Inference generation during text comprehension by adults with right hemisphere brain damage: activation failure...

Area of Science:

• Neuroscience
• Cognitive Psychology
• Linguistics

Background:

• Conflicting evidence exists regarding inference generation in adults with right hemisphere brain damage (RHD).
• Some research suggests RHD impairs the activation of lexical-semantic bases for inferences.
• Other studies indicate RHD patients activate multiple interpretations, sometimes inappropriately.

Purpose of the Study:

• To contrast the activation failure hypothesis with the multiple interpretation hypothesis in RHD text comprehension.
• To investigate the relationship between activating incompatible inferences and discourse comprehension in RHD.

Main Methods:

• Thirty-seven adults with RHD and 34 controls listened to narratives requiring bridging inferences (BIs).
• Lexical decision tasks using auditory phoneme strings assessed word activation after text sentences.
• Target words related to compatible (BI) and incompatible (AI) interpretations were used.

Main Results:

• Adults with RHD showed faster and more accurate lexical decisions for BI-related words in the final sentence position, supporting BI generation.
• Evidence for alternate interpretation (AI) generation was observed in accuracy but not response times.
• Increased activation of contextually incompatible interpretations was linked to diminished discourse comprehension in RHD.

Conclusions:

• Contrary to the activation failure hypothesis, adults with RHD can generate the necessary lexical-semantic foundations for bridging inferences.
• Results partially support the multiple activation view, with evidence of AI generation in RHD.
• The findings highlight that prolonged activation of inappropriate interpretations negatively impacts discourse comprehension in RHD.