3 ms·
This recent publication about evidence for a proposed model for basic grammatical processing in the neocortex, was also fascinating: http://www.pnas.org/content
by sawwit 11y ago
This recent publication about evidence for a proposed model for basic grammatical processing in the neocortex, was also fascinating: http://www.pnas.org/content/112/37/11732.long http://www.pnas.org/content/112/37/11732.long
An architecture for encoding sentence meaning in left mid-superior temporal cortex
Human brains flexibly combine the meanings of words to compose
structured thoughts. For example, by combining the meanings of
“bite,” “dog,” and “man,” we can think about a dog biting a man,
or a man biting a dog. Here, in two functional magnetic resonance
imaging (fMRI) experiments using multivoxel pattern
analysis (MVPA), we identify a region of left mid-superior
temporal cortex (lmSTC) that flexibly encodes “who did what to
whom” in visually presented sentences. We find that lmSTC
represents the current values of abstract semantic
variables (“Who did it?” and “To whom was it done?”) in distinct
subregions. Experiment 1 first identifies a broad region of lmSTC
whose activity patterns (i) facilitate decoding of
structure-dependent sentence meaning (“Who did what to whom?”)
and (ii) predict affect-related amygdala responses that depend on
this information (e.g., “the baby kicked the grandfather”
vs. “the grandfather kicked the baby”). Experiment 2 then
identifies distinct, but neighboring, subregions of lmSTC whose
activity patterns carry information about the identity of the
current “agent” (“Who did it?”) and the current “patient” (“To
whom was it done?”). These neighboring subregions lie along the
upper bank of the superior temporal sulcus and the lateral bank
of the superior temporal gyrus, respectively. At a high level,
these regions may function like topographically defined data
registers, encoding the fluctuating values of abstract semantic
variables. This functional architecture, which in key respects
resembles that of a classical computer, may play a critical role
in enabling humans to flexibly generate complex thoughts.