FAU Advanced Health Assessment Practice Test

What suggests a lesion within or near the cerebral hemispheres?

1. Decerebrate rigidity

2. Flexor response

3. Cerebellar ataxia

4. Extensor response

The correct answer is: Flexor response

The flexor response indicates higher-level brain activity, typically associated with the cerebral hemispheres, particularly in the context of motor response to stimuli. When assessing a patient’s motor responses, a flexor response, also known as a withdrawal response, occurs when a painful stimulus prompts the individual to pull away, which is mediated by pathways within the cerebral hemispheres, reflecting the presence of intact brain function in this region. In contrast, other responses such as decerebrate rigidity and extensor responses can indicate more severe impairment or dysfunction localized lower in the brain, such as in the midbrain or at the brainstem level. Cerebellar ataxia, on the other hand, pertains to coordination issues arising from the cerebellum and indicates that the problem is not primarily in the cerebral hemispheres. Thus, the flexor response is the most indicative of a lesion within or near the cerebral hemispheres due to its association with higher cortical function and voluntary control.