Abstract We present a novel approach for endoscopic calcium imaging in the marmoset extrastriate visual cortex, combining a chronically implanted microprism lens with an integrated injection cannula. This method achieved stable, longitudinal imaging of visually responsive GCaMP-expressing neurons over multiple weeks. Using a head-mounted miniscope in two subjects, we repeatedly presented naturalistic visual stimuli and longitudinally tracked the activity of more than one hundred neurons across sessions within an 800-μm2 field of view. Stably monitored neurons in cortical areas V3 and MT responded reliably to visual images and movies over periods up to three weeks. Cells having different visual response preferences were spatially intermixed. These results demonstrate the feasibility of longitudinal calcium imaging in the primate visual cortex using a single-surgery, integrated lens-cannula approach, and provide initial insights into single neuron response stability and diversity to naturalistic stimuli in mid-level cortical visual areas.
Park et al. (Thu,) studied this question.