Leveraging shared connectivity to aggregate heterogeneous datasets into a common response space

Neuroimage. 2020 Aug 15;217:116865. doi: 10.1016/j.neuroimage.2020.116865. Epub 2020 Apr 21.

Abstract

Connectivity hyperalignment can be used to estimate a single shared response space across disjoint datasets. We develop a connectivity-based shared response model that factorizes aggregated fMRI datasets into a single reduced-dimension shared connectivity space and subject-specific topographic transformations. These transformations resolve idiosyncratic functional topographies and can be used to project response time series into shared space. We evaluate this algorithm on a large collection of heterogeneous, naturalistic fMRI datasets acquired while subjects listened to spoken stories. Projecting subject data into shared space dramatically improves between-subject story time-segment classification and increases the dimensionality of shared information across subjects. This improvement generalizes to subjects and stories excluded when estimating the shared space. We demonstrate that estimating a simple semantic encoding model in shared space improves between-subject forward encoding and inverted encoding model performance. The shared space estimated across all datasets is distinct from the shared space derived from any particular constituent dataset; the algorithm leverages shared connectivity to yield a consensus shared space conjoining diverse story stimuli.

Keywords: Data harmonization; Functional connectivity; Hyperalignment; Naturalistic stimuli; fMRI.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Acoustic Stimulation
  • Adolescent
  • Adult
  • Algorithms
  • Auditory Cortex / diagnostic imaging
  • Auditory Cortex / physiology
  • Auditory Perception
  • Brain Mapping
  • Databases, Factual
  • Female
  • Humans
  • Individuality
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Models, Neurological
  • Models, Psychological
  • Nerve Net / diagnostic imaging*
  • Nerve Net / physiology*
  • Semantics
  • Young Adult