Persistent horizontal and vertical, MR-induced nystagmus in resting state Human Connectome Project data.

Objective: Strong magnetic fields from magnetic resonance (MR) scanners induce a Lorentz force that contributes to vertigo and persistent nystagmus. Prior studies have reported a predominantly horizontal direction for healthy subjects in a 7 Tesla (T) MR scanner, with slow phase velocity (SPV) dependent on head orientation. Less is known about vestibular signal behavior for subjects in a weaker, 3T magnetic field, the standard strength used in the Human Connectome Project (HCP).

Resting State Functional Connectivity Signatures of MRgFUS Vim Thalamotomy in Parkinson's Disease: A Preliminary Study.

Magnetic Resonance-guided high-intensity Focused Ultrasound (MRgFUS) of the thalamic ventral intermediate nucleus (Vim) for tremor has increasingly gained interest as a new non-invasive alternative to standard neurosurgery. Resting state functional connectivity (rs-FC) correlates of MRgFUS have not been extensively investigated yet. A region of interest (ROI)-to-ROI rs-FC MRI "connectomic" analysis focusing on brain regions relevant for tremor was conducted on 15 tremor-dominant patients with Parkinson's disease who underwent MRgFUS.

Human entorhinal cortex represents visual space using a boundary-anchored grid.

When participants performed a visual search task, functional MRI responses in entorhinal cortex exhibited a sixfold periodic modulation by gaze-movement direction. The orientation of this modulation was determined by the shape and orientation of the bounded search space. These results indicate that human entorhinal cortex represents visual space using a boundary-anchored grid, analogous to that used by rodents to represent navigable space.

The human visual cortex response to melanopsin-directed stimulation is accompanied by a distinct perceptual experience.

The photopigment melanopsin supports reflexive visual functions in people, such as pupil constriction and circadian photoentrainment. What contribution melanopsin makes to conscious visual perception is less studied. We devised a stimulus that targeted melanopsin separately from the cones using pulsed (3-s) spectral modulations around a photopic background.