Page 59 - It' about time: Studying the Encoding of Duration
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                                Chapter 3  the DAE, encoding of the unattended duration was either too sparse or too weak to lead to a measurable DAE. In other words, while we do not argue for the absolute lack of a representation of the unattended duration per se, we do argue that any information encoded about the unattended stimulus will not lead to a robust, stable representation, and as such will not impact the perception and behavior of the observer. Our results demonstrate that attention gates the encoding of duration: attended durations lead to a DAE, while unattended durations do not. These findings are in line with earlier work suggesting attentional limits on the processing of duration and support the idea that duration encoding is an effortful process that requires gating by visual attention. We conclude that visual attention underlies the selection of relevant temporal information when multiple sources are present. Methods Participants Data were collected from 12 participants (2 male, age M = 28, SD = 8.41) in Experiment 1, and 20 participants (7 male, age M = 25.55, SD = 7.72) in Experiment 2. All participants had normal or corrected-to-normal vision, and did not suffer from any neurological disorders. All participants were informed of their rights and gave written informed consent before the experiment started. Both experiments were approved by the local ethics committee of the Faculty of Social and Behavioral Sciences of Utrecht University and conducted in accordance with the guidelines expressed in the Declaration of Helsinki. Apparatus and stimuli The same materials were used for both experiments. All visual stimuli were presented on a linearized Electron 22BlueIII CRT monitor (1280 x 1024, 100Hz), controlled by a Dell OptiPlex 7040 workstation (Windows 10) using Matlab 2015b. For Experiment 1, gaze position measurements were taken using the EYE TRIBE tracker, sampling at 30 Hz. This eye tracker was controlled using the PyGaze software package and eye tribe toolbox for Matlab (Dalmaijer, 2014; Dalmaijer et al., 2014). Furthermore, a chin- and headrest were used to increase head stability during tracking. Auditory stimuli consisted of a burst of white noise (60 dB, 0.01 ms ramp) presented through a Sennheiser on-ear headset. 58 


































































































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