Matching Items (2)
Description
It is important to consider attention when designing and conducting an experiment due to the significant impact it can have on how people process information. This study compared the influence attention can have on performance of an auditory task. Using an EEG system and measuring cortical evoked response potentials (ERPs) the assumptions about keeping eyes open during passive listening tasks which related to the low attention parameter of MMN, as well as requiring an active response for the high attention parameter of the P300 were tested. The hypotheses were that the presence of an active, focused component will increase the magnitude of the P300 (as is generally accepted), that the presence of an active, focused component will decrease the magnitude of the MMN (as is currently debated), and that closed eyes would diminish the magnitude of both components (as also is currently debated). The presence of significant values for both the P300 amplitude and P300 adaptive mean indicated a successful causal link between the presence of an active condition and an increased P300 waveform, while the high individual variability present throughout the data focus the scope of future study on MMN and P300.
ContributorsKonduri, Gopi (Author) / Peter, Beate (Thesis director) / Lancaster, Hope (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Objective: Previous studies have observed that adults with dyslexia display a reduced N1 gating when exposed to repetitive stimuli. Robust gating is associated with the ability to recognize familiar stimuli and identify the stimuli that will need novel memory representations formed. This study investigates if the mismatch negativity component in electroencephalographic-produced Event-Related Potentials (ERPs) is affected as well by diminished memory forming in adults with dyslexia. Additionally, signal/ noise processing for auditory-based memory recollection and thus word learning is explored. Methods: Nineteen adults with dyslexia and 18 adult controls participated in a classic auditory oddball electroencephalographic experiment here referred to as DIFF, to indicate that the tones differed in frequency, while incorporating a decision-making task that signified participant tonal discrimination. Mismatch Negativity (MMN) amplitudes (AMPs) and latencies were collected from ERPs. Behavioral data consisting of reaction time (RT) and accuracy (ACC) of tone choice were documented.
Results: Group differences for accuracy and reaction time in the DIFF task were highly significant. The dyslexic group produced longer reaction times and with less accuracy than the control group. The Mismatch Negativity amplitude and latency collected did not differ significantly between groups, however, correlations to other variables obtained from similar studies consisting of the same participant group were observed. Linear regression models indicated predictions for accuracy and reaction time results based upon WID scores (Word Identification Test) and SWE scores (Sight Word Efficiency) respectfully.
Conclusions: Neural processing speed and the ability to form permanent memory representations of auditory sound bites for retrieval is dampened in dyslexic populations.
Significance: To better illuminate and understand the neural mechanisms of dyslexia, specifically auditory processing, with the goal of improving outcomes in individuals with dyslexia through more efficient therapy treatment options.
ContributorsAbrams, Gabrielle Renee (Author) / Peter, Beate (Thesis advisor) / Rogalsky, Corianne (Committee member) / Rao, Aparna (Committee member) / Arizona State University (Publisher)
Created2022