Decoding natural scenes based on sounds of objects within scenes using multivariate pattern analysis

Developing cortex is functionally pluripotent: Evidence from blindness

How rigidly does innate architecture constrain function of developing cortex? What is the contribution of early experience? We review insights into these questions from visual cortex function in people born blind. In blindness, occipital cortices are active during auditory and tactile tasks. What 'cross-modal' plasticity tells us about cortical flexibility is debated. On the one hand, visual networks of blind people respond to higher cognitive information, such as sentence grammar, suggesting drastic repurposing. On the other, in line with 'metamodal' accounts, sighted and blind populations show shared domain preferences in ventral occipito-temporal cortex (vOTC), suggesting visual areas switch input modality but perform the same or similar perceptual functions (e.g., face recognition) in blindness. Here we bring these disparate literatures together, reviewing and synthesizing evidence that speaks to whether visual cortices have similar or different functions in blind and sighted people. Together, the evidence suggests that in blindness, visual cortices are incorporated into higher-cognitive (e.g., fronto-parietal) networks, which are a major source long-range input to the visual system. We propose the connectivity-constrained experience-dependent account. Functional development is constrained by innate anatomical connectivity, experience and behavioral needs. Infant cortex is pluripotent, the same anatomical constraints develop into different functional outcomes.

An investigation of the neural association between auditory imagery and perception of complex sounds

Neuroimaging studies have demonstrated that mental imagery and perception share similar neural substrates, however, there are still ambiguities according to different auditory imagery content. In addition, there is still a lack of information regarding the underlying neural correlation between the two modalities. In the present study, we adopted functional magnetic resonance imaging to explore the neural representation during imagery and perception of actual sounds in our surroundings. Univariate analysis was used to assess the differences between the modalities of average activation intensity, and stronger imagery activation was found in sensorimotor regions but weaker activation in auditory association cortices. Additionally, multi-voxel pattern analysis with a support vector machine classifier was implemented to decode environmental sounds within- or cross-modality. Significant above-chance accuracies were found in all overlapping regions in the classification of within-modality, while successful cross-modality classification only was found in sensorimotor regions. Both univariate and multivariate analyses found distinct representation between auditory imagery and perception in the overlapping regions, including superior temporal gyrus and inferior frontal sulcus as well as the precentral cortex and pre-supplementary motor area. Our results confirm the overlapping activation regions between auditory imagery and perception reported by previous studies and suggest that activation regions showed dissociable representation pattern in imagery and perception of sound categories.