Active C4 electrodes for local field potential recording applications

Extracellular neural recording, with multi-electrode arrays (MEAs), is a powerful method used to study neural function at the network level. However, in a high density array, it can be costly and time consuming to integrate the active circuit with the expensive electrodes. In this paper, we present a 4 mm × 4 mm neural recording integrated circuit (IC) chip, utilizing IBM C4 bumps as recording electrodes, which enable a seamless active chip and electrode integration. The IC chip was designed and fabricated in a 0.13 μm BiCMOS process for both in vitro and in vivo applications. It has an input-referred noise of 4.6 μV rms for the bandwidth of 10 Hz to 10 kHz and a power dissipation of 11.25 mW at 2.5 V, or 43.9 μW per input channel. This prototype is scalable for implementing larger number and higher density electrode arrays. To validate the functionality of the chip, electrical testing results and acute in vivo recordings from a rat barrel cortex are presented.R01 NS072385 - NINDS NIH HHS; 1R01 NS072385 - NINDS NIH HH

Design of a 5-bit algorithmic A/D converter for potential use in a wireless neural recorder application

The constant endeavor to measure and record neural signals from the human brain and anticipate the results to figure out the mechanism which governs the functionality of our brain and its true behavior is the major driving force behind this thesis. Neural recording integrated circuits (ICs) are often inserted directly into the brain, with a set of probes for sensing these action potentials (and local field potentials), and appropriate circuitry for amplifying the neural signals (Pre-Amp), sampling and converting the analog signals to digital (ADC) and transmitting the resulting digital signal (Transmitter) to a nearby reader instrument (Receiver). Action potentials are comprised of signals typically looking like spikes having a peak voltage of 1-2mV, whereas local field potentials are continuous signals generally having an amplitude of around 100-200μV often with a dc component of several mV. Fourier analysis of action potentials and local field potentials show frequency components in the range of 0.1 Hz up to 10kHz. This thesis proposes a low-power 5-bit algorithmic A/D converter to feed a 5-stage serial shift register for use in sampling and converting a presumed neuron action potential signal at the rate of 20k samples/sec. In addition to that, a low-power preamp with at least 40dB gain and a low-pass type spectrum having a unity-gain frequency of at least 20MHz is used to amplify the input signal. The algorithmic A/D converter includes a sample-and-hold circuit for sampling the analog action potential spike at a rate of 20kHz. The ADC utilizes an X2 gain circuit based on a capacitive redistribution technique. A less complex circuit in terms of dependency on Capacitor sizing and their non-ideal effects is the key factor for selecting this type of ADC which can be used for neural recording applications. All the circuits are designed based on the IBM/Global Foundries 8HP 130nm BiCMOS technology

Seizure detection and neuromodulation: A summary of data presented at the XIII conference on new antiepileptic drug and devices (EILAT XIII)

The Thirteenth Eilat Conference on New Antiepileptic Drugs and Devices (EILAT XIII) took place in Madrid, Spain from June 26th to 29th 2016. For the first time, the last day of the conference focused solely on new medical devices and neuromodulation. The current article summarises the presentations of that day, focusing first on EEG- and ECG based methods and devices for seizure detection. These methodologies form the basis for novel cardiac-based methods of vagal nerve and responsive deep brain stimulation that rely on the prediction or early detection of seizures and that are also included in this article

IEEE Transactions on Biomedical Circuits And Systems: Vol. 7, No. 5, October 2013

1. Guest Editorial-Special Issue on Selected Papers From BioCAS 2012 / T. -P. Jung, P. Haflinger 2. A Fully-Asynchronus Low-Power Implantable Seizure Detector for Self Triggering Treatment / M. Mirzaei, M. T. Salam, D. K. Nguyen, M. Savan 3. A 155 uW 88-dB Discrete-Time AE Modulator for Digital Hearing Aids Exploiting a Summing SAR ADC Quantizer / S. Porazzo, A. Morgado, D. San Segundo Bello, F. Cannillo, C. Van Hoof, R. F. Yacioglu, A. H. M. Van Roermund, E. Cantatore 4. A 0.7-V 14.4-u W 3-Lead Wireless ECG SoC / M. Kayatzadeh, X. Zhang, J. Tan, W. -S. Liew, Y. Lian 5. Opto-uECoG Array : A Hybrid Neural Interface With Transparent uECoG Electrode Array and Integrated LEDs for Optogenetics / K. Y. Kwon, B. Sirowatka, A. Weber, W. Li 6. Massively-Parallel Neuromonitoring and Neurostimulation Rodent Headset With Nanotextured Flexible Microelectrodes / A. Bagheri, S. R. I. Gabran, M. T. Salam, J. L. Perez Velasquez, R. R. Mansour, M. M. A. Salama, R. Gonev 7. A Compact, Low Input Capacitance Neural Recording Amplifier / K. A. Ng, Y. P. Xu 8. Rapid Detection of E.coli Bacteria Using Potassium-Sensitive FETs in CMOS / N. Nikkhoo, P. G. Gulak, K. Maxwell 9. Neuron Array With Plastic Synapses and Programmable Dendrites / S. Ramakrishnan, R. Wunderlich, J. Hasler, S. George 10. CMOS Spectrally-Multiplexed FRET-on-a-Chip for DNA Analysis / D. Ho, M. O. Noor, U. J. Krull, G. Gulak, R. Genov Etc