Neuroplasticity in Visual Word Recognition: An Exploration of Learning-Related Behavioural and Neural Changes
Visual word recognition is a cognitive process that remains relatively stable throughout adulthood. Despite this stability, recent research suggests that the system involved is malleable, by showing evidence of behavioural change after lexical decision task (LDT) practice, and of neural differences between-subjects during LDT performance. However, these studies leave the question unanswered as to whether neural change can occur within the visual word recognition system, which would suggest plasticity. We therefore investigated whether neural change accompanies the behavioural change previously found with LDT practice. If found, these neural changes could be due to processes associated with learning, where performance that is initially unskilled and effortful becomes skilled and efficient, and supported by a more specific, honed, and optimized task network. We replicated the British Lexicon Project (BLP), in which participants completed several days of LDT learning. We additionally recorded EEG at three time points to track neural change during LDT learning, and assessed event-related potentials and brain signal complexity. We found response time decreased during LDT learning, replicating the BLP. We also found neural change occurred through N170, P200, N400, and LPC amplitude effects, suggesting alterations to both the general cognitive and specific lexical processes involved in LDT performance. There was also widespread complexity decreases alongside localized increases, suggesting that with learning, LDT processing became more automatic with specific increases in processing flexibility. These findings suggest that the visual word recognition system is dynamic, flexible, and capable of undergoing plastic changes to support more efficient and automatic task performance.
Plasticity, Learning, Visual Word Recognition, Electroencephalography (EEG), Event-Related Potentials (ERPs), Brain Signal Complexity
Cnudde, K. D. (2020). Neuroplasticity in Visual Word Recognition: An Exploration of Learning-Related Behavioural and Neural Changes (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.