Synaptic Communication Engineering for Future Cognitive Brain–Machine Interfaces

Abstract

Disease-affected nervous systems exhibit anatomical or physiological impairments that degrade processing, transfer, storage, and retrieval of neural information leading to physical or intellectual disabilities. Brain implants may potentially promote clinical means for detecting and treating neurological symptoms by establishing direct communication between the nervous and artificial systems. Current technology can modify neural function at the supracellular level as in Parkinson's disease, epilepsy, and depression. However, recent advances in nanotechnology, nanomaterials, and molecular communications have the potential to enable brain implants to preserve the neural function at the subcellular level which could increase effectiveness, decrease energy consumption, and make the leadless devices chargeable from outside the body or by utilizing the body's own energy sources. In this study, we focus on understanding the principles of elemental processes in synapses to enable diagnosis and treatment of brain diseases with pathological conditions using biomimetic synaptically interactive brain-machine interfaces. First, we provide an overview of the synaptic communication system, followed by an outline of brain diseases that promote dysfunction in the synaptic communication system. We then discuss technologies for brain implants and propose future directions for the design and fabrication of cognitive brain-machine interfaces. The overarching goal of this paper is to summarize the status of engineering research at the interface between technology and the nervous system and direct the ongoing research towards the point where synaptically interactive brain-machine interfaces can be embedded in the nervous system.

Stochastic reaction and diffusion systems in molecular communications: Recent results and open problems

“…General Survey [21] Applications in Medicine [22,23,24] Applications in Biology [11,10,25,26] Applications in Nanonetworking [27,28,29] Channel Models [30] Information Theoretic Limits [14,13] Modulation and Equalization [8,9,31] Synaptic Communication [32] The vast majority of the existing surveys have focused on applications. A key novel aspect of this survey is its focus on methodology.…”

Molecular Communications in Viral Infections Research: Modeling, Experimental Data, and Future Directions

“…For intra-body, the link between virus replication and tissue response has yet to be thoroughly investigated. For example, the interactions of the virus with neural communications [130], [13], or calcium signalling in different tissues or organs (especially the epithelium) [131], [132], [133], can provide further understanding between the virus and hosts interactions using molecular signals as infection information carriers. As we know from the literature, the human immune response is triggered after the human body recognises the presence of infectious agents, foreign to the body itself [134].…”

Analytical Investigation of Long-Time Diffusion Dynamics in a Synaptic Channel With Glial Cells

“…We have two key observations at this point: 1) All dimensionless parameters are much smaller than 1 for our range of interest. 2) For λ −1 decay ∼ O( ms), which corresponds to the biological decay time of milliseconds [10], we require that φ 11 1 and α 1 < 1. The second one is a particularly robust observation, as D, L, and R S uniquely constrain φ 11 and α 1 to be small in (12) and their values are well-known within some intervals [10].…”

“…38]. By assumptions of the Taylor approximation φ 11 1 so that D L 2 φ 2 11 D L 2 , which satisfies the diffusion related part of the inequalities. For the reaction part, if we set k D = 0 (as in [6]) and k G = 0 (reflecting boundary), this reduces to k B kR kR+kF +LkB < k B kR kR+kF , which satisfies the reaction related part of the inequality in [6, eq.…”

“…Therefore, understanding the dynamics of diffusion inside the synaptic channel can be beneficial for our grasp of mental disorders. While the synaptic process has already been extensively considered in the biology literature, for example see [10], focusing on the molecular synaptic channel from a communication engineering perspective can pave the way for handling many open problems, as comprehensively explained in [11]. One of these open problems is the analytical derivation of CIR of synaptic communication, which has been examined recently by omitting neurotransmitter degradation by enzymes and for a simplified geometry [6], [12].…”