Cognitive Enhancement and Brain-Computer Interfaces: Potential Boundaries and Risks.

Electroencephalography (EEG) systems and brain-computer interfaces (BCIs) are terms frequently involved in the field of neurological research. Under a technological point of view, BCI is considered to be a significant achievement within the frame of learning disabilities rehabilitation. Nevertheless, the specifications for efficient use for cognitive enhancement and its potential boundaries are under concern. Author's main objective is to discuss BCI concrete components and potential advances as well as depict potential limitations while using technological devices within the frame of the learning procedure. Within this context, requirements, advantages, possible addiction risks, and boundaries regarding the specifications for brain-computer interfaces and technology in order to serve long-term research and developmental learning goals are discussed.

Embodiment and Estrangement: Results from a First-in-Human "Intelligent BCI" Trial.

While new generations of implantable brain computer interface (BCI) devices are being developed, evidence in the literature about their impact on the patient experience is lagging. In this article, we address this knowledge gap by analysing data from the first-in-human clinical trial to study patients with implanted BCI advisory devices. We explored perceptions of self-change across six patients who volunteered to be implanted with artificially intelligent BCI devices. We used qualitative methodological tools grounded in phenomenology to conduct in-depth, semi-structured interviews. Results show that, on the one hand, BCIs can positively increase a sense of the self and control; on the other hand, they can induce radical distress, feelings of loss of control, and a rupture of patient identity. We conclude by offering suggestions for the proactive creation of preparedness protocols specific to intelligent-predictive and advisory-BCI technologies essential to prevent potential iatrogenic harms.

Chronic multisite brain recordings from a totally implantable bidirectional neural interface: experience in 5 patients with Parkinson's disease.

OBJECTIVE Dysfunction of distributed neural networks underlies many brain disorders. The development of neuromodulation therapies depends on a better understanding of these networks. Invasive human brain recordings have a favorable temporal and spatial resolution for the analysis of network phenomena but have generally been limited to acute intraoperative recording or short-term recording through temporarily externalized leads. Here, the authors describe their initial experience with an investigational, first-generation, totally implantable, bidirectional neural interface that allows both continuous therapeutic stimulation and recording of field potentials at multiple sites in a neural network. METHODS Under a physician-sponsored US Food and Drug Administration investigational device exemption, 5 patients with Parkinson's disease were implanted with the Activa PC+S system (Medtronic Inc.). The device was attached to a quadripolar lead placed in the subdural space over motor cortex, for electrocorticography potential recordings, and to a quadripolar lead in the subthalamic nucleus (STN), for both therapeutic stimulation and recording of local field potentials. Recordings from the brain of each patient were performed at multiple time points over a 1-year period. RESULTS There were no serious surgical complications or interruptions in deep brain stimulation therapy. Signals in both the cortex and the STN were relatively stable over time, despite a gradual increase in electrode impedance. Canonical movement-related changes in specific frequency bands in the motor cortex were identified in most but not all recordings. CONCLUSIONS The acquisition of chronic multisite field potentials in humans is feasible. The device performance characteristics described here may inform the design of the next generation of totally implantable neural interfaces. This research tool provides a platform for translating discoveries in brain network dynamics to improved neurostimulation paradigms. Clinical trial registration no.: NCT01934296 (clinicaltrials.gov).

Understanding the Role of Innate Immunity in the Response to Intracortical Microelectrodes.

Intracortical microelectrodes exhibit enormous potential for researching the nervous system, steering assistive devices and functional electrode stimulation systems for severely paralyzed individuals, and augmenting the brain with computing power. Unfortunately, intracortical microelectrodes often fail to consistently record signals over clinically useful periods. Biological mechanisms, such as the foreign body response to intracortical microelectrodes and self-perpetuating neuroinflammatory cascades, contribute to the inconsistencies and decline in recording performance. Unfortunately, few studies have directly correlated microelectrode performance with the neuroinflammatory response to the implanted devices. However, of those select studies that have, the role of the innate immune system remains among the most likely links capable of corroborating the results of different studies, across laboratories. Therefore, the overall goal of this review is to highlight the role of innate immunity signaling in the foreign body response to intracortical microelectrodes and hypothesize as to appropriate strategies that may become the most relevant in enabling brain-dwelling electrodes of any geometry, or location, for a range of clinical applications.

Microelectrode implantation in motor cortex causes fine motor deficit: Implications on potential considerations to Brain Computer Interfacing and Human Augmentation.

Intracortical microelectrodes have shown great success in enabling locked-in patients to interact with computers, robotic limbs, and their own electrically driven limbs. The recent advances have inspired world-wide enthusiasm resulting in billions of dollars invested in federal and industrial sponsorships to understanding the brain for rehabilitative applications. Additionally, private philanthropists have also demonstrated excitement in the field by investing in the use of brain interfacing technologies as a means to human augmentation. While the promise of incredible technologies is real, caution must be taken as implications regarding optimal performance and unforeseen side effects following device implantation into the brain are not fully characterized. The current study is aimed to quantify any motor deficit caused by microelectrode implantation in the motor cortex of healthy rats compared to non-implanted controls. Following electrode insertion, rats were tested on an open-field grid test to study gross motor function and a ladder test to study fine motor function. It was discovered that rats with chronically indwelling intracortical microelectrodes exhibited up to an incredible 527% increase in time to complete the fine motor task. This initial study defines the need for further and more robust behavioral testing of potential unintentional harm caused by microelectrode implantation.

