Document Type

Thesis

Degree Name

Master of Science (MSc)

Department

Psychology

Program Name/Specialization

Cognitive Neuroscience

Faculty/School

Faculty of Science

First Advisor

Todd R Ferretti

Advisor Role

Associate Professor

Abstract

During the processing of verbs, readers form internal representations of the events described by those verbs. Two key elements in the construction of event representations are temporal information, given by the verbs that describe the represented events, and the visual perspective from which the events are represented. The current study is composed of two experiments aimed at examining the roles these two factors play in event representation. Specifically, the study aimed to determine how temporal information and visual perspective are represented during event imagination.

Experiment 1 investigated the role of temporal information associated with verbs, given by grammatical aspect (GA) and lexical aspect (LA). GA refers to morphosyntactic structures that variably focus on events as being ongoing or as having ended. Experiment 1 was concerned with two past-tense forms of GA: the imperfective (e.g., I was acting), which places focus on the ongoing portion of an event; and the perfective (e.g., I acted), which places focus on the completion of an event. Lexical aspect refers to the property of a verb as possessing or lacking a natural endpoint. Experiment 1 was concerned with accomplishment verbs (e.g., build), which possess natural endpoints, and activity verbs (e.g., act), which lack natural endpoints. Participants read short verb phrases and imagined themselves participating in the described events. During imagination, slow-cortical potential amplitudes (SCPs) were recorded using electroencephalography (EEG), as an index of cognitive effort associated with imagining. Participants also completed behavioural measures on the temporal and sensory properties of their imagined events. SCP results indicated that imagining events based on activity cues was more effortful when cues were given in the perfective than when they were given in the imperfective aspect. In contrast, accomplishments were associated with more effortful imagining when given in the imperfective than when given in the perfective aspect. Differences in GA/LA were also found to lead to changes in the tendency to view events from either the first-person or the third- person perspective, as indicated by self-report measures.

Experiment 2 used cue phrases containing imperfective activity verbs and participants were prompted to either take a first or third person perspective when imagining events. SCP results indicated that greater cognitive effort was associated with imagining activities from the third-person perspective as compared to the first-person perspective.

Results for both experiments are discussed further in terms of topographical differences in SCP negativity and differences in behavioural ratings. This research represents a novel examination of how the imagination process is constrained by the different types of temporal information present in verb cues and the perspective from which imagined events are represented.

Convocation Year

2014

Convocation Season

Fall