title: Mental imagery of speech implicates two mechanisms of perceptual reactivation.
abstract: Sensory cortices can be activated without any external stimuli. Yet, it is still unclear how this perceptual reactivation occurs and which neural structures mediate this reconstruction process. In this study, we employed fMRI with mental imagery paradigms to investigate the neural networks involved in perceptual reactivation. Subjects performed two speech imagery tasks: articulation imagery (AI) and hearing imagery (HI). We found that AI induced greater activity in frontal-parietal sensorimotor systems, including sensorimotor cortex, subcentral (BA 43), middle frontal cortex (BA 46) and parietal operculum (PO), whereas HI showed stronger activation in regions that have been implicated in memory retrieval: middle frontal (BA 8), inferior parietal cortex and intraparietal sulcus. Moreover, posterior superior temporal sulcus (pSTS) and anterior superior temporal gyrus (aSTG) was activated more in AI compared with HI, suggesting that covert motor processes induced stronger perceptual reactivation in the auditory cortices. These results suggest that motor-to-perceptual transformation and memory retrieval act as two complementary mechanisms to internally reconstruct corresponding perceptual outcomes. These two mechanisms can serve as a neurocomputational foundation for predicting perceptual changes, either via a previously learned relationship between actions and their perceptual consequences or via stored perceptual experiences of stimulus and episodic or contextual regularity.
authors.affiliation: New York University Shanghai, China; NYU-ECNU Institute of Brain and Cognitive Science at NYU Shanghai, China; Department of Psychology, New York University, USA. Electronic address: xing.tian@nyu.edu.
authors.forename: Xing
authors.initials: X
authors.lastname: Tian
authors.affiliation: Department of Psychology, New York University, USA.
authors.forename: Jean Mary
authors.initials: JM
authors.lastname: Zarate
authors.affiliation: Department of Psychology, New York University, USA; Department of Neuroscience, Max Planck Institute for Empirical Aesthetics (MPIEA), Germany.
authors.forename: David
authors.initials: D
authors.lastname: Poeppel
mesh_terms: D000328:Adult; D001303:Auditory Cortex / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008568:Memory / Q000502:physiology; D013060:Speech / Q000502:physiology*; D013067:Speech Perception / Q000502:physiology*; D055815:Young Adult
keywords: Internal forward model/efference copy/corollary discharge; Memory retrieval; Mental simulation; Prediction; Sensorimotor integration