Document Type


Degree Name

Master of Science (MSc)



Program Name/Specialization

Cognitive Neuroscience


Faculty of Science

First Advisor

Todd R. Ferretti

Advisor Role



The current research examined the relationship between grammatical aspect (GA) (imperfective vs. past perfect) and accomplishment verbs in event representation in Experiment 1, and then investigated the influence of visual perspective taking on this representation process in Experiment 2. Electroencephalography (EEG) was recorded with slow cortical potentials (SCPs) acting as a measure of cognitive processing during the imagination period, and behavioural measure questionnaires provided ratings of vividness, temporal component, and importance of the imagined events.

It was hypothesized for Experiment 1 that imagining imperfective events would result in more negative SCP amplitudes than when imagining events with past perfect aspect, a finding that would indicate that accomplishments phrased in the imperfective aspect require more cognitive effort to process than those in the past perfect aspect. This prediction is based on the notion that past perfect aspect focuses on the completed nature of an event and accomplishment verbs are verbs with natural end points. As such, there is greater temporal consistency between the semantics of the verb (natural end point) when GA highlights the end of the event. The results of Experiment 1 did show that SCP amplitudes for imperfective accomplishments were more negative than for past perfect accomplishments across the head topographically. Behavioural findings also demonstrated that people more often imagined in the end stage of the events when past perfect aspect was used. Furthermore, imperfective trials were imagined more often in the middle temporal component, which was predicted due to the ongoing nature of the imperfective phrasing.

In Experiment 2, it was hypothesized that imagining accomplishment verbs from a first- person perspective would elicit less negative SCP amplitudes than imagining from a third-person perspective, but with a reduced difference between perspectives seen in previous work as accomplishments contain well-defined endpoints. It was also hypothesized that there would not be differences in amplitudes between first- and third-person perspective as a function of GA. The results of Experiment 2 were, again, similar topographically across the head and showed that the SCP amplitudes of third-person perspective were less negative than first-person perspective. This indicated that it was easier to imagine accomplishments from the third-person perspective. The behavioural measures found that for the imperfective (over past perfect) aspect the vividness of people/entities, objects, and location were all higher. Vividness of people/entities was higher for third-person over first-person perspective, but object vividness was higher from a first- over third-person. It was also seen that events imagined from the first-person perspective were rated as more important than those imagined from the third-person perspective. As in Experiment 1, Experiment 2 found that the middle temporal component was imagined most often for imperfective sentence cues and end temporal component was represented more frequently for past perfect sentence cues. These results extend research on visual perspective taking by providing insight into the behavioural and neural correlates of the interaction between visual perspective and temporal information (semantic and grammatical) associated with verbs.

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