Dynamics of the Multiple Demand Network Connectivity Under Varied Speech to Noise Ratios

Poster Session A - Saturday, April 13, 2024, 2:30 – 4:30 pm EDT, Sheraton Hall ABC

Madison Tutton¹ (mtutton2@uwo.ca), Ali Tafakkor¹, Björn Herrmann^3,4, Aysha Motala⁵, Ingrid Johnsrude^1,2; ¹Department of Psychology, Western University, ²School of Communication Sciences & Disorders, Western University, ³Rotman Research Institute at Baycrest Academy for Research and Education, ⁴Department of Psychology, University of Toronto, ⁵Department of Psychology, University of Stirling

Speech listening engages the domain-general Multiple Demand (MD) network, which does not appear to reflect operations required for speech understanding, but rather a general increase in effort. The MD network includes the cingulo-opercular network (CON) and the frontoparietal network (FPN). Within the CON, the anterior insula (AI) appears responsible for performance monitoring and salience signaling (Menon and Uddin, 2010; Shenhav et al., 2013) while the dorsal anterior cingulate cortex (dACC) appears involved in effort allocation. If listening conditions worsen, we hypothesize that the AI will increasingly signal the dACC, which coordinates with the FPN to implement cognitive control mechanisms (Kerns et al., 2006; Dosenbach et al., 2008). It is unclear if the MD regions covary together or separate into differentiable systems as listening to speech becomes effortful. The current study examines the impact of a varying signal-to-noise ratio (SNR) during story listening on the dynamics of the MD network. Healthy adults (N = 44, 19 – 34 years) listened to three stories, each approximately 10 to 13 minutes long, whilst undergoing functional MRI scanning. Each story contained a 12-talker babble masker and the SNR pseudo-randomly varied every 30 to 33 seconds across five SNRs: clear, +12, +7, +2, and – 3 dB. We will employ a generalized psychophysiological interaction (gPPI) analysis to investigate how functional connectivity is modulated by SNR between the implicated regions of the MD network. We expect that the functional connectivity within the CON, and between the CON and FPN, will increase as SNR declines.

Topic Area: ATTENTION: Auditory