What is the purpose of Wada testing in presurgical planning?

• A. To determine language and memory representation of each hemisphere so surgery avoids essential cognitive functions.
• B. To assess overall IQ pre-surgery.
• C. To measure global cognitive decline.
• D. To identify motor deficits.

Answer: (A)

Wada testing is used to map where language and memory functions are represented in each hemisphere so the surgeon can plan an operation that avoids damaging essential cognitive abilities. The test briefly anesthetizes one hemisphere at a time, then assesses language tasks and memory encoding while the other side stays awake. This reveals which hemisphere controls language and where memory processes are localized, informing decisions about which tissue can be safely resected and how to minimize postoperative language or memory deficits. It’s especially important for epilepsy surgery involving the temporal lobe, where the risk to verbal memory is a major concern. Other assessments like IQ, global cognitive decline, or motor function don’t provide this precise mapping of language and memory essential for presurgical risk assessment.