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21. Anatomy of the basal ganglia (I)

  1. Dorsal striatum = Putamen + Caudate nucleus?
  2. Dorsal striatum = Putamen + Globus pallidus
  3. Lentiform nucleus = Putamen + Globus pallidus ?
  4. Ventral striatum = Nucleus accumbens + Olfactory tubercle
  5. Ventral striatum = Nucleus accumbens + Claustrum
  6. Ventral pallidum = GPi + GPe?

  1. T
  2. F
  3. T
  4. T
  5. F
  6. F

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20. Brown-Séquard syndrome

  1. Sensation of pain is lost contralateraly to the lesion, beginning one or two segments below the lesion?
  2. Proprioception is lost ipsilateraly to the lesion, beginning one or to segments below the lesion?
  3. Flaccid paralysis is present ipsilateraly to the lesion and below the level of the lesion?
  4. Spastic paralysis  is present contralateraly to the lesion,  at the level of the lesion?
  5. Sensation of vibration is lost ipsilateraly to the lesion?
  6. Sensation of temperature is lost on the both sides, one to two segments below the level of the lesion?

  1. T
  2. F
  3. F
  4. F
  5. T
  6. F

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19. Cranial nerve nuclei – location

  1. Trochlear nucleus: Mesencephalon?
  2. Dorsal cochlear nucleus: Pons?
  3. Ventral cochlear nucleus: Medulla?
  4. Oculomotor nucleus: Mesencephalon?
  5. Facial nucleus: Pons?
  6. Edinger-Westphal nucleus: Pons?

  1. T
  2. T
  3. F
  4. T
  5. T
  6. F

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18. Abducens nerve

  1. Innervates only one single muscle of the eye, the lateral rectus muscle?
  2. Axons from the abducens nerve loop around the facial motor nucleus, creating the facial colliculus that is visible on the floor of the fourth ventricle?
  3. Besides the motor neurons, which directly innervate ipsilateral lateral rectus muscle via the abducens nerve, abducens nucleus contains also interneurons, which project to the contralateral oculomotor nucleus and cause conjugate movement (adduction) of the contralateral eye?
  4. Besides the motor neurons, which directly innervate ipsilateral medial rectus muscle via the oculomotor nerve, oculomotor nerve nucleus contains also interneurons, which project to the contralateral abducens nucleus and cause conjugate movement (abduction) of the contralateral eye?
  5. A lesion to the nucleus of the abducens nerve causes inability to move the eyes together in the direction of the side with the lesion?
  6. In peripheral abducens palsy, the contralateral eye is slightly adducted because of the unopposed tonic action of the medial rectus muscle?

  1. T
  2. F
  3. T
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  5. T
  6. F

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17. Ataxia

  1. Widespread cerebellar lesions cause more or less symmetrical symptomatology, while localized, unilateral cerebellar lesions cause contralateral hemiataxia. (T/F?)
  2. Worsening of symptoms of ataxia when the eyes are shut indicates absence of sensory ataxia. (T/F?)
  3. Romberg’s test is negative in sensory ataxia. (T/F?)
  4. Scanning speech is typically associated with sensory ataxia. (T/F?)
  5. In tandem Romberg’s test patient places his or her feet in heel-to-toe position with one foot  in front of the other. (T/F?)
  6. Intention tremor is associated with cerebellar ataxia. (T/F?)

  1. F
  2. F
  3. F
  4. F
  5. T
  6. T

  1. Unilateral cerebellar lesions cause ipsilateral hemiataxia.
  2. Sensory ataxia is caused by loss of proprioception, and is worsened when proprioception cannot be compensated by visual input.
  3. Romberg’s test is positive in sensory ataxia.
  4. Scanning speech is a symptom of a lesion in the cerebellum.

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16. GABAergic cells of the cerebellum

  1. Purkinje cells, one of the largest neurons in the brain, exert inhibitory effects on their targets and use GABA as their neurotransmitter?
  2.  Cerebellar Golgi cells are located in the granular layer of the cerebellum and they use GABA as their neurotransmitter?
  3. Cerebellar stellate cells are inhibitory interneurons located in the  molecular layer of the cerebellum and they use GABA as their neurotransmitter?
  4. Unipolar brush cells (UBCs) are a class of inhibitory  interneurons found in the granular layer of the cerebellar cortex which use GABA as their neurotransmitter?
  5. Cerebellar basket cells synapse on the cell bodies of Purkinje cells, exert inhibitory effect on them, and use GABA as their neurotransmitter?
  6. Cerebellar granule cells are the most numerous neurons in the brain, they use glutamate as their neurotransmitter  and  exert excitatory effects on their targets?

  1. T
  2. T
  3. T
  4. F
  5. T
  6. T

  1. Unipolar brush cells (UBCs) are excitatory glutamatergic interneurons. They can be found the granular layer of the cerebellar cortex but also in the cochlear nucleus in the brainstem.

