Neural prosthetic control signals from plan activity

Abstract

The prospect of assisting disabled patients by translating neural activity from the brain into control signals for prosthetic devices, has flourished in recent years. Current systems rely on neural activity present during natural arm movements. We propose here that neural activity present before or even without natural arm movements can provide an important, and potentially advantageous, source of control signals. To demonstrate how control signals can be derived from such plan activity we performed a computational study with neural activity previously recorded from the posterior parietal cortex of rhesus monkeys planning arm movements. We employed maximum likelihood decoders to estimate movement direction and to drive finite state machines governing when to move. Performance exceeded 90% with as few as 40 neurons.

Free-paced high-performance brain–computer interfaces

“…As noted in the subsections above, there are several key differences between our internally-paced system and that in Shenoy et al (2003). These are summarized below.…”

“…This is because if the predicted appearance time differs from the actual appearance time, then the target estimator will use spike rate data from outside the time range used in building the target prediction model. Note that this differs from the time transition rule in Shenoy et al (2003) since it uses 200 ms of activity instead of 500 ms.…”

“…This differs from the go transition rule in Shenoy et al (2003) since the entire plan period is being used for decoding, as opposed to only the last 500 ms in Shenoy et al (2003).…”

Cognitive Enhancement: Methods, Ethics, Regulatory Challenges

“…Development is rapid, both on the hardware side, where multielectrode recordings from more than 300 electrodes permanently implanted in the brain are currently state-of-the art, and on the software side, with computers learning to interpret the signals and commands (Nicolelis et al 2003;Shenoy et al 2003;Carmena et al 2003). Early experiments on humans have shown that it is possible for profoundly paralyzed patients to control a computer cursor using just a single electrode (Kennedy and Bakay 1998) implanted in the brain, and experiments by Parag Patil and colleagues have demonstrated that the kind of multielectrode recording devices used in monkeys would most likely also function in humans (Peterman et al 2004;Patil et al 2004).…”

Mental causation via neuroprosthetics? A critical analysis

“…Research has been made on interfaces that connect to cognitive cortical signals, and on devices that respond to specific plans and intentions of motor tasks, rather than on the neural execution of those tasks (e.g. Hatsopoulos et al 2004;Musallam et al 2004;Shenoy et al 2003). One could presume that devices functioning on the basis of conscious intentions would prove to be very useful indeed, for such intentions could be executed in a variety of ways, and they could thus allow a variety of different concrete implementations; indeed, the fruitfulness of this approach has recently been demonstrated on a human subject (Aflalo et al 2015).…”