Visual and haptic illusions in complex stimulus arrays

• Applicant: Privatdozent Dr. Klaus Landwehr
• Subject Area: General, Cognitive and Mathematical Psychology
• Term: from 2012 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 228736743

Visual-illusion figures will be used to inquire into neural mechanisms that underlie the visual and visually mediated haptic perception of geometrical features of dot and line arrange-ments. Adult human observers will be asked to discriminate the lengths of pairs of lines or the sizes of empty spatial intervals in ordinal terms (larger, smaller, etc.). Performance will be analyzed by fitting psychometric functions from which difference thresholds, which charac-terize observers’ sensitivity, and response biases, which quantify amounts of error, can be read off. Stimulus features will include the figures’ overall orientation, the relative tilt of parts of the figures, the connectivity, collinearity and parallelism of these parts, and the whole figures’ symmetry. Findings will be interpreted as evidence for neural interactions or effects of higher-order schematic processing.

• DFG Programme: Research Grants