Patient SM

Overview

Patient SM is the amygdala-lesion research case used in the Huberman Lab emotion episode to separate fear perception, external-threat fear, and internal panic.

Current Profile

In the source, Ralph Adolphs presents SM as a central caution against calling the amygdala a single fear center. Bilateral amygdala lesions are associated with difficulty perceiving fear in facial expressions and little reported conscious fear in some external-threat contexts, yet carbon-dioxide inhalation can still produce panic. The case therefore supports Amygdala Fear Dissociation rather than a simple absence-of-fear story.

Key Characteristics

• SM is described as having bilateral amygdala lesions.
• The case is linked to difficulty perceiving fear in facial expressions.
• The episode reports little conscious fear in some external-threat settings.
• CO2-induced panic is used to show that internal suffocation signals can rely on different circuits.
• The case qualifies, rather than erases, the amygdala’s importance for fear.

Evidence

• Facial fear perception - Neuroscience of Emotions & Tools for Improving Emotion Regulation | Dr. Ralph Adolphs has Adolphs describe SM’s difficulty perceiving fear in facial expressions after bilateral amygdala lesions.
• External threat - Neuroscience of Emotions & Tools for Improving Emotion Regulation | Dr. Ralph Adolphs reports little apparent conscious fear in settings such as haunted houses, snakes, spiders, or horror movies.
• Internal panic - Neuroscience of Emotions & Tools for Improving Emotion Regulation | Dr. Ralph Adolphs says amygdala-lesion patients still had panic attacks after inhaling carbon dioxide.

Qualifications

The page is source-scoped to the episode summary. It does not independently reconstruct SM’s full clinical record or the broader lesion literature.

What Changed

• Added SM as the amygdala-lesion case anchoring the fear-dissociation concept.

Relationships

• Ralph Adolphs - researcher explaining the case in the episode.
• Amygdala Fear Dissociation - main concept supported by the case.
• Social Emotion Inference Limits - related facial-expression inference boundary.
• Brain-Body Emotion Mapping - related internal-body-signal branch.