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Brain & Heart Predictive modeling using electroencephalogram

from creating devices to creating systems that address The brain’s signaling rhythms are typically categorized
the challenges that individuals with physical limitations into bands according to their frequencies. Although
encounter. In particular, individuals with catastrophic the names for these frequency ranges are arbitrary, they
neuromuscular injuries or progressive neurodegenerative are commonly used to imply that the rhythmic activity
diseases, which impair the user’s ability to move voluntarily observed at those frequencies holds biological significance
but leave their brain intact, have a pressing need for such and follows a particular pattern of distribution across the
systems. Recent advances in BCI research have aligned scalp. The typical placement of electrodes is presented in
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with trends in other human-computer interaction (HCI) Figure 1A and B. 8
studies in narrowing their attention. 2 BCIs focus on eliciting brain signals associated with
The initial step in building a BCI is acquiring reliable specific types of thought and translating them into machine
electroencephalogram (EEG) signals. Understanding commands. It represents a form of communication where
the brain’s physiology and anatomy in depth is crucial. thoughts, rather than conventional nerves and muscles,
This knowledge aids in pinpointing the optimal spots for serve as the means to transmit information. In the early
sensing nodes and taking the necessary measurements. The stages of BCI research and development, researchers
human brain contains roughly one hundred billion nerve concentrated on creating assistive devices for individuals
cells (neurons), each capable of collecting and transmitting with physical disabilities. However, the demand for BCIs
electrochemical signals to other neurons, sometimes over and public awareness surrounding them has surged,
very long distances. By relaying signals from the brain to leading researchers to explore their potential applications
the rest of the body’s neurons, the brain directs cognitive across various fields beyond medicine. Future user-
and motor processes. The two hemispheres of the brain communication systems may require offering input on
exhibit differences in specialization and processing the user’s mental state or intentions in addition to their
styles, with certain functions being more dominant in physical state, representing one of the most discussed
one hemisphere over the other. However, cognitive tasks possible uses for BCIs. 9
typically involve interactions between both hemispheres, Both dependent and independent BCIs are common.
highlighting their interconnectedness and collaborative In dependent BCIs, conventional output pathways in the
nature. For instance, tasks requiring imagination and brain are bypassed, whereas autonomous BCIs operate
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creativity, such as recognizing faces, expressing emotions, without reliance on the brain’s typical output pathways.
and reading emotions, tend to be associated with the In a dependent BCI, such as one utilizing a sample matrix
right brain, while logical and analytical processes, such as of blinking letters, the eye’s gaze direction determines the
critical thinking and reasoning, tend to be associated with direction of the EEG signal. In contrast, an independent
the left. Most motor and sensory signals between the brain BCI’s EEG signal is based on the user’s intention to select
and the body travel across the cerebral midline, with the a particular letter. To operate BCIs successfully, users must
right hemisphere sensing and controlling the left side of learn and maintain the skill of regulating different types
the body and vice versa. 4 of electrophysiological signals to achieve their desired

Recorded signals are the numerical representation interaction outcomes. The BCI must then translate this
of voltage fluctuations caused by the movement of regulation into machine commands that carry out the
electrochemical currents within the brain’s neurons. The user’s intended action. Consequently, users must train
term “electroencephalography” describes the method by themselves to deliberately control their brain waves. 10
which this activity is captured along the scalp. Metal disks There are currently two methods for teaching users
called electrodes are applied to the scalp and used to record to regulate their own brain waves. The first type requires
signals. These electrodes are moistened with a conducting users to engage in targeted mental activities, like motor
gel or liquid to keep them in contact with the underlying imagery, to produce detectable brain activity. By mentally
electrical signals. Some commercial dry EEG headsets, imagining sequences of rest and movement – for example,
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however, are starting to make an appearance in the BCI raising and lowering one’s arms or performing high
world, and these could be used to capture data and transfer kicks – the user can send binary data to a computer. The
it to a computer through a wireless medium. Electrode second technique, called operant conditioning, involves
patterns of EEG signals indicate ongoing brain activity, providing immediate feedback to the user as they attempt
with the varying signal strengths reflecting the effects of to control the interface. As long as the goal is met, it does
the body’s mental and physical states. EEG signals over the not matter what a user is thinking about. Eventually, after
brain’s surface have been recorded at intensities between 0 multiple sessions, the user will be able to complete the task
and 200 µV. 6 without thinking about the interface at all. However, many

Volume 2 Issue 2 (2024) 2 doi: 10.36922/bh.2819