# Cognitive Training Improves Disconnected Limbs’ Mental Representation and Peripersonal Space after Spinal Cord Injury

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## Abstract

**:**

## 1. Introduction

## 2. Materials and Methods

#### 2.1. Participants

#### 2.2. Overall Design

#### 2.3. Materials

#### 2.3.1. Questionnaires and Clinical Scales

- The Neurological Level of Injury (NLI), that coincides with the most caudal part of the spinal cord with completely spared sensorimotor functions [13].
- The ASIA Impairment Scale (AIS), that is a 5-point scale concerning the completeness of the lesion [48].
- The Vividness of Motor Imagery Questionnaire-2 (VMIQ—Second Version) [55,56] is a measure of an individual’s capacity to imagine actions. In the present study, it was administered in the version adapted for spinal cord injured people [29] only at T0 with the aim of identifying potential correlations between the patient’s imagery capacity and any effects of the interventions carried out.It assesses three components of motor imagery: (I) visual imagery from a first person perspective (i.e., subjects are asked to visualise their body performing the action as if they were inside their body watching it with their own eyes; (II) visual imagery from a third person perspective (i.e., subjects are asked to visualise their body performing the action as if they were watching themselves from an external position such as in a mirror) or (III) Kinesthetic imagery, KIN (i.e., subjects are asked to simulate the musculo-skeletal sensations generated by executing the actions). These activate partially different processes [57,58,59], with KIN probably being the most sensitive measure of Motor Imagery.

- The Penn Spasms Frequency Scale (PSFS) [49] is used to estimate the intensity and frequency of spasms as reported by the patient.
- The Ashworth Scale-Modified (MAS) [50] is used by clinicians to assess the presence and degree of spasticity on a 5 point scale.
- The Medical Research Council (MRC) scale [51] is used to assess the muscular strength of the right and left legs in movements involving: the flexion, extension and abduction of the hips; the extension of the knee and the dorsal and plantar flexion of the ankle.

#### 2.3.2. Lower Limbs Crossmodal Congruency Task (LLCCT)

#### 2.3.3. Body Sidedness Task (BST)

#### 2.4. Procedure

^{TM}(https://eksobionics.com/, accessed on 8 September 2021)) which was totally automated (i.e., no active muscular activity was required). This was carried out in the rehabilitation rooms of the hospital. The movements were completely passive even though they mimicked a real sequence of steps.

#### 2.5. Data Handling and Statistical Analysis

_{10}) were computed [73,74] by using the package logspline 2.1.15 [75]. Traditionally, with a BF

_{10}> 3 the alternative hypothesis is considered valid, while the null hypothesis is considered valid when there is a BF

_{10}< 1/3 [76]. However, taking into account our small sample size, we decided to use as thresholds BF

_{10}> 5 for the alternative hypothesis, and < 1/5 for the null one, as suggested in [77].

_{eff}) [69] (pp. 286–287) are provided, with the former being a qualitative score that should be around 0.5 if the model represents the data (ppp ≈ 0.5) [78], and the latter being the total number of stationary MCMC iterations, corrected by the autocorrelation among the four MCMCs (n

_{eff}> 10) [69] (pp. 286–287).

_{10}> 5 that describe the behaviour on more than two levels), were computed on the marginal posterior distributions. These marginal posterior distributions come from the summation and subtraction (according to the contrast matrix of the population-level effects) of the posterior distributions of the fixed-effects. For this reason, the marginal posterior distributions were tested by means of a-posteriori distribution percentages [80].

#### 2.5.1. VMIQ-2, PSFS and Clinical Data Analysis

#### 2.5.2. LLCCT Analyses

#### 2.5.3. BST Analyses

## 3. Results

_{eff}> 10, indicating the reliability of the posterior distributions.

#### 3.1. General Imagery Ability—VMIQ-2, PSFS and Clinical Data Results

_{10}= 0.15), Lesion Onset (BF

_{10}= 1.01) and Age (BF

_{10}= 0.22) between the two groups, meaning that they were thus comparable. In the VMIQ-2 analysis, all of the effects showed the validity of the null hypothesis (all BF

_{10}< 0.15), indicating the absence of differences for the three perspectives (1PP, 3PP, Kinesthesic). For this reason, in subsequent analyses in which the VMIQ-2 scores were used as covariates, an average score for each participant for the three perspectives was considered.

_{10}= 0.04 and quadratic BF

_{10}= 0.03), nor were there any effects relating to the interaction between Time and Group (linear BF

_{10}= 0.03 and quadratic BF

_{10}= 0.04). However, a small difference between the “Motor + MI” (1 {1, 1} MRC scale) and “Motor” (1 {1, 3} MRC scale) was observable (BF

_{10}= 134.92).

_{10}≤ 0.34). For this reason, only PSFS scores at T0 were used as covariates in the subsequent analyses.

_{10}= 0.03 and quadratic BF

_{10}= 0.04), Group (BF

_{10}= 0.30) or the interaction between these (linear BF

_{10}= 0.04 and quadratic BF

_{10}= 0.03).

#### 3.2. LLCCT Results

^{2}effects reached BF

_{10}> 5 suggesting the validity of the alternative hypothesis in both cases, namely the differences between Homolateral and Bilateral trials vary between groups and over time.

#### 3.2.1. Covariation with NLI, Lesion Onset, PSFS and VMIQ-2

#### 3.2.2. Ad-Interim Discussion

#### 3.3. BST Results

^{2}, the Group:Time

^{2}and the Background: Group interactions (see Table 4).

#### 3.3.1. Background:Time^{2}

#### 3.3.2. Background:Group

#### 3.3.3. Group:Time^{2}

#### 3.3.4. Covariations with NLI, Lesion Onset, PSFS and VMIQ-2

#### 3.3.5. Ad-Interim Discussion

^{2}interaction). This improvement was evident in the follow-up assessment, suggesting slow neuroplastic processes. Moreover, the recovery of the feet representation was stronger in the “Motor + MI” group (Group:Background interaction) than in the “Motor” group.

## 4. Discussion

#### 4.1. The Effects of Training on PPS

#### 4.2. The Effects of Training on Body Representations

#### 4.3. Pathological Below-Lesion Sensations and Better Clinical Scores Facilitate Body and Peripersonal Space Recovery in MI Training

#### 4.4. Limitations

## 5. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## Appendix A

## Appendix B

## Appendix C

- computing the average of reaction times we are implicitly assuming that they are normally distributed, when they are not [83];
- also when computing the differences between the averages, we do not consider the whole data set, with the consequence that these averages are more prone to outliers and the power of the analysis is thus weaker (1 − β).

If Congruent trials:

μ = Xβ + Zξ with β being the population- and ξ the group-level effects,

If Incongruent trails:

μ = X(β

_{Congruency Effect}+ β

_{Congruent Trials})+ Zξ

_{Congruency Effect}= X(β

_{Incongruent Trial}− β

_{Congruent Trial}) + Zξ,

_{Incongruent}= X(β

_{Congruency Effect}+ β

_{Congruent}) + Zξ,

λ ~ Uniform (0.01, 100),

ξ ~ MultiGaussian (ξ

_{μ}, Ω),

^{−1}(diag(n), n) with n being the number of group-level effects,

ξ

_{μ}~ Gaussian(0, 1000),

## Appendix D

## Appendix E

**Figure A1.**Graphical representation of the marginal posterior distributions of the Space:Condition:Time interaction in the VOID condition. The violin plots represent the marginal posterior distribution of the Bayesian model, the upper and lower boundaries of the box show the limits of the 95% HDI, while the central line represents the distribution mode. On the y−axis, the marginal posterior distribution (P(θ|D)), in milliseconds, represents the performance of the participants, and the x−axis shows the Time points: T0 (pre training), T1 (post training) and T2 (follow-up). (

**A**) = Motor + MI, (

**B**) = Motor. H1 = Pr(x > 0) > 83.5%, meaning that Homolateral > Bilateral, index of PPS representation. H2 = Pr(x > 0) < 16.5%, meaning that Bilateral > Homolateral, and with no PPS representation.

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**Figure 1.**The 4 phases of the study. Evaluations carried out at T0, T1 and T2. NLI = Neurological Level of Injury [13]; AIS = ASIA Impairment Scale [48]; PSFS = Penn Spasms Frequency Scale [49]; MAS = Modified Ashworth Scale [50]; MRC = Medical Council Research scale [51]; VMIQ-2 = modified Vividness of Motor Imagery Questionnaire 2 [29]; BST = Body Sidedness Task [52,53]; LLCCT = Lower Limbs Crossmodal Congruency Task [25,26,54].

**Figure 2.**The Lower Limbs Crossmodal Congruency Task. (

**a**) Position of the participants during the CCE evaluation; (

**b**) Schematic representation of the frontal part of the wooden frame used for the visual stimuli (LEDs) on the inside edge of the foot compartments. The representation of the foot in the image is not in an anatomical position. During the experiment the participants were in front of the wooden frame and the feet were inserted into the compartments.

**Figure 3.**Body Sidedness Task. (

**a**) Incongruent hand stimulus; (

**b**) Congruent hand Stimulus; (

**c**) Incongruent foot stimulus; (

**d**) Congruent foot stimulus; (

**e**) Experimental trial timeline. The last slide “Time up” (in Italian—tempo scaduto) is shown only if the participant did not answer within 1 s.

**Figure 5.**Graphical representation of the marginal posterior distributions of the Space:Condition:Time interaction in the REAL condition. The violin plots represent the marginal posterior distribution of the Bayesian model, the upper and lower boundaries of the box show the limits of the 95% HDI, while the central line represents the distribution mode. On the y−axis, the marginal posterior distribution (P(θ|D)), in milliseconds, represents the performance of the participants, and the x−axis shows the Time points: T0 (pre training), T1 (post training) and T2 (follow-up). (

**A**) = Motor + MI, (

**B**) = Motor. H1 = Pr(x > 0) > 83.5%, meaning that Homolateral > Bilateral, index of PPS representation. H2 = Pr(x > 0) < 16.5%, meaning that Bilateral > Homolateral, and with no PPS representation.

**Figure 6.**Graphical representation of the marginal posterior distributions of the interactions in the Covariation of the LLCCT paradigm in the REAL condition at T1 with NLI, PSFS and VMIQ-2 model. The y axis shows the marginal posterior distribution (P(θ|D)) in milliseconds, representing the performance of the participants. The x-axis refers to the covariates rescaled from z-scores to the original scores. All the graphical representations covariate the performance at the LLCCT task at T1 post-training (greater values on the y-axis represent a better PPS representation) with a different scale. The grey shading represents the 95% CI of the marginal posterior distributions. The x-axis of panels (

**A**,

**B**) shows the scores on the respective scales. The x-axis of the panel (

**C**) shows the Neurological Level of Injury.

**Figure 7.**Graphical representation of the marginal posterior distributions (P(θ|D)) of the Background:Time

^{2}interaction. Description as in Figure 4. H1 = Pr(x > 0) > 83.5%, meaning that the BSE is greater than zero, showing a preserved body representation. T0 = baseline evaluation; T1 = post-training evaluation; T2 = follow-up evaluation.

**Figure 8.**Graphical representation of the marginal posterior distributions (P(θ|D)) of the Background:Group interaction. Description as in Figure 4. H1 = Pr(x > 0) > 83.5%, meaning that the BSE is greater than zero, indicating a preserved body representation. Motor + MI = Motor Treatment and Motor Imagery group. Motor = Motor Treatment only group.

**Figure 9.**Graphical representation of the marginal posterior distributions (P(θ|D)) of the Group:Time interaction. Description as in Figure 4. H1 = Pr(x > 0) > 83.5%, meaning that the BSE is greater than zero, indicating a preserved body representation. H2 = Pr(x > 0) < 16.5%. T0 = baseline evaluation; T1 = post-training evaluation; T2 = follow-up evaluation. Motor + MI = Motor Treatment and Motor Imagery group. Motor = Motor Treatment only group.

**Figure 10.**Graphical representation of the marginal posterior distributions (P(θ|D)) relating to the main effects and interactions in the Covariation of the BSE paradigm with Foot background at T1, with NLI, Lesion Onset PSFS and VMIQ-2 model. Slower values on the y-axis means a better body representation. The description is as in Figure 7. In panels (

**A**,

**B**) the x-axis shows the scores of the respective scales. In panel

**C**the x-axis shows the number of years since the Lesion Onset and the beginning of the training, while in panel

**D**the Neurological Level of injury. Motor + MI = Motor Treatment and Motor Imagery group. Motor = Motor Treatment only group.

ID | Age (Years) ^{a} | Lesion Onset (Years) ^{b} | N. Treat. ^{c} | NLI ^{d} | AIS ^{e} | Group ^{f} | Motor ^{g} | Gender ^{h} |
---|---|---|---|---|---|---|---|---|

Subj01 | 43 | 26.82 | 10 | T4 | A | Motor | EKSO | M |

Subj02 | 37 | 8.83 | 10 | T4 | A | Motor + MI | EKSO | M |

Subj03 | 54 | 30.05 | 10 | L1 | D | Motor | EKSO | M |

Subj04 | 65 | 29.05 | 10 | T6 | A | Motor + MI | EKSO | M |

Subj05 | 44 | 18.24 | 8 | T6 | A | Motor | EKSO | M |

Subj06 | 44 | 28.31 | 8 | T7 | A | Motor | EKSO | M |

Subj07 | 65 | 29.35 | 10 | T4 | A | Motor + MI | EKSO | M |

Subj08 | 57 | 1.63 | 10 | C5 | C | Motor | EKSO | M |

Subj09 | 44 | 27.40 | 8 | T4 | A | Motor + MI | Mobilisation | M |

Subj10 | 65 | 29.54 | 9 | T6 | A | Motor | Mobilisation | M |

Subj11 | 54 | 30.58 | 9 | L1 | D | Motor + MI | Mobilisation | M |

Subj12 | 39 | 5.58 | 9 | T7 | A | Motor | Mobilisation | M |

Subj13 | 44 | 26.58 | 8 | T6 | A | Motor | Mobilisation | F |

Subj14 | 49 | 15.64 | 10 | T4 | A | Motor + MI | Mobilisation | F |

Subj15 | 65 | 10.64 | 10 | T5 | A | Motor + MI | Mobilisation | M |

Mean | 51.22 | 21.22 | 9.33 | T = 12 | A = 12 | Motor = 8 | EKSO = 8 | M = 13 |

St. Dev. | 9.88 | 9.81 | 0.94 | L = 2 | C = 1 | Motor + MI = 7 | Mobilisation = 7 | F = 2 |

C = 1 | D = 2 |

^{a}Age refers to the participants’ ages at the beginning of the training sessions;

^{b}Lesion Onset is the interval between the lesion onset to the beginning of the training sessions (expressed in years);

^{c}N. Treat.—the number of rehabilitation sessions (see Methods section for further details);

^{d}NLI–Neurological Level of Injury, that is the most caudal level of the spinal cord with totally spared somato-sensory functions [13];

^{e}AIS is the ASIA Impairment Scale, A—Complete lesion; C-D—Incomplete lesions with sensory and some motor functions spared below the lesion [48];

^{f}Group indicates whether the subject participated in the Motor or Motor + MI treatment (see Methods section for further details);

^{g}Motor indicates whether motor training of the participant was done by means of exoskeleton (EKSO), or by means of passive mobilisation (Mobilisation, see Methods section for further details);

^{h}M—males; F—females. The rows at the bottom of the table summarise the frequencies of the Thoracic, Lumbar and Cervical lesions, the number of subjects who participated in the group who did only motor treatment or in the group who did motor treatment and motor imagery, and the total number of males (M) and females (F).

**Table 2.**Results for the Bayesian model for the LLCCT evaluations divided into: (A) REAL condition and (B) VOID condition.

(A) REAL Condition | Mode ^{a} | HDI ^{b} | n_{eff} ^{c} | Ȓ ^{d} | BF_{10} ^{e} | ||
---|---|---|---|---|---|---|---|

(Intercept) | 11.065 | 7.238 | 14.390 | 50 | 1.065 | >150 | H1 ^{g} |

Space | 0.902 | −2.510 | 4.101 | 221 | 1.016 | 0.409 | |

Training | −5.116 | −8.177 | −1.961 | 82 | 1.040 | >150 | H1 |

Time | 11.022 | 6.572 | 16.483 | 208 | 1.014 | >150 | H1 |

Time^{2 f} | −15.906 | −22.293 | −11.308 | 135 | 1.019 | >150 | H1 |

Space:Group | 1.051 | −2.027 | 5.046 | 36 | 1.088 | 0.422 | |

Space:Time | 1.285 | −3.052 | 6.456 | 171 | 1.017 | 0.543 | |

Space:Time^{2 f} | 3.766 | −1.567 | 9.287 | 363 | 1.008 | 1.472 | |

Group:Time | −8.082 | −12.878 | −3.068 | 51 | 1.058 | 53.021 | H1 |

Group:Time^{2 f} | −6.824 | −11.620 | −0.643 | 140 | 1.038 | 7.306 | H1 |

Space:Group:Time | −0.748 | −6.254 | 3.970 | 92 | 1.036 | 0.642 | |

Space:Group:Time^{2 f} | −12.339 | −17.981 | −6.478 | 92 | 1.034 | >150 | H1 |

(B) VOID Condition | Mode | HDI | n_{eff} | Ȓ | BF_{10} | ||

(Intercept) | 15.081 | 11.298 | 18.621 | 49 | 1.075 | >150 | H1 |

Space | 6.492 | 3.393 | 9.863 | 69 | 1.045 | >150 | H1 |

Group | 21.305 | 18.552 | 25.146 | 44 | 1.073 | >150 | H1 |

Time | −0.797 | −5.915 | 4.551 | 438 | 1.007 | 0.551 | |

Time^{2 f} | 3.886 | −1.416 | 9.363 | 306 | 1.009 | 1.3 | |

Space:Group | 0.030 | −3.360 | 3.379 | 95 | 1.031 | 0.383 | |

Space:Time | −3.198 | −8.014 | 1.354 | 307 | 1.011 | 1.341 | |

Space:Time^{2 f} | −2.388 | −7.872 | 2.251 | 36 | 1.086 | 0.911 | |

Group:Time | −5.268 | −10.403 | −0.286 | 252 | 1.019 | 4.224 | |

Group:Time^{2 f} | −8.540 | −14.874 | −3.619 | 563 | 1.011 | 28.343 | H1 |

Space:Group:Time | −9.152 | −14.173 | −4.731 | 109 | 1.031 | >150 | H1 |

Space:Group:Time^{2 f} | 6.894 | 2.015 | 11.763 | 208 | 1.014 | 16.964 | H1 |

^{a}Mode refers to the mode of the posterior distribution;

^{b}HDI is the 95% Highest Density Interval [72] (pp. 87–89) of the posterior distribution;

^{c}n

_{eff}—Effective Number of Simulation draws;

^{d}Ȓ—Gelman-Rubin diagnostic index;

^{e}BF

_{10}—Bayes Factor, with the numerator representing the alternative hypothesis and the denominator representing the null hypothesis. The final column indicates whether the BF

_{10}sustains the null (H0) or the alternative (H1) hypothesis;

^{f}Time

^{2}is the quadratic effect of the three timepoints which was necessary to capture non-linear effects. Intercept is the intercept of the Generalised Multilevel Linear Models, Time is the linear effect of the three timepoints (T0, T1, T2);

^{g}H1—alternative hypothesis; H0 = null hypothesis.

**Table 3.**Effects of clinical variables in modulation of PPS around lower limbs. Description as in Table 2.

Mode ^{a} | HDI ^{b} | n_{eff} ^{c} | Ȓ ^{d} | BF_{10} ^{e} | |||
---|---|---|---|---|---|---|---|

(Intercept) | 78.867 | 69.795 | 87.956 | 73 | 1.045 | >150 | H1 |

Group | 2.704 | −7.591 | 10.886 | 190 | 1.016 | 1.11 | |

NLI ^{f} | −0.684 | −8.971 | 9.640 | 52 | 1.059 | 0.911 | |

Lesion Onset | 0.349 | −9.810 | 9.942 | 30 | 1.100 | 1.038 | |

PSFS–Frequency ^{g} | −0.733 | −10.907 | 7.794 | 67 | 1.045 | 1.013 | |

PSFS–Intensity ^{h} | −1.163 | −9.808 | 9.617 | 32 | 1.093 | 1.031 | |

VMIQ2 ^{i} | −0.481 | −11.213 | 9.385 | 151 | 1.022 | 1.035 | |

Group: NLI | 25.995 | 16.680 | 34.995 | 23 | 1.152 | >150 | H1 |

Group: Lesion Onset | −3.457 | −12.678 | 7.139 | 33 | 1.090 | 1.218 | |

Group: PSFS–Frequency | 43.598 | 35.118 | 54.388 | 37 | 1.081 | >150 | H1 |

Group: PSFS–Intensity | 10.226 | −0.297 | 19.338 | 18 | 1.199 | 5.574 | H1 |

Group: VMIQ2 | −4.562 | −14.945 | 5.441 | 17 | 1.204 | 1.552 |

^{a}Mode refers to the mode of the posterior distribution;

^{b}HDI is the 95% Highest Density Interval [72] (pp. 87–89) of the posterior distribution;

^{c}n

_{eff}—Effective Number of Simulation draws;

^{d}Ȓ—Gelman-Rubin diagnostic index.;

^{e}BF

_{10}—Bayes Factor, with the numerator representing the alternative hypothesis and the denominator representing the null hypothesis. The final column indicates whether the BF

_{10}sustains the null (H0) or the alternative (H1) hypothesis;

^{f}NLI—Neurological Level of Injury, that is the most caudal level of the spinal cord with totally spared somato-sensory functions [13];

^{g,h}PSFS—Penn Spasms Frequency Scale [49];

^{i}VMIQ2—Vividness of Motor Imagery Questionnaire 2—version modified in [29].

Mode ^{a} | HDI ^{b} | n_{eff} ^{c} | Ȓ ^{d} | BF_{10} ^{e} | |||
---|---|---|---|---|---|---|---|

Intercept | 3.103 | 1.046 | 4.636 | 9224 | 1.009 | 14.217 | H1 ^{g} |

Background | −0.195 | −1.970 | 1.584 | 123 | 1.022 | 0.179 | H0 ^{g} |

Group | 0.871 | −1.154 | 2.671 | 111 | 1.026 | 0.285 | |

Time | 0.489 | −2.539 | 3.773 | 461 | 1.008 | 0.339 | |

Time^{2 f} | −3.917 | −6.656 | −0.300 | 1498 | 1.003 | 3.509 | |

Background:Group | 3.771 | 1.920 | 5.579 | 1118 | 1.002 | >150 | H1 |

Background:Time | −0.071 | −3.136 | 2.918 | 254 | 1.012 | 0.301 | |

Background:Time^{2 f} | −5.058 | −8.205 | −1.844 | 128 | 1.023 | 40.947 | H1 |

Group:Time | −2.231 | −5.506 | 0.727 | 89 | 1.035 | 0.939 | |

Group:Time^{2 f} | 3.846 | 0.795 | 7.472 | 484 | 1.009 | 6.759 | H1 |

Background:Group:Time | −1.705 | −4.785 | 1.386 | 186 | 1.014 | 0.554 | |

Background:Group:Time^{2 f} | −0.807 | −3.958 | 2.202 | 113 | 1.024 | 0.367 |

^{a}Mode refers to the mode of the posterior distribution;

^{b}HDI is the 95% Highest Density Interval [72] (pp. 87–89) of the posterior distribution;

^{c}n

_{eff}—Effective Number of Simulation draws;

^{d}Ȓ—Gelman-Rubin diagnostic index.;

^{e}BF

_{10}—Bayes Factor, with the numerator representing the alternative hypothesis and the denominator representing the null hypothesis. The final column indicates whether the BF

_{10}sustains the null (H0) or the alternative (H1) hypothesis;

^{f}Time

^{2}is the quadratic effect of the three timepoints which was necessary to capture non-linear effects. Intercept is the intercept of the Generalised Multilevel Linear Models, Time is the linear effect of the three timepoints (T0, T1, T2);

^{g}H1—alternative hypothesis; H0 = null hypothesis.

**Table 5.**Results from the Bayesian model referring to the BSE evaluations with the FOOT background trials at T1, co-varying with NLI, PSFS and VMIQ-2. Description as in Table 2.

Mode ^{a} | HDI ^{b} | n_{eff} ^{c} | Ȓ ^{d} | BF_{10} ^{e} | |||
---|---|---|---|---|---|---|---|

(Intercept) | 58.370 | 50.798 | 66.666 | 227 | 1.015 | >150 | H1 |

Group | 19.090 | 12.301 | 27.211 | 139 | 1.023 | >150 | H1 |

NLI ^{f} | −16.028 | −23.255 | −7.589 | 474 | 1.007 | >150 | H1 |

Lesion Onset | −4.523 | −12.051 | 3.437 | 38 | 1.079 | 1.455 | |

PSFS–Frequency ^{g} | −10.990 | −18.301 | −3.227 | 82 | 1.034 | 31.577 | H1 |

PSFS–Intensity ^{h} | −0.584 | −8.313 | 7.232 | 87 | 1.032 | 0.84 | |

VMIQ2 ^{i} | −2.562 | −10.511 | 4.970 | 70 | 1.040 | 1.009 | |

Group: NLI | 1.654 | −6.306 | 9.293 | 269 | 1.013 | 0.858 | |

Group: Lesion Onset | 7.846 | 0.517 | 16.269 | 39 | 1.077 | 6.497 | H1 |

Group: PSFS–Frequency | 9.857 | 1.792 | 17.298 | 72 | 1.038 | 16.731 | H1 |

Group: PSFS–Intensity | −16.872 | −25.035 | −9.497 | 236 | 1.011 | >150 | H1 |

Group: VMIQ2 | −7.348 | −15.040 | 0.324 | 93 | 1.031 | 4.232 |

^{a}Mode refers to the mode of the posterior distribution;

^{b}HDI is the 95% Highest Density Interval [72] (pp. 87–89) of the posterior distribution;

^{c}n

_{eff}—Effective Number of Simulation draws;

^{d}Ȓ—Gelman-Rubin diagnostic index;

^{e}BF

_{10}—Bayes Factor, with the numerator representing the alternative hypothesis and the denominator representing the null hypothesis. The final column indicates whether the BF

_{10}sustains the null (H0) or the alternative (H1) hypothesis;

^{f}NLI—Neurological Level of Injury, that is the most caudal level of the spinal cord with totally spared somato-sensory functions [13];

^{g,h}PSFS—Penn Spasms Frequency Scale [49];

^{i}VMIQ2–Vividness of Motor Imagery Questionnaire 2—modified version in [29].

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**MDPI and ACS Style**

Moro, V.; Corbella, M.; Ionta, S.; Ferrari, F.; Scandola, M. Cognitive Training Improves Disconnected Limbs’ Mental Representation and Peripersonal Space after Spinal Cord Injury. *Int. J. Environ. Res. Public Health* **2021**, *18*, 9589.
https://doi.org/10.3390/ijerph18189589

**AMA Style**

Moro V, Corbella M, Ionta S, Ferrari F, Scandola M. Cognitive Training Improves Disconnected Limbs’ Mental Representation and Peripersonal Space after Spinal Cord Injury. *International Journal of Environmental Research and Public Health*. 2021; 18(18):9589.
https://doi.org/10.3390/ijerph18189589

**Chicago/Turabian Style**

Moro, Valentina, Michela Corbella, Silvio Ionta, Federico Ferrari, and Michele Scandola. 2021. "Cognitive Training Improves Disconnected Limbs’ Mental Representation and Peripersonal Space after Spinal Cord Injury" *International Journal of Environmental Research and Public Health* 18, no. 18: 9589.
https://doi.org/10.3390/ijerph18189589