Sub-second functional imaging by electrical impedance tomography.

Functional imaging of the human brain using electrical impedance tomography (EIT) is reported, where the measurement data were collected over a period of 308 ms. Initiation of the measurement sequence occurred at times ranging from 70 to 740 ms after administration of visual or auditory stimuli to two volunteers. The reconstructed images of conductivity change due to individual visual stimulus events correspond with anatomical regions known to be involved in visual sensory processing and the processing of cognitive reflexes.

Subsecond observations of EIT voltage changes on the human scalp due to brain stimulus.

A pilot study has investigated the feasibility of imaging human brain function using an electrical impedance tomography (EIT) system time-locked to an evoked response (ER) system. A sixteen-electrode planar EIT configuration was used with polar current injection. We report here measurements on two volunteer patients who were fully awake in all tests.