Visual hallucinations are prevalent, potentially disabling symptoms of Parkinson's Disease. Multiple impairments in bottom-up sensory processing and top-down perceptual modulation are implicated in the pathophysiology of these phenomena. In healthy individuals, visual illusions are elicited by illusory figures through parametric manipulations of geometrical configurations, contrast, color, or spatial relationships between stimuli.
View Article and Find Full Text PDFAtten Percept Psychophys
January 2024
The Spatial-Numerical Association of Response Codes (SNARC) effect is evidence of an association between number magnitude and response position, with faster left-key responses to small numbers and faster right-key responses to large numbers. Similarly, recent studies revealed a SNARC-like effect for tempo, defined as the speed of an auditory sequence, with faster left-key responses to slow tempo and faster right-key responses to fast tempo. In order to address some methodological issues of previous studies, in the present study we designed an experiment to investigate the occurrence of a SNARC-like effect for tempo, employing a novel procedure in which only two auditory beats in sequence with a very short interstimulus interval were used.
View Article and Find Full Text PDFThe Spatial-Numerical Association of Response Codes (SNARC) effect consists in faster left-/right-key responses to small/large numbers. (Bächtold et al., Neuropsychologia 36:731-735, 1998) reported the reversal of this effect after eliciting the context of a clockface-where small numbers are represented on the right and large numbers on the left.
View Article and Find Full Text PDFThe Spatial-TEmporal Association of Response Codes (STEARC) effect (Ishihara et al. in Cortex 44:454-461, 2008) is evidence that time is spatially coded along the horizontal axis. It consists in faster left-hand responses to early onset timing and faster right-hand responses to late onset timing.
View Article and Find Full Text PDFJ Exp Psychol Hum Percept Perform
October 2021
Previous literature on the spatial-numerical association of response codes (SNARC) effect examined which factors modulate spatial-numerical associations. Recently, the role of order in the SNARC effect has been debated, and further research is necessary to better understand its contribution. The present study investigated how the order elicited by the context of the stimuli and by task demands interact.
View Article and Find Full Text PDFIn a recent paper by Casasanto and Pitt (2019), the authors addressed a debate regarding the role of order and magnitude in SNARC and SNARC-like effects. Their position is that all these effects can be explained by order, while magnitude could only account for a subset of evidence. Although we agree that order can probably explain the majority of these effects, in this commentary we argue that magnitude is still relevant, since there is evidence that cannot be explained based on ordinality alone.
View Article and Find Full Text PDFUniversity students are the most employed category of participants in cognitive research. However, researchers cannot fully control what their participants do the night before the experiments (e.g.
View Article and Find Full Text PDFThe verbal descriptions of an environment elicit a spatial mental model, in which the linear disposition of the described objects might be related to the properties of the description. In particular the direction from which the environment is encoded might shape the spatial mental model, as a consequence of a cultural bias in reading and writing direction. The aim of the present study was to examine the influence of the direction in which objects are encoded on the retrieval of spatial information.
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