Henry Gustav Molaison had to undergo brain surgery for which of the following reasons, leading to our current day understanding of how we process memories?
Group of answer choices
He had encephalitis as a child.
He was part of a medical trial study.
He had severe seizures.
He was born with an extra area of cortex.
The Correct Answer and Explanation is:
Correct Answer: He had severe seizures.
Explanation
Henry Gustav Molaison, often referred to in scientific literature as H.M., became one of the most important patients in the history of neuroscience due to a brain surgery he underwent in 1953 to alleviate his severe and debilitating seizures. From a young age, Henry suffered from epilepsy, likely caused by a bicycle accident when he was a child, which resulted in head trauma. His seizures grew progressively worse over time, becoming so severe that they severely impacted his daily functioning and quality of life.
At the age of 27, desperate for relief, Henry underwent an experimental surgical procedure performed by neurosurgeon Dr. William Scoville. The surgery involved the removal of parts of his medial temporal lobe, including most of the hippocampus on both sides of his brain. While the procedure was successful in significantly reducing the frequency and severity of his seizures, it also resulted in a profound and unexpected side effect—Henry was no longer able to form new long-term memories, a condition known as anterograde amnesia.
Despite being able to remember events from his childhood and maintain short-term memory for a brief period, he could not store new experiences into long-term memory. This made Henry’s case critical for scientists studying memory. Research conducted over the decades following his surgery, particularly by neuroscientist Brenda Milner, demonstrated that the hippocampus plays a crucial role in the formation of new declarative memories (memories of facts and events).
Henry’s case profoundly shaped our modern understanding of how memory works. It showed that memory is not a single, unified process but consists of different systems in the brain. His experience helped establish the foundation for cognitive neuroscience and remains a key reference in the study of memory, brain function, and neuropsychology.
