DOI: 10.7280/d11h49
title: Data from: Tuning of feedforward control enables stable muscle force-length dynamics after loss of autogenic proprioceptive feedback

description: Animals must integrate feedforward, feedback and intrinsic mechanical
 control mechanisms to maintain stable locomotion. Recent studies of guinea
 fowl (Numida meleagris) revealed that the distal leg muscles rapidly
 modulate force and work output to minimize perturbations in uneven
 terrain. Here we probe the role of reflexes in the rapid perturbation
 responses of muscle by studying the effects of proprioceptive loss. We
 induced bilateral loss of autogenic proprioception in the lateral
 gastrocnemius muscle (LG) using self-reinnervation. We compared in vivo
 muscle dynamics and ankle kinematics in birds with reinnervated and intact
 LG. Reinnervated and intact LG exhibit similar steady state mechanical
 function and similar work modulation in response to obstacle encounters.
 Reinnervated LG exhibits 23ms earlier steady-state activation, consistent
 with feedforward tuning of activation phase to compensate for lost
 proprioception. Modulation of activity duration is impaired in rLG,
 confirming the role of reflex feedback in regulating force duration in
 intact muscle.
description: See description in associated paper: doi:10.7554/eLife.53908
description: <b>The file ‘morphologySummaryData.csv’
 contains:</b> Body mass, total gastrocnemius
 muscle mass, lateral gastrocnemius (LG) muscle mass, LG fascicle length
 and LG pennation angle for the ‘intact’ and ‘reinnervated’ cohorts of
 individuals. <b>The file ‘metaDataTable.csv’
 contains:</b> 1) Names of individual data
 files, 2) ‘Treatment’ condition indicating whether the
 individual was from the ‘intact’ cohort (Daley and Biewener 2011) or the
 ‘reinnervated cohort’ (Gordon et al. 2020) 3)
 Individual number:  arbitrary number assigned for individual
 identification in data processing 4) Speed in
 ms-1 5) Terrain condition number: 1 indicates level
 terrain, 5 indicates 5cm obstacle terrain (see methods within papers
 above). 6) Subject body mass in kg
 7) Total gastrocnemius muscle mass 8) Lateral
 gastrocnemius (LG) fascicle length 9) Lateral
 gastrocnemius (LG) pennation angle 10) Recording sample
 frequency   <b>The folders
 ‘Intact’ and ‘Reinnervated’ each contain three files per
 trial:</b>
 <b> ‘<i>fileName</i>.csv’: (File names in
 metaDataTable.csv, above) </b>
 <b>Continuous recordings of muscle data in text format,
 with the following columns:</b> 1) Time: time in seconds relative
 to the original video trigger. 2) muscleLength_mm: fascicle length
 in mm 3)
 muscleLength_FL: fascicle length as a fraction of rest length
 4) velocity_FL:  fascicle
 velocity in lengths per second 5) tendonForceN:  muscle-tendon
 force of gastrocnemius, in Newtons 6) totPower_EMG: total muscle
 electromyographic intensity calculated by summing across wavelet
 frequencies that span the physiological range of frequencies for
 vertebrate skeletal muscle, units mV^2 7) mV_EMG:  raw muscle
 electromyographic signal  
 ‘<b><i>fileName</i> _Cal.mat</b>’: 
 Contains the structure ‘data’ with the continuous recordings, as above,
 ‘params’ with the associated trial metadata, and ‘strideInfo’ with stride
 cycle times. These are provided to allow users to recreate the statistical
 processing and statistics reported in the paper using the Matlab
 scripts.  
 ‘<b><i>fileName</i>
 _StrideTimesWCats.csv</b>’:  Text file containing the data points,
 time (in seconds from video post-trigger’ for identified strides in the
 data file, with the stride category in the 3rd column.  Level strides are
 arbitrarily designated the number ‘10’ in these files, which is changed in
 the Matlab processing scripts to ‘-10’ so that level strides are always
 first in plots and pairwise comparisons.  
 <b>The folder ‘matFiles’ contains the Matlab data
 processing scripts used to generate the main statistical results and
 findings presented in Gordon et al 2020. </b>
 ‘InVivoMuscleProcessingScripts_Intact_v_Reinn.m’ is the main
 script to run the data processing steps and statistical analysis from the
 data contained within the ‘Intact’ and ‘Reinnervated’ folders. See
 comments within.  To run the script, the user must have a valid Matlab
 install,  include the downloaded functions on Matlabs filepaths, and
 update the directory location of the intact and reinnervated data folders
 within this script. Please contact author Monica Daley with any questions
 about these Matlab files. The data spreadsheet,
 'Gordon_etal_Daley_LG_MuscleData.csv' contains the datafile used
 for the statistical results presented in the paper.
 Grouping variables for statistics are found in the first 4
 columns: Individual ID number
 ('ind') Terrain condition
 ('terrain') 1= level,  5 = terrain with repeated 5cm
 obstacles Self-reinnervation treatment
 ('treatment'): 1 = intact,  2 = self-reinnervated
 Stride category ('str_ID') has 5 possible values:  -10
 = level terrain strides, stride prior to an obstacle contact (-1),
 obstacle contact strides (0), stride following obstacle contact (+1), and
 'mid-flat' strides within the level region between obstacles (S
 +2).  The mid-flat strides are grouped together because there is a
 variable number of strides between obstacle encounters.