Semantic dementia patients and the face-sorting task
Chapter 3 endnote 10, from Lisa Feldman Barrett.
Some context is:
The patients [with semantic dementia] then sorted the photos into piles in any way that was meaningful to them. They were unable to group all scowling faces into an anger pile, all pouting faces into a sadness pile, and so on.
In addition to the unstructured sorting task described above, we asked the patients to sort the photos into exactly six piles, instead of leaving the number unspecified. We offered the patients six emotion words to direct their sorting. Their emotion perception did not improve.
Other studies have looked at non-human primates, such as chimpanzees and rhesus macaques. These primates were able to distinguish negative faces (e.g., bared teeth) from neutral faces in their own species, but, like our semantic dementia patients, had great difficulty distinguishing one negative face from another (e.g., bared teeth vs. screaming). This evidence could mean that these primates, like semantic dementia patients, can distinguish valence, not emotion, in one another’s faces.
Notes on the Notes
- Lindquist, Kristen A., Maria Gendron, Lisa Feldman Barrett, and Bradford C. Dickerson. 2014. "Emotion perception, but not affect perception, is impaired with semantic memory loss." Emotion 14 (2): 375-387.
- For an overview, see Bliss-Moreau, Eliza. & G. Moadab. 2017. "The faces monkeys make." In The Science of Facial Expression, edited by Jose-Miguel Fernandez Dols & James A. Russell. New York: Oxford University Press.