From the Research
To test for the grasp reflex in adults, stroke the patient's palm with your fingers while their hand is relaxed and open, as this is the most effective method to elicit a response 1. A positive grasp reflex occurs when the patient involuntarily closes their hand and grasps your fingers. This primitive reflex is normally absent in healthy adults but may reappear with certain frontal lobe pathologies. When performing the test, ensure the patient is comfortable and their arm is supported. Approach from the ulnar side of the hand (pinky finger side) and stroke across the palm toward the thumb. The test should be performed bilaterally to compare responses. A positive grasp reflex in adults is pathological and suggests frontal lobe dysfunction, which may occur in conditions such as dementia, stroke, or traumatic brain injury, as noted in studies such as 2 and 3. The grasp reflex is considered a "frontal release sign" because it indicates damage to the frontal lobe areas that normally inhibit this primitive reflex. If you detect a positive grasp reflex, further neurological evaluation is warranted to determine the underlying cause, considering the potential impact on the patient's quality of life and morbidity, as discussed in 1. Some key points to consider when testing for the grasp reflex include:
- The patient's hand should be relaxed and open
- The test should be performed bilaterally
- A positive response is indicative of frontal lobe dysfunction
- Further evaluation is necessary to determine the underlying cause of a positive grasp reflex, taking into account the patient's overall health and potential for morbidity and mortality, as well as the impact on their quality of life.