Neural Systems Involved When Attending to a Speaker

Abstract

Remembering what a speaker said depends on attention. During conversational speech, the emphasis is on working memory, but listening to a lecture encourages episodic memory encoding. With simultaneous interference from background speech, the need for auditory vigilance increases. We recreated these context-dependent demands on auditory attention in 2 ways. The first was to require participants to attend to one speaker in either the absence or presence of a distracting background speaker. The second was to alter the task demand, requiring either an immediate or delayed recall of the content of the attended speech. Across 2 fMRI studies, common activated regions associated with segregating attended from unattended speech were the right anterior insula and adjacent frontal operculum (aI/FOp), the left planum temporale, and the precuneus. In contrast, activity in a ventral right frontoparietal system was dependent on both the task demand and the presence of a competing speaker. Additional multivariate analyses identified other domain-general frontoparietal systems, where activity increased during attentive listening but was modulated little by the need for speech stream segregation in the presence of 2 speakers. These results make predictions about impairments in attentive listening in different communicative contexts following focal or diffuse brain pathology.

Comprehending auditory speech: previous and potential contributions of functional MRI

“…These components are extracted in a data driven manner, with the timecourse of each component regressed against the experimental design to establish the component's task relatedness (Calhoun, Adali, Pearlson, & Pekar, 2001; see examples from Braga, Wilson, Sharp, Wise, & Leech, 2013;Kamourieh et al, 2015). Whilst ICA is unable to assess causal relations in the functional connectivity between regions, it does have the advantage that it can be conducted on the whole brain without prior assumptions about the underlying structure of functional networks.…”

“…This may be a useful approach for studying effortful listening, which has previously been shown to engage both domain-general attentional and domain-specific sensory systems (Binder et al, 2004;Evans et al, 2016;Vaden et al, 2013;Wild et al, 2012). Furthermore, the ability to de-mix neural signals into functionally independent networks may be of particular benefit in complex experimental designs in which multiple events occur simultaneously within a trial, for example in "cocktail party listening" or speaking in noise (Braga et al, 2013;Evans et al, 2016;Kamourieh et al, 2015;Meekings et al, 2016). Finally, an additional advantage of ICA is that components from a particular study can be compared to those extracted from large scale studies of resting state networks by correlating the spatial maps (Smith et al, 2009).…”

Brain correlates of the orientation of auditory spatial attention onto speaker location in a “cocktail‐party” situation

“…This possibility seems plausible as well. Several neuroimaging studies have observed FEF activity with tasks of auditory spatial attention (Kamourieh et al, 2015;Mayer, Harrington, Adair, & Lee, 2006;Salmi, Rinne, Koistinen, Salonen, & Alho, 2009;Wu, Weissman, Roberts, & Woldorff, 2007). Using magnetoencephalography (MEG) and stimulation with two simultaneous virtual sound sources, Lee et al (2013) found enhanced activity in left FEF prior to and throughout the auditory stimulus when subjects directed auditory attention to target location compared to when they focused on target pitch.…”

“…Both these streams might converge in frontal cortex (Zündorf, Lewald, & Karnath, ). With cocktail‐party tasks, specific networks have been revealed, namely, posterior superior temporal gyrus (STG), including planum temporale, IPL, inferior frontal and dorsofrontal cortices, as well as pre‐ and postcentral areas (e.g., Bharadwaj, Lee, & Shinn‐Cunningham, ; Kamourieh et al, ; Lee et al, ; Lewald & Getzmann, ; Zündorf, Karnath, & Lewald, ; Zündorf, Lewald, & Karnath, ).…”

Music Perception in Dementia

“…Such an analysis is fundamental to the initial parsing of a musical 'scene', before more detailed analysis can occur [7]; it is likely to entail an interaction of bottom-up mechanisms for coding perceptual structure with top-down mechanisms for resolving perceptual ambiguities based on stored templates or schemas derived from past experience of music [5,67]. Musical scene analysis has not been widely studied neuropsychologically in clinical populations but is likely to engage posterior superior temporal and parietal lobe regions and their dorsal projections [68][69][70][71][72]. AD has been shown to produce a generic impairment of auditory scene analysis under diverse listening tasks and conditions, including the streaming of sound sequences that bear some similarities to musical melodies; this has been linked to dysfunction of posterior temporoparietal areas overlapping those involved in music perception [33,35,36,[73][74][75].…”