Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.707348
Title: Investigating the mechanisms underlying subsecond visual event timing
Author: Latimer, Kevin
ISNI:       0000 0004 6061 6907
Awarding Body: Queen's University Belfast
Current Institution: Queen's University Belfast
Date of Award: 2016
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Abstract:
At present the nature and location of the mechanisms involved in encoding subsecond durations is unclear. The experiments outlined within this thesis aimed to provide some insights into these mechanisms by exploiting a phenomenon known as the ‘duration compression effect’, i.e. instances where adapting to a stimulus results in the duration of a subsequently presented, short-lasting stimulus being underestimated. By selecting stimuli known to activate specific neural areas it is possible to infer if these areas are involved in subsecond duration encoding based on whether or not the stimuli produce a duration compression effect. The first set of experiments (Chapter 4) aimed to investigate the direction-tuning of the duration compression effect, based on the previous evidence that the effect is direction-contingent at certain speeds (Curran & Benton, 2012; Bruno et al., 2013). The second set of experiments aimed to determine the possible roles of local and global motion processing mechanisms in timing subsecond events. The final set of experiments investigated the frame of reference within which visual timing mechanisms operate. These experiments resulted in several key findings. Firstly, they confirm that the duration compression effect is direction-tuned and they also provide evidence that the effect remains direction-tuned at higher speeds. This points to the involvement of cortical mechanisms in subsecond timing, due to cortical area V1 being regarded as the earliest part of the visual pathway to contain direction-contingent neurons. The experiments also provide some evidence to suggest the existence of timing mechanisms at the level of global motion processing. Finally, the experiments demonstrate that both retinotopic and spatiotopic mechanisms play a role in timing subsecond events. The overall conclusion based on the results complements results of previous studies (Curran & Benton, 2012; Bruno et al., 2013) and suggests that subsecond visual timing mechanisms are distributed throughout various regions of the visual processing pathway.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.707348  DOI: Not available
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