Neuro Cerebellum MCQ's

Dysdiadokinesia refers to the inability to perform rapid alternating movements with the hands. This condition is characterized by difficulty in coordinating and executing movements that require rapid and alternating actions, such as rapidly pronating and supinating the hands. It is often seen in neurological disorders such as cerebellar dysfunction or damage.

The patient's ataxia and swaying, which persist even when his eyes are open, suggest a problem with the cerebellum. The cerebellum is responsible for coordinating movement and maintaining balance. Damage to the cerebellum can result in unsteady and uncoordinated movements, leading to ataxia. The normal vibration sense on all four limbs indicates that the dorsal columns, which transmit sensory information such as vibration sense, are intact. The cerebral peduncles, posterior limb of the internal capsule, and ventral horns of the spinal cord are not directly involved in coordinating movement and balance, making them less likely to be the cause of the patient's symptoms.

The correct answer is Fastigial nucleus. The flocculo-nodular lobe circuitry of the cerebellum is primarily involved in coordinating eye movements and balance. The Fastigial nucleus is responsible for receiving input from the flocculo-nodular lobe and sending output to the vestibular nuclei, which are important for balance control. Therefore, lesioning the Fastigial nucleus would specifically target the circuitry related to the flocculo-nodular lobe.

The patient's symptoms of an unsteady "drunk like" gait and swaying suggest that the cerebellar hemorrhage affected the flocculonodular lobe. The flocculonodular lobe is responsible for coordinating balance and posture, and damage to this region can result in ataxia and unsteady movements.

Purkinje cells are the major output neurons of the cerebellar cortex. They receive inputs from various sources within the cerebellum and send their axons to different targets outside the cerebellum. These cells play a crucial role in motor coordination and learning. They are characterized by their distinctive morphology, with a large, flat dendritic tree that receives inputs from parallel fibers and a single axon that projects to the deep cerebellar nuclei. Purkinje cells are critical for the integration and modulation of motor signals, making them the major output neurons of the cerebellar cortex.

The patient's symptoms of slurred speech and dysmetria on the left side indicate a lesion in the left cerebellar hemisphere. The cerebellum is responsible for coordinating voluntary movements, including speech and limb movements. Lesions in the cerebellar hemisphere can result in ipsilateral (same side) symptoms, such as the ones seen in this patient. The other options, such as the cerebellar vermis, right cerebellar hemisphere, fastigial nucleus, and vestibular nuclei, are not consistent with the patient's symptoms.

Granule cell parallel fibers and mossy fibers both provide excitatory input.

Efferent axons from the dentate nucleus terminate in the ventral lateral nucleus of the thalamus (VL) and travel through the superior cerebellar peduncle.

The correct answer is the Anterior spinocerebellar tract. This ascending pathway enters the cerebellum through the peduncle marked in the picture. The other options listed are not associated with this specific peduncle.