Copyright 2016 Biomedical Microdevices Laboratory
 PT McCarthy, KJ Otto, and MP Rao. Biomed Microdevices 13(3):503-515, 2011.
 PT McCarthy, MP Rao, and KJ Otto. J Neural Engr 8(4):046007 (9pp), 2011.
Top: Scanning electron micrograph of
Ti-based penetrating microelectrode .
noise-evoked, peri-stimulus time
histograms from the auditory cortex (top
2 rows) and thalamus (bottom 2 rows) of
an anesthetized rat. The green bar along
the x-axis reflects the timing of the
broadband acoustic noise stimulus .
Research in this thrust focuses on addressing
fundamental reliability limitations that may
ultimately constrain the clinical translation of
penetrating microelectrodes used for neural
By providing means for directly interacting with
neural tissues, penetrating microelectrodes have
shown promise for restoring neurological functions
lost to disease, stroke, or injury. However, the
intrinsic brittleness of silicon, the material most
commonly used for the manufacture of such
devices, creates non-negligible probability for
fracture-based fragmentation within the brain.
This therefore motivates the development of
means for mitigating this hazard, given the
potential severity and resulting adverse impact
this could have on future clinical viability.
The Ti-based microelectrodes shown here seek to
address this limitation. Thus far, we have
demonstrated that these devices: a) provide
potential for enhanced safety, due to their
graceful, plasticity-based failure mode ; b)
posses sufficient stiffness for reliable cortical
penetration ; c) provide recording performance
comparable to that of commercially-available
devices ; and d) allow, for the first time,
simultaneous recording of multi-unit data and
isolated action potentials in auditory cortex and
KJ Otto, BME, Purdue University
Showalter Research Trust (PI: Rao)