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auditory information into vibrations in the range perceivable by human
Somatosensation.
In the fourth chapter we used both small and large piezoelectric stimulators to
stimulate individual fingers, the hip and the foot of subjects in the MR scanner. We were
able to correctly decode touches to individual fingers 68 percent of the time using fMRI
multivoxel pattern analysis; this accuracy could approach 100% using a higher resolution
method such as intracortical recordings. It would then be possible to provide high-
resolution artificial somatosensory percepts, which could be built into a prosthetic hand
to Providetactile feedback Similar to a biological hand.
In chapter five we conducted psychophysical experiments using the piezoelectric
stimulators to investigate the impact of auditory stimuli on the detection and
perception of tactile stimuli. We found that auditory stimuli aid in the detection of
near-threshold tactile stimuli, and the auditory tones influence the perception of
Vibrotactilefrequency.
ChaptersixdescribedhowweadaptedacommerciallyavaiIabIeTMSsystemfor
use in an MRI scanner. We demonstrated that our system works well enough to detect
the hemodynamic response in human subjects while simultaneously delivering TMS
pulses. In future experiments, we will disrupt somatosensory cortex with TMS and study
how this affects responses to somatosensory stimuli delivered with the piezoelectric
stimulators.
The final chapter covered improvements of a system for concurrent
microrecording and microstimulation during an industrial internship at Blackrock