Sensory-Biased and Multiple-Demand Processing in Human Lateral Frontal Cortex

Abstract

The functionality of much of human lateral frontal cortex (LFC) has been characterized as "multiple demand" (MD) as these regions appear to support a broad range of cognitive tasks. In contrast to this domain-general account, recent evidence indicates that portions of LFC are consistently selective for sensory modality. Michalka et al. (2015) reported two bilateral regions that are biased for visual attention, superior precentral sulcus (sPCS) and inferior precentral sulcus (iPCS), interleaved with two bilateral regions that are biased for auditory attention, transverse gyrus intersecting precentral sulcus (tgPCS) and caudal inferior frontal sulcus (cIFS). In the present study, we use fMRI to examine both the multiple-demand and sensory-bias hypotheses within caudal portions of human LFC (both men and women participated). Using visual and auditory 2-back tasks, we replicate the finding of two bilateral visual-biased and two bilateral auditory-biased LFC regions, corresponding to sPCS and iPCS and to tgPCS and cIFS, and demonstrate high within-subject reliability of these regions over time and across tasks. In addition, we assess MD responsiveness using BOLD signal recruitment and multi-task activation indices. In both, we find that the two visual-biased regions, sPCS and iPCS, exhibit stronger MD responsiveness than do the auditory-biased LFC regions, tgPCS and cIFS; however, neither reaches the degree of MD responsiveness exhibited by dorsal anterior cingulate/presupplemental motor area or by anterior insula. These results reconcile two competing views of LFC by demonstrating the coexistence of sensory specialization and MD functionality, especially in visual-biased LFC structures. Lateral frontal cortex (LFC) is known to play a number of critical roles in supporting human cognition; however, the functional organization of LFC remains controversial. The "multiple demand" (MD) hypothesis suggests that LFC regions provide domain-general support for cognition. Recent evidence challenges the MD view by demonstrating that a preference for sensory modality, vision or audition, defines four discrete LFC regions. Here, the sensory-biased LFC results are reproduced using a new task, and MD responsiveness of these regions is tested. The two visual-biased regions exhibit MD behavior, whereas the auditory-biased regions have no more than weak MD responses. These findings help to reconcile two competing views of LFC functional organization.

Domain-general and domain-specific computations in single word processing

“…The findings about increased bilateral frontotemporal activity in response to domain-general processing demands are consistent with the existing evidence from different languages (English, Polish, Italian) that this network supports core comprehension processes of mapping spoken words onto their representations, and is particularly engaged when this process becomes demanding (e.g., due to the presence of an embedded stem and competition between it and the full form, demands of morpho-phonological segmentation or top-down selection etc; Bozic et al, 2010;Carota et al, 2016). Engagement of the extended bilateral frontotemporal network in response to domain-general demands in language processing is also in line with the literature that associates parts of this network with the multiple demand system for cognitive control (Crittenden & Duncan, 2014), auditory attentional control (Noyce et al, 2017), inhibition and response monitoring (Henson et al, 1999). The link to domain-general processes is further reinforced by the observed cerebellum activation, which has been associated with executive functions needed for language processing (e.g., Bellebaum & Daum, 2007).…”

Hemodynamic responses link individual differences in informational masking to the vicinity of superior temporal gyrus

“…The current data confirm that cortical regions at or near STG and cIFS engage during masked speech comprehension tasks (Scott et al, 2004(Scott et al, , 2006(Scott et al, , 2009Rowland et al, 2018;Kerlin et al, 2010;Mesgarani and Chang, 2012;Ding and Simon, 2012;Michalka et al, 2015;Noyce et al, 2017).…”

Gradients of functional organization in posterior parietal cortex revealed by visual attention, visual short-term memory, and intrinsic functional connectivity

“…Study 1: Resting-state fMRI data were collected from 14 individuals (6 female). Visual vs. auditory working memory task fMRI results for these 14 subjects were previously reported ( Noyce et al, 2017 , 2018 ), and these findings were used to create regions of interest (ROIs) in lateral frontal cortex for the resting-state analysis described here. Study 2: Visual working memory change-detection (VWM-cd) task fMRI data were collected from 9 individuals (3 female).…”

“…Task-based fMRI studies reveal functional subdivisions with frontal and parietal cortex. Visual attention tasks have commonly elicited frontal lobe activation near the intersection of the superior frontal sulcus and the superior branch of the precentral sulcus (sPCS) and the intersection of the inferior frontal sulcus and the inferior branch of the precentral sulcus (iPCS) ( Hagler et al, 2006 ; Szczepanski et al, 2010 ; Michalka et al, 2015 ; Brissenden et al, 2016 ; Ester et al, 2016 ; Noyce et al, 2017 ). Visual tasks with stronger cognitive demands often produce more anterior cortical activity in the middle frontal gyrus and/or the midsection of inferior frontal sulcus (midIFS) ( Hagler et al, 2006 ; Badre, Keyser & D’Esposito, 2010 ; Barch et al, 2013 ).…”