Invasive BCI
Invasive Brain-Computer Interfaces (BCIs) are systems that establish a direct connection between the brain and an external device through invasive procedures that involve implanting electrodes or sensors directly into the brain tissue. Invasive BCIs provide a more direct and precise access to neural activity, allowing for high-resolution recording and stimulation capabilities. Here are some key aspects and examples of invasive BCIs:
1. Electrocorticography (ECoG): ECoG involves implanting an electrode grid or strip directly onto the surface of the brain, beneath the skull. ECoG provides high spatial and temporal resolution compared to non-invasive techniques like EEG. It is commonly used for applications such as motor control, speech restoration, or seizure detection.
2. Intracortical Recording: Intracortical BCIs involve implanting microelectrode arrays into specific brain regions, allowing for the recording of individual neuron activity. This method provides the highest spatial and temporal resolution among BCIs. Intracortical BCIs are used for advanced motor control, prosthetic limb control, and research purposes to study neural activity at the single-neuron level.
3. Deep Brain Stimulation (DBS): DBS is an invasive BCI technique that involves implanting electrodes deep within the brain, targeting specific regions associated with neurological disorders such as Parkinson's disease or essential tremor. Electrical stimulation delivered through the implanted electrodes helps modulate abnormal neural activity and alleviate symptoms.
4. Epidural Stimulation: Epidural stimulation involves placing electrodes on the outer surface of the dura mater, a protective layer surrounding the brain and spinal cord. This technique is primarily used for spinal cord injury rehabilitation, where electrical stimulation is applied to the spinal cord to enable voluntary movement in paralyzed individuals.
Invasive BCIs offer several advantages, including high spatial and temporal resolution, precise control capabilities, and the ability to access individual neuron activity. However, invasive procedures come with higher risks and ethical considerations compared to non-invasive BCIs. These risks include surgical complications, potential tissue damage, and the need for long-term maintenance and monitoring of implanted devices.
Ongoing research in invasive BCIs focuses on improving electrode technologies, minimizing the invasiveness of procedures, and developing advanced signal processing and decoding algorithms to enhance the performance and safety of the systems. Invasive BCIs have the potential to significantly impact the lives of individuals with severe neurological conditions, enabling them to restore lost functionalities or achieve advanced control over external devices.
