Review paper on semantic ambiguity resolution published in ‘Language and Linguistics Compass’

mouse-ambiguous-word

Sylvia Vitello and Jenni Rodd have written a review paper entitled “Resolving Semantic Ambiguities in Sentences: Cognitive Processes and Brain Mechanisms”. This paper was recently published in ‘Language and Linguistics Compass’.

Abstract:

fMRI studies of how the brain processes sentences containing semantically ambiguous words have consistently implicated (i) the left inferior frontal gyrus (LIFG) and (ii) posterior regions of the left temporal lobe in processing high-ambiguity sentences. Despite the consistency of these findings there is little consensus about the precise functional contributions of these regions. This article reviews recent findings on this topic and relates them to (i) psycholinguistic theories about the underlying cognitive processes and (ii) general neuro-cognitive accounts of the relevant brain regions. We suggest that the LIFG plays a general role in the cognitive control process that are necessary to select contextually relevant meanings and to reinterpret sentences that were initially misunderstood, but it is currently unclear whether these control processes should best be characterised in terms of specific processes such as conflict resolution and controlled retrieval which are only required for high-ambiguity sentences (and not for low-ambiguity sentences), or whether its function is better characterised in terms of a more general set of ‘unification’ processes that are essential for comprehending all sentences. In contrast to the relatively rapid progress that has been made in understanding the function of the LIFG, we suggest that the contribution of the posterior temporal lobe is less well understood and future work is needed to clarify its role in speech sentence comprehension.

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PhD Posters at the UCL PPG Cumberland Lodge Conference

Three PhD students in the Word Lab will be presenting posters of their research at the UCL PPG Cumberland Lodge Conference which will take place 27th-28th April. Links to these posters can be found below:

Update:

Following the Cumberland Lodge conference this week, we are pleased to announce that Eva was named the runner up in the poster competition. Congratulations, Eva!

New paper in Brain and Language

Localising semantic and syntactic processing in spoken and written language comprehension: An Activation Likelihood Estimation meta-analysis

Jennifer Rodd, Sylvia Vitello, Anna Woollams and Patti Adank

Abstract

We conducted an Activation Likelihood Estimation (ALE) meta-analysis to identify brain regions that are recruited by linguistic stimuli requiring relatively demanding semantic or syntactic processing. We included 54 functional MRI studies that explicitly varied the semantic or syntactic processing load, while holding constant demands on earlier stages of processing. We included studies that introduced a syntactic/semantic ambiguity or anomaly, used a priming manipulation that specifically reduced the load on semantic/syntactic processing, or varied the level of syntactic complexity. The results confirmed the critical role of the posterior left Inferior Frontal Gyrus (LIFG) in semantic and syntactic processing. These results challenge models of sentence comprehension highlighting the role of anterior LIFG for semantic processing. In addition, the results emphasise the posterior (but not anterior) temporal lobe for both semantic and syntactic processing.

Keywords

Syntax; Semantics; Neuroimaging; Meta-analysis; Methodology; fMRI

New paper in Frontiers in Human Neuroscience

Roles of frontal and temporal regions in reinterpreting semantically ambiguous sentences

Sylvia Vitello, Jane Warren, Joseph Devlin and Jennifer Rodd

Link to Article

Semantic ambiguity resolution is an essential and frequent part of speech comprehension because many words map onto multiple meanings (e.g., “bark,” “bank”). Neuroimaging research highlights the importance of the left inferior frontal gyrus (LIFG) and the left posterior temporal cortex in this process but the roles they serve in ambiguity resolution are uncertain. One possibility is that both regions are engaged in the processes of semantic reinterpretation that follows incorrect interpretation of an ambiguous word. Here we used fMRI to investigate this hypothesis. 20 native British English monolinguals were scanned whilst listening to sentences that contained an ambiguous word. To induce semantic reinterpretation, the disambiguating information was presented after the ambiguous word and delayed until the end of the sentence (e.g., “the teacher explained that the BARK was going to be very damp”). These sentences were compared to well-matched unambiguous sentences. Supporting the reinterpretation hypothesis, these ambiguous sentences produced more activation in both the LIFG and the left posterior inferior temporal cortex. Importantly, all but one subject showed ambiguity-related peaks within both regions, demonstrating that the group-level results were driven by high inter-subject consistency. Further support came from the finding that activation in both regions was modulated by meaning dominance. Specifically, sentences containing biased ambiguous words, which have one more dominant meaning, produced greater activation than those with balanced ambiguous words, which have two equally frequent meanings. Because the context always supported the less frequent meaning, the biased words require reinterpretation more often than balanced words. This is the first evidence of dominance effects in the spoken modality and provides strong support that frontal and temporal regions support the updating of semantic representations during speech comprehension.

Annual Meeting of the Experimental Psychology Society: 9-10 January 2014, University College London

Jenni Rodd  was the local organiser for this meeting of the Experimental Psychology Society: 9-10 January 2014, University College London, and organised a symposium on “The Cognitive Neuroscience of Sentence Comprehension”.

The lab contributed to four talks and a poster at this meeting:

1) Sylvia Vitello, Joseph Devlin and Jennifer Rodd: Time course of resolving ambiguous speech when disambiguating information is delayed.

2) Patti Adank: The neural locus of semantic and syntactic processing: a meta-analysis.

3) Jane Warren: Resolving semantic ambiguity during sentence comprehension: the role of inferior frontal cortex.

4) Eva Denise Poort* and Jennifer Rodd: Cross-language long-term word-meaning priming of cognates and interlingual homographs.

All abstracts available HERE

Society of the Neurobiology of Language: 2013 Annual Meeting in San Diego

The lab has contributed two posters and a talk to this meeting:

(1) The roles of left and right inferior frontal cortex in the comprehension of ambiguous sentences

Jennifer M. Rodd, Sylvia Vitello, Joseph T. Devlin, Jane E. Warren

Poster available HERE

Abstract HERE

 

(2) Neural responses to semantic ambiguities encountered during spoken sentences

Sylvia Vitello, Jane E. Warren, Joseph T. Devlin, Jennifer M. Rodd

Abstract HERE

 

(3) A meta-analysis of semantic and syntactic processing in language comprehension

Patti Adank, Sylvia Vitello, Anna Woollams, Jennifer Rodd

Abstract HERE