Lang: Robertson: Funct Neuroanatomy Cogn Proc Mapping Discourse Compre

Front 1

How did brain activity in the left hemisphere differ for non-letter strings v. sentences?

Back 1

Non-letter strings: left hemisphere activated, extending from the angular gyrus rostrally to the left anterior temporal pole along the middle gyrus. Small region of activation also noted in right hemisphere. These activations are suggestive of a language processing circuit localized in the left hemisphere.

Sentences: frontal lobe activated. For def. articles, most prominent activation clusters were around the right hemisphere of the frontal lobe, and for indefinite articles, activation clusters were primarily around the left hemisphere.

Front 2

What area (hemisphere and lobe) of the brain showed the most activity for sentences with definite articles.

Back 2

Most prominent activation clusters were around the right hemisphere of the frontal lobe

Front 3

hypothesis

Back 3

These authors suggest that the definite article "the" serves as the basis for cognitive process mapping by providing a cue to discourse coherence.

Front 4

participants

Back 4

8 right handed neurologically normal participants.

Front 5

procedure

Back 5

(1) Each participant read a series of sentences, some of which are composed of indefinite artices, and some composed of deninite articles.
(2) Participants also asked to alternate btwn reading series of sentences and viewing series of non-letter character strings (e.g., @#*&^%).
(3) Sentences were presented in blocks. Each block had 11 sentences. Each participant was presented with all possible blocks.
(4) fMRI was used to identify regions of neural activity associated with comprehending connected discourse vs. comprehending unconnected discourse.
(5) After each block (level) was completed, participants did a recognitiion test, judging whether test sentences were old or new.

Front 6

results

Back 6

For non-letter strings: left hemisphere activated, extending from the angular gyrus rostrally to the left anterior temporal pole along the middle gyrus. Small region of activation also noted in right hemisphere.

For Sentences: frontal lobe activated.

For def. articles, most prominent activation clusters were around the right hemisphere of the frontal lobe, and for indefinite articles, activation clusters were primarily around the left hemisphere

Front 7

take away

Back 7

• Non-letter string activation patterns are suggestive of a language processing circuit localized in the left hemisphere.

• cognitive mapping is accompanied by more neural activity in the right hemisphere, which challenges conventional beliefs about language lateralization occurring in the left hemisphere.

• altering a single word in the language input can result in qualitatively different activity in the brain-provided the single word carries an important cue for comprehension processes.

•Shive says: A big criticism of this research is that it’s just showing where things happen as opposed to how things happen (it's correlational). However, these researchers emphasize that in order to think about how things happen, we need to first understand where things are happening.