https://doi.org/10.5061/dryad.t4b8gtj9d

In this randomized sham-controlled, double-blind cross-over study, we assessed the effects of Repetitive Somatosensory Stimulation (RSS; known to improve tactile perception through a modulation of primary somatosensory cortex activity) on three mental body representations (MBRs): the body image, the body model and the superficial schema.

With a within-subject design (each subject received RSS and Sham on separate days), three tasks were used to assess these MBRs before and after the RSS or Sham stimulation: the template matching task (TMT; body image), the tactile distance judgement task (TDJT; body model & superficial schema) and the tactile localization task (TLT; superficial schema). Tactile perception was also assessed to check for RSS efficacy through the two-point discrimination task (2PDT).

Description of the data and file structure

2PDT_LMM.xlsx: contains the discrimination thresholds (PSEs) in mm obtained before (Pre) and after (Post) each intervention (Sham / RSS).

2PDT_S1S2.csv: contains the discrimination thresholds (PSEs) in mm obtained in each baseline session S1 and S2 before the intervention (Sham / RSS).

TMT_LMM.xlsx: contains the distortion thresholds (PSEs) in % (of image distortion) obtained before (Pre) and after (Post) each intervention (Sham / RSS).

TDJT_LMM_byTrials.xlsx: contains the perceived distances in mm obtained before (Pre) and after (Post) each intervention (Sham / RSS) in each position (Tip, Base) and distance (15 mm, 30 mm).

TDJT_LMM_byTrials_withoutOutliers.xlsx: same as "TDJT_LMM_byTrials.xlsx" without outliers.

TLT_Vector_LMM.xlsx: contains the constant error magnitude in mm (euclidean distance between the judged and real locations) obtained before (Pre) and after (Post) each intervention (Sham / RSS) in each phalanx (Proximal (P), Middle (M), Distal (D)) and point (Proximal (1), Middle (2), Distal (3)) --> e.g. "Pre P1" refers to the proximal point of the proximal phalanx before the intervention.

TLT_Vector_LMM_withoutOutliers.xlsx: same as "TLT_Vector_LMM.xlsx" without outliers.

TLT_ConstantErrorDirection.csv: contains the constant error direction in degrees (angle between the Judged-Real vector and x-axis) obtained before (Pre) and after (Post) each intervention (Sham / RSS) in each phalanx (Proximal (P), Middle (M), Distal (D)) and point (Proximal (1), Middle (2), Distal (3)).

TLT_CEdirection_HarrisonKanji.xlsx: Same data as in "TLTConstantErrorDirection.csv", arranged for the Harrison-Kanji test (two-way ANOVA for circular data) --> Each sheet contains data for one point. The 1st column contains the direction data (in degrees), the 2nd contains the Intervention (1= Sham; 2= RSS), and the 3rd contains the Session (1= Pre; 2= Post).

TLT_CEdirection_HarrisonKanji.m: this Matlab script reads "TLT_CEdirection_HarrisonKanji.xlsx" and is used to perform the Harrison-Kanji test for each point (P1, P2, P3, M1, M2, M3, D1, D2, D3). --> the output files ("HarrisonKanji_P1.txt" etc.) contain the results of the test. The results consist in either the X² statistic or the F: In the Harrison-Kanji test, when the pooled sample concentration parameter κ>2, the appropriate statistic is the F, while when κ<2, it is the X² (see Harrison & Kanji, 1988 for details).

TLT_Ellipse_LMM.xlsx: contains the variable errors in mm² (the areas of the 95%-confidence ellipses) obtained before (Pre) and after (Post) each intervention (Sham / RSS) in each phalanx (Proximal (P), Middle (M), Distal (D)) and point (Proximal (1), Middle (2), Distal (3)).

TLT_Ellipse_LMM_withoutOutliers.xlsx: same as "TLT_Ellipse_LMM.xlsx" without outliers.

ellipse_generator.m: this Matlab script is used to build the 95%-confidence ellipses and compute their parameters for each subject (at each point in each condition). --> the output file "parameters.xlsx" for each subject displays the parameters for each condition in the following order (from left to right): PreSham, PostSham, PreRSS, PostRSS.

error_ellipse_function.m: this function is called by the "ellipse_generator.m" script and allows to compute the ellipse parameters.

Coordinates.csv: this csv file containing the x and y coordinates (obtained after normalizing the raw coordinates to each subject's finger size) is the input file used by the "ellipse_generator.m" script. Caution: it should be converted back to ".xlsx" to be read by the script.

LMM_2PDT.R: this R script is used to apply Linear mixed-effects models (LMMs) to the 2PDT data.

LMM_TMT.R: this R script is used to apply Linear mixed-effects models (LMMs) to the TMT data.

LMM_TDJT.R: this R script is used to apply Linear mixed-effects models (LMMs) to the TDJT data.

LMM_TLT_Ellipse.R: this R script is used to apply Linear mixed-effects models (LMMs) to the variable error of the TLT data.

LMM_TLT_Vector.R: this R script is used to apply Linear mixed-effects models (LMMs) to the constant error magnitude of the TLT data.

Softwares

The Matlab scripts used to compute the 95%-confidence ellipses parameters (ellipse_generator.m) and to perform the Harrison-Kanji test (TLT_CEdirection_HarrisonKanji.m) were run on Matlab 2021b.

The statistical analyses were run on RStudio (v2024.12.0).

Human subjects data

We received explicit consent from the participants to publish de-identified data in the public domain. In the datasets, numbers were attributed to the participants. They are thus referred to as "Subject number ...".