How low can you go?: Spatial frequency sensitivity in pure alexia

Randi Starrfelt; Simon Nielsen; Thomas Habekost; Tobias S. Andersen

doi:10.1016/j.bandl.2013.05.006

How low can you go? Spatial frequency sensitivity in pure alexia

Randi Starrfelt, Simon Nielsen, Thomas Habekost, Tobias S. Andersen

14 Citationer (Scopus)

2074 Downloads (Pure)

Abstract

Pure alexia is a selective deficit in reading, following lesions to the posterior left hemisphere. Writing and other language functions remain intact in these patients. Whether pure alexia is caused by a primary problem in visual perception is highly debated. A recent hypothesis suggests that a low level deficit - reduced sensitivity to particular spatial frequencies – is the underlying cause. We tested this hypothesis in a pure alexic patient (LK), using a sensitive psychophysical paradigm to examine her performance with simple patterns of different spatial frequency. We find that both in a detection and a classification task, LK’s contrast sensitivity is comparable to normal controls for all spatial frequencies. Thus, reduced spatial frequency sensitivity does not constitute a general explanation for pure alexia, suggesting that the core deficit in this disorder is at a higher level in the visual processing stream.

Originalsprog	Engelsk
Tidsskrift	Brain and Language
Vol/bind	126
Udgave nummer	2
Sider (fra-til)	188-192
Antal sider	5
ISSN	0093-934X
DOI	https://doi.org/10.1016/j.bandl.2013.05.006
Status	Udgivet - aug. 2013

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10.1016/j.bandl.2013.05.006

Starrfelt et al Spatial frequency B L 2013Accepteret manuskript, 757 KB

Citationsformater

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AU - Nielsen, Simon

AU - Habekost, Thomas

AU - Andersen, Tobias S.

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