Beyond The Laboratory: Cognitive Markers of Auditory and Visual Selective Attention in Ecologically Valid Environments

• Author / Creator

  Scanlon, Joanna

• There is currently a trend towards measuring brain activity in more ecologically realistic scenarios. Bringing EEG experiments outside of the lab requires understanding of the impact of features of an ecologically valid environment, including visual scenery, sounds, and complex movements. In the first experiment, participants performed an auditory oddball task while cycling outside and sitting in an isolated chamber inside the lab. Significantly increased N1 and decreased P2 amplitudes was observed evoked by both standards and targets during cycling outside. To test the conclusion that this was related to a process of filtering overlapping sounds between the task and environment, a second experiment was performed using sounds inside the lab. Participants performed an auditory oddball task while also listening to concurrent background noises of silence, white noise and outdoor ecological sounds. We replicated the previous effect, finding a significantly increased N1 and decreased P2 when participants performed the task with outdoor sounds and white noise in the background, with the largest differences in the outdoor sound condition. In the third experiment, participants performed a visual oddball task while either viewing a video, or static screen in the background. We again found that ecologically valid background stimuli in the video decreased the P2, compared to the synthetic background stimuli. In a fourth and final experiment, participants were asked to perform the same auditory oddball task while again cycling outside in two different environments: a quiet park and next to a noisy roadway. In this experiment, only the N1 was increased in the noisier environment. This led to the conclusion that the N1 is altered by attention in non-ideal task situations, and the P2 is related to a process of filtering out irrelevant stimuli. Future research needs to focus on these differences in the ERP when experiments are performed outside, in order better understand how the brain works in the real world.

• Subjects / Keywords

  • Cognitive neuroscience
  • selective attention
  • mobile EEG
  • ecological environments

• Graduation date

  Fall 2018

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3GQ6RJ2Z

• License

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