Unequal but Fair? Weights in the Serial Integration of Haptic Texture Information

  • Alexandra LezkanEmail author
  • Knut Drewing
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8618)


The sense of touch is characterized by its sequential nature. In texture perception, enhanced spatio-temporal extension of exploration leads to better discrimination performance due to combination of repetitive information. We have previously shown that the gains from additional exploration are smaller than the Maximum Likelihood Estimation (MLE) model of an ideal observer would assume. Here we test if this suboptimal integration can be explained by unequal weighting of information. Participants stroke 2 to 5 times across a virtual grating and judged the ridge period in a 2IFC task. We presented slightly discrepant period information in one of the strokes in the standard grating. Results show linearly decreasing weights of this information with spatio-temporal distance (number of intervening strokes) to the comparison grating. For each exploration extension (number of strokes) the stroke with the highest number of intervening strokes to the comparison was completely disregarded. The results are consistent with the notion that memory limitations are responsible for the unequal weights. This study raises the question if models of optimal integration should include memory decay as an additional source of variance and thus not expect equal weights.


Psychophysics Texture Serial integration 



This work was supported by grants from the Deutsche Forschungsgemeinschaft (GRK 1901/1; TRR 135/1, A05).


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.Justus-Liebig University GiessenGiessenGermany

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