Cortical Brain-Computer Interface for Closed-Loop Deep Brain Stimulation.

Essential tremor is the most common neurological movement disorder. This progressive disease causes uncontrollable rhythmic motions-most often affecting the patient'sdominant upper extremity-thatoccur during volitional movement and make it difficult for the patient to perform everyday tasks. Medication may also become ineffective as the disorder progresses. For many patients, deep brain stimulation (DBS) of the thalamus is an effective means of treating this condition when medication fails. In current use, however, clinicians set the patient's stimulator to apply stimulation at all times-whether it is needed or not. This practice leads to excess power use, and more rapid depletion of batteries that require surgical replacement. In this paper, for the first time, neural sensing of movement (using chronically implanted cortical electrodes) is used to enable or disable stimulation for tremor. Therapeutic stimulation is delivered onlywhen the patient is actively using their effected limb, thereby reducing the total stimulation applied, and potentially extending the lifetime of surgically implanted batteries. This paper, which involves both implanted and external subsystems, paves the way for fully-implanted closed-loop DBS in the future.

The future of psychiatry: brain devices.

Recent advances in deep brain stimulators and brain-machine interfaces have greatly expanded the possibilities of neuroprosthetics and neuromodulation. Together with advances in neuroengineering, nanotechnology, molecular biology and material sciences, it is now possible to address fundamental questions in neuroscience in new, more powerful ways. It is now possible to apply these new technologies in ways that range from augmenting and restoring function to neuromodulation modalities that treat neuropsychiatric disorders. Recent developments in neuromodulation methods offer significant advantages and potential clinical benefits for a variety of disorders. Here we describe the current state of the art in neuromodulation methods, and some advances in brain-machine interfaces, describing the advantages and limitations of the clinical applications of each method. The future applications of these new methods and how they will shape the future of psychiatry and medicine, along with safety and ethical implications, are also discussed.

Informed consent in implantable BCI research: identification of research risks and recommendations for development of best practices.

OBJECTIVE: Implantable brain-computer interface (BCI) research promises improvements in human health and enhancements in quality of life. Informed consent of subjects is a central tenet of this research. Rapid advances in neuroscience, and the intimate connection between functioning of the brain and conceptions of the self, make informed consent particularly challenging in BCI research. Identification of safety and research-related risks associated with BCI devices is an important step in ensuring meaningful informed consent. APPROACH: This paper highlights a number of BCI research risks, including safety concerns, cognitive and communicative impairments, inappropriate subject expectations, group vulnerabilities, privacy and security, and disruptions of identity. MAIN RESULTS: Based on identified BCI research risks, best practices are needed for understanding and incorporating BCI-related risks into informed consent protocols. SIGNIFICANCE: Development of best practices should be guided by processes that are: multidisciplinary, systematic and transparent, iterative, relational and exploratory.

Distribution and Morphology of Calcium-Binding Proteins Immunoreactive Neurons following Chronic Tungsten Multielectrode Implants.

The development of therapeutic approaches to improve the life quality of people suffering from different types of body paralysis is a current major medical challenge. Brain-machine interface (BMI) can potentially help reestablishing lost sensory and motor functions, allowing patients to use their own brain activity to restore sensorimotor control of paralyzed body parts. Chronic implants of multielectrodes, employed to record neural activity directly from the brain parenchyma, constitute the fundamental component of a BMI. However, before this technique may be effectively available to human clinical trials, it is essential to characterize its long-term impact on the nervous tissue in animal models. In the present study we evaluated how chronic implanted tungsten microelectrode arrays impact the distribution and morphology of interneurons reactive to calcium-binding proteins calbindin (CB), calretinin (CR) and parvalbumin (PV) across the rat's motor cortex. Our results revealed that chronic microelectrode arrays were well tolerated by the nervous tissue, with recordings remaining viable for up to 6 months after implantation. Furthermore, neither the morphology nor the distribution of inhibitory neurons were broadly impacted. Moreover, restricted microglial activation was observed on the implanted sites. On the whole, our results confirm and expand the notion that tungsten multielectrodes can be deemed as a feasible candidate to future human BMI studies.

Physiological challenges for intracortical electrodes.

The clinical use of chronic electrode implants for measurement or stimulation of neuronal activity has increased over the past decade with the advent of deep brain stimulation and the use of brain-computer interfaces. However, despite the wide-spread application of electrode implants, their chronic use is still limited by technical difficulties. Many of the reported issues, ranging from short-circuits to loss of signal due to increased electrical impedance, may be traced back to the reaction of the cortical tissue to the implanted devices: the foreign body response (FBR). This response consists of several phases that ultimately result in neuronal loss and the formation of a dense glial sheath that encapsulates the implant. Empirical evidence suggests that reducing the FBR has a positive effect on the electrical properties of implants, which can potentially expand their clinical use by improving their chronic usability. The primary focus of this work is to review the consequences of the FBR and recent developments that can be considered to control and limit its development. We will discuss how the choice of device material and electrode-architecture influences the tissue reaction, as well as modifications that allow for less stiff implants, increase electrode conductivity, or improve the implant-tissue integration. Several promising biological solutions include the local release of anti-inflammatory compounds to weaken the initial inflammatory phase of the FBR, as well as methods to diminish the negative effects of the glial sheath on neuronal regrowth.