Holographically patterned activation using photo-absorber induced neural–thermal stimulation

Abstract

Holographically patterned PAINTS could potentially provide a means for minimally intrusive control over neuronal dynamics with a high level of spatial and temporal selectivity.

Thermal Transients Excite Neurons through Universal Intramembrane Mechanoelectrical Effects

“…This study explored the effects of temperature changes on membrane capacitance and its associated currents in a joint attempt to clarify the experimental results of a key recent study [16] and to pave the way towards predictive modeling of INS [2][3][4][5][6][7][8][9][10][11][12][13][14][15] and other thermal neurostimulation techniques [18][19][20], which could potentially facilitate the development of more advanced and multimodal methods for neural circuit control. Another key motivation to pursue this problem came from our noting the very similar temperature-related capacitance rates of change observed in very different model systems [ Fig.…”

“…5(a) of Ref. [18]], are inserted into model layer V cortical neurons. Reexamining in terms of the new biophysical model, α is almost entirely dependent on the temperature derivative of the membrane capacitance multiplied by the surface charge-related potential, allowing us to estimate the surface charge difference, Δσ ¼ σ i − σ o , as −0.107 C=m 2 plus maximal deviation ≈5% (note that α is identified as the neural membrane's thermoelectric capacitance; see Secs.…”

“…To estimate the intracellular and extracellular surface charge difference in neurons, we used our recent discovery that temperature transients excite neurons through formation of membrane currents that are proportional to the temperature time derivative, I L ¼ −α½ðdTÞ=dt , where α is a positive constant [18], which according to the GCS-based model actually equals to the effective thermoelectric capacitance:…”

“…A multitude of INS-related studies explored the ability of short-wave infrared (IR) pulses to stimulate neural structures including peripheral [3,4] and cranial nerves [5][6][7][8][9][10], retinal and cortical neurons [10][11][12], as well as cardiomyocytes [13,14]. It is stipulated that the INS phenomenon is mediated by temperature transients induced by IR absorption [15][16][17]; such transients can alternatively be induced using other forms of photoabsorption [18][19][20], or potentially by any other physical form of thermal neurostimulation that can be driven rapidly enough [21,22]. Shapiro et al [16] showed that these rapid temperature variations are directly accompanied by changes in the cell membrane's capacitance and resulting displacement currents which are unrelated to specific ionic channels; their findings on the thermal capacitance increase have been supported by experiments from several additional groups [19,20,[23][24][25].…”

Gold Nanorod-assisted Optical Stimulation of Neuronal Cells

“…Similarly, Farah et al demonstrated electrical stimulation of rat cortical neurons with black micro-particles in vitro. They showed cell-level precision in stimulation using pulse durations on the order of hundreds of µs and energies in the range of µJ, potentially allowing for faster repetition rates 6 .…”