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Updated: Jul 30, 2025

Measurement of Vibration Detection Threshold and Tactile Spatial Acuity in Human Subjects
Published on: September 1, 2016
Pavement cells distinguish touch from letting go
Alexander H Howell1, Carsten Völkner1,2, Patrick McGreevy3
1School of Biological Sciences, Washington State University, Pullman, WA, USA.
Abstract:
A micro-cantilever technique applied to individual leaf epidermis cells of intact Arabidopsis thaliana and Nicotiana tabacum synthesizing genetically encoded calcium indicators (R-GECO1 and GCaMP3) revealed that compressive forces induced local calcium peaks that preceded delayed, slowly moving calcium waves. Releasing the force evoked significantly faster calcium waves. Slow waves were also triggered by increased turgor and fast waves by turgor drops in pressure probe tests. The distinct characteristics of the wave types suggest different underlying mechanisms and an ability of plants to distinguish touch from letting go.
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