows pulvinar hyperintensity. What condition should be suspected?

Answer 52

Fabry disease (X-linked lysosomal storage disorder).

Question 53

Which thalamic nuclei are vulnerable in Wilson disease and what MRI findings appear?

Answer 53

Mediodorsal and pulvinar nuclei; T2 hyperintensity ± 'face of the giant panda' sign in midbrain.

Question 54

What seizure type is associated with thalamocortical circuits in children?

Answer 54

Absence seizures (involving abnormal thalamocortical oscillations).

Question 55

A toddler with startle myoclonus, spasticity, and bilateral thalamic calcification should be evaluated for which condition?

Answer 55

Aicardi-Goutières syndrome or congenital TORCH infection.

Question 56

Which imaging modality is most sensitive for detecting early thalamic injury in neonates?

Answer 56

Diffusion-weighted MRI (DWI).

Question 57

A neonate with diffuse hypotonia and EEG burst-suppression pattern shows thalamic T2 hyperintensity. What condition is suspected?

Answer 57

Early infantile epileptic encephalopathy (Ohtahara syndrome).

Question 58

In what metabolic condition might the thalamus be spared while basal ganglia are involved?

Answer 58

Methylmalonic acidemia or propionic acidemia.

Question 59

What syndrome shows both thalamic and cerebellar involvement, often with motor regression and spasticity in early childhood?

Answer 59

Krabbe disease.

Question 60

How does the thalamus contribute to pediatric consciousness and coma states?

Answer 60

Intralaminar nucleus dysfunction disrupts cortical arousal loops, contributing to coma or vegetative states.

Question 61

In pediatric autoimmune encephalitis, what thalamic finding may be present?

Answer 61

T2/FLAIR hyperintensity, especially in NMDA-R or LGI1-related cases.