Brain-computer interface: Difference between revisions
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'''Dependent and independent BCIs''' | '''Dependent and independent BCIs''' | ||
The commands that the user sends to the external world through the BCI system do not follow the same output pathways of peripheral nerves and muscles. Instead, a BCI provides the user with an alternative method for acting on the world. The BCIs can be in two different classes: dependent and independent <ref name=”5”></ref>. These terms appeared in 2002, and both are used to describe BCIs that use brain signals for the control of applications. The difference between them is in how they depend on natural CNS output <ref name=”3”></ref>. | The commands that the user sends to the external world through the BCI system do not follow the same output pathways of peripheral nerves and muscles. Instead, a BCI provides the user with an alternative method for acting on the world. The BCIs can be placed in two different classes: dependent and independent <ref name=”5”></ref>. These terms appeared in 2002, and both are used to describe BCIs that use brain signals for the control of applications. The difference between them is in how they depend on natural CNS output <ref name=”3”></ref>. | ||
A dependent BCI uses brains signals that depend on muscle activity <ref name=”3”></ref>, such as in the case of a BCI that present the user with a matrix of letters. Each letter flashes one at a time, and it is the objective of the user to select a specific letter by looking directly at it. This initiates a visual evoked potential (VEP) that is recorded from the scalp. The VEP produced when the right intended letter flashes is greater than the VEPs produced when other letters flash. In this example, the brain’s output channel is EEG, but the generation of the signal that is detected is dependent on the direction of the gaze which, in turn, depends on extraocular muscles and the cranial nerves that activate them <ref name=”5”></ref>. | A dependent BCI uses brains signals that depend on muscle activity <ref name=”3”></ref>, such as in the case of a BCI that present the user with a matrix of letters. Each letter flashes one at a time, and it is the objective of the user to select a specific letter by looking directly at it. This initiates a visual evoked potential (VEP) that is recorded from the scalp. The VEP produced when the right intended letter flashes is greater than the VEPs produced when other letters flash. In this example, the brain’s output channel is EEG, but the generation of the signal that is detected is dependent on the direction of the gaze which, in turn, depends on extraocular muscles and the cranial nerves that activate them <ref name=”5”></ref>. | ||