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15. The deep cerebellar nuclei

  1. Receive glutamatergic inputs from Purkinje’s cells. (T/F?)
  2. Most of the output fibers of the cerebellum originate from the deep cerebellar nuclei, with the exception of the fibers from the flocculonodular lobe, witch synapse directly with the inferior olivary nucleus (ION). (T/F?)
  3. The dentate nuclei are situated deep within the lateral hemispheres of the cerebellum and receive most of their connections from the lateral hemispheres  of the cerebellum. (T/F?)
  4. The dentate nucleus can be divided into dorsal (motor) and ventral (nonmotor) domains. (T/F?)
  5. The interposed nucleus is composed of globose nucleus and emboliform nucleus and is located in the vermis. (T/F?)
  6. Fastigial nuclei are paired structures located in vermis. (T/F?)

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  2. F
  3. T
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  6. T

  1. The deep cerebellar nuclei receive GABAergic (inhibitory) inputs from Purkinje’s cells.
  2. The fibers from the flocculonodular lobe synapse directly with the vestibular nuclei.
  1. The interposed nucleus is located in the paravermal (intermediate) zone.

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14. Anatomy of the cerebellum

  1. It has about 10% of the total brain volume. (T/F?)
  2. It has about 3.6 times less neurons than there is in the neocortex. (T/F?)
  3. Two cerebellar peduncles connect cerebellum with the rest of the brain. (T/F?)
  4. The cerebrocerebellum, or neocerebellum receives input exclusively from the cerebral cortex via the pontine nuclei. (T/F?)
  5. Two of the deep cerebellar nuclei, the dentate and the emboliform are fused and form a single, interposed nucleus. (T/F?)
  6. All output fibers from the cerebellum originate from the deep cerebellar nuclei. (T/F?)

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  4. T
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  6. F

  1. The cerebellum contains more neurons than the total from the rest of the brain, first of all because of the large number of the granule cells.
  2. There are three cerebellar peduncles that connect cerebellum with the rest of the brain, the superior cerebellar peduncle, the middle cerebellar peduncle and the inferior cerebellar peduncle.
  1. The globose and the emboliform nucleus form interposed nucleus.
  2. Most of the output fibers from the cerebellum originate from the deep cerebellar nuclei. The exception is the flocculonodular lobe, its output goes to the vestibular nuclei.

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13. Afferents to the cerebellum:

  1. The anterior spinocerebellar tract  carries proprioceptive information from muscle spindles and Golgi tendon organs of ipsilateral part of trunk and lower limb and enters the cerebellum through the inferior cerebellar peduncle. (T/F?)
  2. The anterior spinocerebellar tract crosses to the opposite side of the body first in the spinal cord as part of the anterior white commissure and then crosses again and enters the cerebellum via the inferior cerebellar peduncle. (T/F?)
  3. The cuneocerebellar tract enters the cerebellum via the inferior cerebellar peduncle on the opposite side. (T/F?)
  4. Tectocerebellar fibers enter the cerebellum via the middle peduncle from the ipsilateral midbrain colliculi. (T/F?)
  5. The pontocerebellar tract from the  ipsilateral  brainstem enters through the middle peduncle. (T/F?)
  6. Trigeminocerebellar fibers enter through the middle peduncle. (T/F?)

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  1. The anterior or ventral spinocerebellar tract enters the cerebellum through the superior cerebellar peduncle. It crosses side first in the spinal cord as part of the anterior white commissure and then it crosses it again in the cerebellum, so it does carry proprioceptive information from the ipsilateral side of the body.
  2. Yes, it double-crosses side like it is explained but does not enter cerebellum through the inferior cerebellar peduncle
  3. The cuneocerebellar tract enters the cerebellum via the inferior cerebellar peduncle on the same side.
  4. Tectocerebellar fibers enter the cerebellum via the superior peduncle and they origin from the superior and inferior colliculi on both sides.
  5. The pontocerebellar tract from the contralateral  brainstem enters through the middle peduncle.
  6. Trigeminocerebellar fibers enter through the inferior cerebellar peduncle.

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12. MRI in a few (too) easy steps:

  1. Hydrogen protons have a constant spin, with random orientation of spinning axes at rest. (T/F?)
  2. In a strong static magnetic field, all the axes the spinning electrons orient along magnet’s longitudinal axes. (T/F?)
  3. An excitatory infrared-frequency pulse at right angles to the axis of the magnetic field knocks hydrogen protons out of alignment with the magnetic field and forces them into phase with other hydrogen protons. (T/F?)
  4. The nuclei go out of phase after switching off the radio frequency (T1 time). (T/F?)
  5. T2 is a measure of the time taken for spinning protons to realign with the external magnetic field. (T/F?)
  6. As protons move back into alignment with the magnetic field, and fall out of “phase” with each other, they emit RF energy. (T/F?)

  1. T
  2. T
  3. F
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  6. T

  1. An excitatory radiofrequency (RF) pulse at right angles to the axis of the magnetic field knocks hydrogen protons out of alignment with the magnetic field and forces them into phase with other hydrogen protons.
  2. Time needed for hydrogen nuclei to go out of faze after switching off the radiofrequency field is called T2.
  3. The T1 relaxation time (spin lattice relaxation time or longitudinal relaxation time) is a measure of the time that is needed for spinning protons to realign with the external magnetic field.