Summary: | Brain-Computer Interface (BCI) technology utilizes EEG to measure the electrical activity at the scalp to be used for operating an external device. Therefore, understanding the cognitive responses that can be measured through the EEG to use BCIs is important. BCI systems, such as the P300 Speller, rely on detecting Event-Related Potentials (ERPs). ERPs are time-locked responses to internal or external events. Previous research has indicated that viewing different categories of stimuli activate specific brain structures and produce stimuli specific ERPs. Since the BCI’s ability to detect differences in ERPs is important for operating the system, we have conducted a traditional oddball study to examine the ERPs elicited by two categories of stimuli – images of locations and images of graspable tools. Functional MRI studies have shown that images of familiar locations produce brain responses in the parahippocampal place area (PPA). The PPA is a region of the ventromedial surface of the temporal lobe that responds more strongly to visual scenes (i.e. images of familiar landscapes) than to other presented visual stimuli and is sometimes better known as a “mapping area” of the brain. Conversely, the premotor cortex is an area of motor cortex that lies within the frontal lobe and is used to produce neural impulses that control the implementation of movement. In this instance, logical movement of tools, such as a hammer, can be used as a stimulus for the activation of the premotor cortex. While research has indicated the activation of these different regions, there has not been any research comparing the ERPs that may be produced by these two categories of stimuli. Therefore, our study uses an oddball task to determine if these two types of stimuli can produce distinct ERPs. We hypothesized that images of tools will produce a distinct ERP response, specifically the P300 response, at frontal electrode locations that will significantly differ from ERP responses produced by images of locations. Furthermore, we hypothesized that images of locations will produce distinct ERPs at parietal locations compared to images of tools. Preliminary data collected from 20 participants has indicated a difference in the P300 response at central electrode locations produced by the two types of stimuli. As we continue with data collection, we anticipate observing differences at the frontal and parietal locations. This would indicate that activating these different structures with distal proximity may provide more robust ERP responses that could be used for future P300 Speller BCI operation.
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