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A Psychophysics Paradigm for the Collection and Analysis of Similarity Judgments
Published on: March 1, 2022
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The P3 indexes the distance between perceived and target image
Carlos de la Torre-Ortiz1, Michiel Spapé2, Tuukka Ruotsalo1,3
1Department of Computer Science, University of Helsinki, Helsinki, Finland.
Psychophysiology
|March 3, 2023
Summary
Generative adversarial networks (GANs) redefine visual similarity by measuring latent space distance. This distance monotonically relates to the P300 brainwave, indicating smooth perceptual identification of complex images.
Area of Science:
- Cognitive Neuroscience
- Computer Vision
- Machine Learning
Background:
- Visual recognition involves comparing perceived objects to mental targets, a challenge with complex stimuli like faces.
- Previous research linked visual similarity to P300 amplitude, but lacked a precise measure for complex stimuli.
- Generative adversarial networks (GANs) offer a novel approach to modeling complex visual relationships.
Purpose of the Study:
- To redefine visual similarity using latent space distances derived from GANs.
- To investigate the relationship between GAN-derived image distances and the P300 brainwave amplitude.
- To explore how GANs can model perception and recognition of complex visual stimuli.
Main Methods:
- Utilized a state-of-the-art generative adversarial network (GAN) to learn a latent space representation of images.
- Conducted a rapid serial visual presentation experiment using oddball images at varying GAN-derived distances from a target.
- Measured P300 amplitude in response to these varying distances to assess perceptual identification.
Main Results:
- A monotonic relationship was found between the GAN-derived distance-to-target and P300 amplitude.
- Perceptual identification was associated with smooth, continuous changes in image similarity.
- P300 sub-components (P3a and P3b) showed distinct but similarly related responses to target distance.
Conclusions:
- The P300 brainwave effectively indexes the distance between perceived and target images in complex visual stimuli.
- GANs provide a powerful new methodology for studying the relationship between stimuli, perception, and recognition.
- This study demonstrates a smooth, drifting similarity measure for complex visual perception.
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