Categories of Neurotechnology
A multitude of neurotechnologies, with different maturity levels, belong to one or more types of medical neurotechnology. For example, there may be technologies for physical modification that also involve stimulation. In that case, the ethical, legal, social, and cultural issues for both classifications should be considered.
Some neurotechnologies have been used for decades and are part of the common medical practice to diagnose or treat neural pathologies, while others are more recent and currently available only in clinical or preclinical trials. In this section, we provide some examples for each of the several types of medical neurotechnologies, while a more exhaustive (but not comprehensive) list of existing and anticipated technologies can be found in the tables at the end of each type of medical neurotechnology.
Recording/Sensing
These are neurotechnologies capable of capturing information about the functional activity of the nervous system. For example, action potentials, ionic currents, activity-dependent blood flow and/or oxygenation, or other signals that reveal information about the activity of the central and/or peripheral nervous system.
Stimulating/Actuating
These are neurotechnologies capable of stimulating, inhibiting, or modulating the activity of the nervous system.
Closed-loop Operation
These are neurotechnologies that combine recording/sensing with stimulation/actuation where the recorded signals (or other relevant biomarkers sensed by implanted or extracorporeal devices) are used to regulate the stimulation/modulation in a feedback control loop. In other types of non-stimulating closed-loop technologies, the user’s biomarkers are used to control external devices and sensory feedback (such as visual feedback) is used by the user to modulate its own biomarkers to better regulate the therapeutic effect.
Direct Physical and Biological Modification
These are neurotechnologies that physically alter the nervous system by modifying physiology, and/or specific systems or sub-systems. Examples include genetic manipulation combined with associated stimulation and/or recording devices (e.g., optogenetics combined with optical stimulators), devices or technologies whose primary function is to alter neural cells and/or their connections (e.g., gamma knife).
