Before You Begin
Question #47465
The Question
A patient exhibits severe incoordination, intention tremors, and an unsteady gait leaning towards the right side, but shows absolutely no loss of muscle strength or paralysis. Based on the principles of neural processing and motor control, identify the most likely site of the lesion and its corresponding functional disruption.
Options
- A.
Right primary motor cortex; failure to initiate contralateral voluntary movements.
- B.
Left cerebellar hemisphere; disruption of the contralateral feedback loop for motor execution.
- C.
Right cerebellar hemisphere; failure to integrate ipsilateral sensory feedback with intended motor commands.
- D.
Left primary motor cortex; disruption of pyramidal tracts leading to ipsilateral ataxia.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Regulatory_Failure
Understand how NOT, EXCEPT, and logical constraints are used to manipulate exam results.
Concepts Behind This Question
Cerebellum|Pyramidal_Tracts|Purkinje_Cells
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students frequently generalize the 'contralateral control' rule of the cerebrum to the entire brain.
The trap lies in failing to recognize that cerebellar coordination operates via an ipsilateral feedback loop.
Additionally, students must distinguish between the loss of motor initiation (paralysis - motor cortex) and the loss of motor fine-tuning (ataxia - cerebellum).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Neural Control and Coordination - Class 11 |
| Concept | Ipsilateral vs Contralateral Signaling |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |