Pattern Separation and Related Cognitive Functions in Combat and Contact Sports Athletes: Working Memory, Attention, and Processing Speed

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

General Comments:

While this study addresses an important topic and aims to fill a clear gap in the literature regarding RHIs and memory functioning, the overall presentation is somewhat confusing. The core objectives and justifications remain unclear.

 

Specific Comments:

Justification for pattern separation: The authors need to clarify why pattern separation was selected as the primary index for cognitive function. Since the main objective is to examine the effects of RHIs on memory functioning, the choice of this specific task over standard memory tests is not sufficiently justified. Please provide a more robust rationale.

Novelty and significance: The baseline rationale for this study is weak. The existing literature heavily documents that concussions lead to cognitive and memory impairments (e.g., verbal memory and delayed recall) in retired athletes. The authors should clearly explain what new insights this study provides and why investigating RHIs specifically on pattern separation is critical to the field.

Mismatch between hypothesis and study aim: The proposed hypothesis does not align with the stated aim of the study. The authors state, “We hypothesized that athletes involved in combat sports would show the greatest impairment in episodic memory performance...” However, the primary aim of this study was to examine the overall effects of RHIs on cognitive function (L99-L101 “Following this line of reasoning, the present study aims to examine the effects of RHIs on memory functioning, with a specific focus 100 on pattern separation.”). It is unclear whether the authors intended to investigate how different types of sports affect cognition. If comparing sport types was a main objective, the Introduction should clearly establish the rationale for this comparison. In its current form, the shifting focus between the general effects of RHIs and sport-specific differences obscures the primary purpose of the study.

Inadequacy of results and lack of RHI quantification: The Results section does not adequately address the core research question. While the purpose of this study is to examine the effects of RHIs on memory, the authors compare cognitive performance across different sport groups (e.g., combat sports vs. rugby) without quantifying the actual level or cumulative history of RHIs for individual athletes. RHI exposure can vary significantly even among athletes in the same sport. Therefore, the authors should directly assess the level of RHI exposure and its specific influence on cognition, independent of the sport type. If examining sport-specific differences is a secondary aim (e.g., evaluating whether the effect of RHIs on cognition is moderated by the type of sport), this must be explicitly stated. Currently, the lack of quantified RHI data renders the discussion regarding sport-specific differences highly speculative. The authors need to revise the Introduction, Results, and Discussion to ensure a cohesive and well-justified narrative for both objectives.

Author Response

Manuscript ID: applsci-4376911

Title (submitted): Exploring Pattern Separation and Cognitive Functions in Combat and Contact

Sports Athletes

Journal: Applied Sciences (MDPI)

Reviewer 1

General comment. While this study addresses an important topic and aims to fill a clear gap in the

literature, the overall presentation is somewhat confusing and the core objectives and justifications

remain unclear.

Response: We have restructured the framing to make the objectives explicit. The Introduction now

states two clearly separated aims: (1) a primary aim, namely to examine pattern separation and

related cognitive functions in athletes exposed to RHIs compared with non-exposed controls; and

(2) a secondary, exploratory aim, namely to compare sport groups with contrasting impact profiles

(combat sports versus rugby). Because exposure was not quantified with a common objective metric

across sports, these between-sport comparisons are labelled as exploratory throughout. We have

also strengthened the rationale for pattern separation and the statement of novelty, as detailed

below.

Change from the submitted version: The submitted Introduction stated a single aim (“the present study

aims to examine the effects of RHIs on memory functioning, with a specific focus on pattern separation”).

The revised Introduction states two explicit aims, a primary aim and a secondary, exploratory one.

Location in the revised manuscript: Introduction, the sentence beginning “The present study therefore

had two aims.”

Comment 1 (Justification for pattern separation). The authors need to clarify why pattern

separation was selected; the choice of this specific task over standard memory tests is not sufficiently

justified.

Response: We have made the rationale explicit in the Introduction. We now state that pattern

separation is a memory process associated with hippocampal (dentate gyrus) function, that the

dentate gyrus is reported to be vulnerable to mechanical stress, and that, unlike traditional

recognition measures, which can be supported by familiarity-based processes, pattern separation

requires the discrimination of highly similar stimuli and may therefore be more sensitive to subtle

memory alterations that conventional recognition tasks can miss. The MST is thus presented as a

complement to, not a replacement for, standard memory measures.

Change from the submitted version: The submitted version justified the MST only briefly. The revised

Introduction adds an explicit rationale for selecting pattern separation over standard recognition measures.

Location in the revised manuscript: Introduction (Section 1), the paragraph introducing the Mnemonic

Similarity Task and the sensitivity of pattern separation to subtle hippocampal dysfunction.

Comment 2 (Novelty and significance). The existing literature heavily documents that concussions

lead to cognitive and memory impairments in retired athletes; the authors should clearly explain what

new insights this study provides.

Response: We have clarified the contribution at the end of the Introduction. We now note that,

although a growing body of research has examined memory in athletes exposed to RHIs, no previous

study has specifically investigated pattern separation in athletes participating in combat and contact

sports characterized by different exposure profiles. The present study therefore extends prior work,

which has focused mainly on verbal memory and delayed recall in retired, concussion-exposed

athletes, to high-resolution memory discrimination in active athletes whose exposure is

predominantly subconcussive.

Change from the submitted version: The submitted version stated only that “this is the first study to

specifically address this aspect of memory functioning”. The revised version adds an explicit statement of

novelty (“no previous study has specifically investigated pattern separation” in these athletes) and

contrasts it with prior work on verbal memory and delayed recall.

Location in the revised manuscript: Introduction, the sentence containing “no previous study has

specifically investigated pattern separation” in these athletes.

Comment 3 (Mismatch between hypothesis and aim). The proposed hypothesis (combat-sport

athletes showing the greatest impairment) does not align with the stated aim (examining the overall

effects of RHIs on memory).

Response: We have realigned aim and hypothesis. The two aims are now stated explicitly, and the

hypothesis is phrased to match them: we hypothesized that fighters would show the lowest

performance in pattern separation and related measures, followed by rugby players, with controls

performing best. The between-sport comparison is consistently framed as the secondary,

exploratory aim.

Change from the submitted version: Submitted hypothesis: “athletes involved in combat sports would

show the greatest impairment in episodic memory performance”. Revised hypothesis: “we hypothesized

that fighters would show the lowest performance”, now aligned with the two stated aims.

Location in the revised manuscript: Introduction, the sentence beginning “Based on the differing nature

and frequency of head impacts … we hypothesized that fighters would show the lowest performance.”

Comment 4 (Inadequacy of results and lack of RHI quantification). The authors compare

cognitive performance across sport groups without quantifying the actual level or cumulative history

of RHIs for individual athletes; if the sport-specific comparison is a secondary aim, this must be

explicitly stated.

Response: We agree, and this point overlaps with Reviewer 2 (Major issue 1). We have taken three

steps. First, the self-reported exposure variables that were collected are reported in full (Tables 1

and 2). Second, as an exploratory analysis of exposure independent of sport category, we added,

within the fighter group (N = 26), Spearman rank correlations between the number of fights and the

primary outcomes (LDI, N-back2, N-back3), with FDR correction; after correction, none of these

correlations reached significance (all q ≥ .39). Third, the between-sport comparison is now explicitly

framed as a secondary, exploratory aim. Where objective quantification was not possible, we state

this transparently in the revised Limitations and, per check-list point (V), here.

Change from the submitted version: The submitted version contained no exposure-based analysis

independent of sport type. The revised version adds an exploratory within-fighter correlation analysis (new

Table 5) and an expanded Limitations on exposure quantification.

Location in the revised manuscript: Results, the Spearman correlations within the fighter group (Table

5); and the Limitations (the paragraph on exposure not being captured by a common objective metric).

We believe these revisions clarify the objectives, moderate the interpretation in keeping with the

cross-sectional design, correct the reporting errors, clarify the scoring of the cognitive measures,

and address exposure more directly through the added analyses. We thank the reviewers and the

Editor again for their time and for comments that have improved the manuscript.

On behalf of all authors,

Alessandro Santirocchi

Reviewer 2 Report

Comments and Suggestions for Authors

Thank you for the opportunity to review this manuscript. The topic is interesting, novel, and relevant, particularly in relation to cognitive functioning and repetitive head impacts in combat and contact sports. More detailed comments and suggested revisions are provided in the review comments.

Comments for author File: Comments.pdf

Author Response

Manuscript ID: applsci-4376911

Title (submitted): Exploring Pattern Separation and Cognitive Functions in Combat and Contact

Sports Athletes

Journal: Applied Sciences (MDPI)

Reviewer 2

Overall assessment. The topic is interesting and the three-group design is a clear strength, but the

manuscript requires major revision, mainly regarding exposure characterization, causal

interpretation in a cross-sectional design, incomplete statistical reporting, a possible effect-size error,

unclear scoring of several cognitive measures, and figure/table presentation.

Response: We thank the reviewer for the balanced and detailed assessment, and we have

addressed each major and section-specific point below, with the change relative to the submitted

version and the location in the revised manuscript indicated in each case.

Major issues

Major issue 1 (Exposure characterization). The manuscript should report years of participation,

sparring sessions, time since last bout/match, time since last concussion, and recent head impacts;

the distinction between fighters and rugby players remains insufficiently quantified.

Response: We agree. The exposure information that was available is now reported, and we have

substantially expanded the Limitations to state, openly, that RHI exposure was not quantified with

an objective, individual-level metric common to all groups, that the self-report proxies are incomplete

and not directly comparable across sports, and that finer-grained indices (years at the professional

level, number of sparring sessions, time since the last bout or match, time since the last diagnosed

concussion, and head impacts in the days before testing) were not collected and could not be

reconstructed. Per check-list point (V), we acknowledge this rather than estimate it post hoc.

Change from the submitted version: The submitted Limitations did not itemise the missing exposure

indices. The revised Limitations list them explicitly and state that exposure was not captured through a

common objective metric.

Location in the revised manuscript: Limitations, the sentences on exposure not being captured by a

common objective index; and Section 2.1 / Tables 1 and 2 for the available exposure variables.

Major issue 2 (Cross-sectional design and causal language). Phrases such as “effects of RHIs”

should be softened to association-based wording, especially in the Abstract and Discussion.

Response: Agreed. We have revised the causal wording throughout. In the Abstract, the previous

“graded effect of RHIs” now reads as a graded pattern of performance across groups. In the

Discussion, several formulations have been softened: the discussion of accumulated exposure now

notes that whether group differences emerge only after prolonged participation cannot be determined

from the cross-sectional design; “which may cumulatively lead to microstructural brain changes” now

reads “which have been associated with”; and “may result in cognitive outcomes” now reads “may

be accompanied by different patterns of cognitive performance”.

Change from the submitted version: Abstract: “a graded effect of RHIs” became “a graded pattern of

performance across groups”. In the Discussion, causal verbs (“effects of RHIs”, “lead to”, “result in”) were

replaced with associative wording (“associated with”, “accompanied by”).

Location in the revised manuscript: Abstract, the sentence with “a graded pattern of performance across

groups”; and the Discussion, the sentences beginning “Our findings are in line with Stewart et al.”, “In

combat sports, athletes are exposed to frequent RHIs”, and “These distinct exposure profiles”.

Major issue 3 (Heterogeneous, not fully comparable groups). The fighter group combines

Boxing, MMA, and Muay Thai, and the rugby group uses a different exposure metric; provide

subgroup/exposure analyses or frame the comparisons as exploratory.

Response: We acknowledge both the heterogeneity of the fighter group and the different exposure

metric used for rugby. Because the sample size within each discipline was limited, subgroup

analyses were not conducted, and we now state that the findings should be interpreted at the level

of the broader combat-sport category rather than as evidence of sport-specific differences. The

between-sport comparison is presented as exploratory, and the within-group exposure analysis is

reported in Table 5.

Change from the submitted version: The submitted version noted the heterogeneity only as a limitation.

The revised version adds an explicit instruction to interpret the findings at the level of the broader combatsport

category and frames the between-sport comparison as exploratory.

Location in the revised manuscript: Discussion, the sentence beginning “Therefore, the present findings

should be interpreted at the level of the broader combat-sport category”; and the corresponding sentence

in the Limitations.

Major issue 4 (Scoring of cognitive measures). Table 3 values do not appear to be standard

WAIS-IV raw or scaled scores, although the Methods state raw scores were used. Clarify how each

score was computed.

Response: We apologise for the inconsistency. The reference to "raw scores" was imprecise. For

the WAIS-IV subtests (Digit Span forward and backward, Coding) and the Attentional Matrices, the

reported values are raw scores rescaled to a 0–1 range through a monotone linear rescaling,

normalising each raw score to the maximum value observed in the sample for that measure. The Nback

tasks were scored as proportions of correct responses (accuracy scores ranging from 0 to 1).

The two MST indices, LDI and REC, are computed differently (as bias-corrected difference scores)

and are defined in Section 2.2; we have therefore kept them distinct from the other measures. The

note to Table 3 and the legend of Figure 1 have been aligned accordingly.

Change from the submitted version: The submitted Table 3 note and Methods stated that “raw scores

are reported”. The revised version clarifies the scoring of each measure: raw scores from the WAIS-IV

subtests and the Attentional Matrices were normalised to the sample maximum (rescaled to a 0–1 range)

and the N-back tasks were scored as proportions of correct responses (accuracy scores),

Location in the revised manuscript: Section 2.3 (Cognitive Measures), the sentence beginning “Since

the cognitive tasks were scored on heterogeneous scales, raw scores from the WAIS-IV subtests”; the

note to Table 3; and the legend of Figure 1.

Major issue 5 (Statistical analysis and multiple-comparison strategy). Specify which outcomes

used parametric ANCOVA and which used permutation ANCOVA, report assumption checks, and

clarify the level at which correction was applied.

Response: We have clarified the Statistical Analyses section. We now report that ANCOVA

assumptions were examined for each outcome, and that permutation-based ANCOVAs (R package

coin) were used for the outcomes that violated the homogeneity-of-variance assumption, namely

Digit Span backward, N-back3, and REC, whereas parametric ANCOVAs were used for all remaining

outcomes. We also state that the FDR (Benjamini-Hochberg) correction was applied across the posthoc

pairwise comparisons following each significant omnibus test.

Change from the submitted version: The submitted version stated that permutation ANCOVAs were

used “when the assumption of normality was violated”, without specifying which outcomes. The revised

version names the permutation outcomes (Digit Span backward, N-back3, REC) and reports the

assumption check.

Location in the revised manuscript: Section 2.5 (Statistical Analyses), the sentence specifying

permutation-based ANCOVAs for “Digit Span backward, N-back3, and REC” and the FDR correction.

Major issue 6 (Effect-size reporting error). For reaction time to old images, F(2,67) = 3.04, p =

.055, ηpÇ = 0.83 is implausible; it is likely .083.

Response: Thank you for catching this. The value was a typographical error and now reads ηpÇ =

0.083. We re-checked all reported effect sizes for internal consistency with their F values and

degrees of freedom, and found no further discrepancies.

Change from the submitted version: Submitted: “ηÇp = 0.83”. Revised: “ηpÇ = 0.083”.

Location in the revised manuscript: Results, the MST reaction-time analysis, the value “ηpÇ = 0.083”.

Major issue 7 (Hippocampal/dentate-gyrus interpretation). Since no neuroimaging or biomarkers

were included, statements implying dentate-gyrus or hippocampal alteration should be framed as

theoretical interpretation.

Response: We agree. Pattern separation is now described as a memory process associated with

hippocampal function, and statements concerning dentate gyrus or hippocampal involvement are

framed as theoretical interpretation (for example, the “proposed sensitivity” of hippocampally-linked

pattern separation). We reiterate, in the Abstract and Discussion, that the present findings are

behavioural and that neuroimaging or biomarker evidence would be required for confirmation.

Change from the submitted version: The submitted version described pattern separation as “a

hippocampal-dependent cognitive function”. The revised version describes it as “a memory process

associated with hippocampal function” and frames dentate-gyrus involvement as interpretation.

Location in the revised manuscript: Abstract, “a memory process associated with hippocampal

function”; and the Discussion, the sentence containing “the proposed sensitivity of hippocampally-linked

pattern separation”.

Section-specific comments

Title, abstract and keywords. The title is clear, but “cognitive functions” is broad; consider

specifying the domains. The Abstract causal wording should be softened.

Response: The Abstract wording has been softened in line with Major issue 2. Following the

reviewer’s suggestion, we have also revised the title to specify the cognitive domains assessed.

Change from the submitted version: Submitted title: “Exploring Pattern Separation and Cognitive

Functions in Combat and Contact Sports Athletes”. Revised title: “Pattern Separation and Related

Cognitive Functions in Combat and Contact Sports Athletes: Working Memory, Attention, and Processing

Speed”.

Location in the revised manuscript: The title of the manuscript.

Introduction (terminology and HRIs typo). Correct the inconsistent use of “HRIs”, which should

be “RHIs” throughout.

Response: All occurrences of “HRIs” have been corrected to “RHIs”, and we have checked

terminology consistency throughout the manuscript.

Change from the submitted version: The submitted version contained the inconsistent abbreviation

“HRIs”. In the revised version the term no longer appears; “RHIs” is used consistently.

Location in the revised manuscript: Throughout the manuscript; the term “HRIs” no longer appears.

Materials and Methods (participant description and male-only sample). The controls are

described both as professional athletes and as recreationally active; this must be corrected. The

male-only design should be acknowledged.

Response: Thank you. The participant description has been corrected so that professional, clubaffiliated

status is attributed to the fighter and rugby groups only, while the control group is described

unambiguously as recreationally active and non-competitive. We have also added, in the Limitations,

an explicit statement that only male participants were included, so the generalizability to female

athletes remains uncertain.

Change from the submitted version: The submitted version described all participants as “all playing at

a professional level and affiliated with clubs”, contradicting the later description of the controls. The revised

version describes the controls as “recreationally active, non-competitive” and adds the male-only limitation.

Location in the revised manuscript: Section 2.1 (Participant), the sentence on the control group as

recreationally active and non-competitive; and the Limitations, “only male participants were included”.

Materials and Methods (MST reaction-time cleaning). Report whether reaction times were

cleaned for outliers, extreme values, or anticipatory/invalid responses.

Response: We have clarified this in the Methods. Reaction times in the MST were analysed only for

correct responses, and no additional outlier-removal or trimming procedure (for example, for

anticipatory or extreme values) was applied; all correct-response trials were retained in the analyses.

Change from the submitted version: The submitted version did not report any reaction-time handling

procedure. The revised Methods state explicitly that no trimming was applied and that all correct-response

trials were retained.

Location in the revised manuscript: Section 2.2 (Pattern Separation Task), the sentence beginning

“Reaction times in the MST were analysed only for correct responses.”

Materials and Methods (procedure / exclusion vs descriptive). Clarify whether recent training,

sparring, match participation, or concussion symptoms were exclusion criteria or only recorded

descriptively.

Response: We have clarified this in the Procedure. Recent training, sparring, and match

participation were recorded descriptively and were not used as exclusion criteria, with the exception

of the clinical exclusion criteria already listed. We also note, in the Limitations, that recent sparring

could not be fully controlled and may have influenced fighters’ performance.

Change from the submitted version: The submitted Procedure did not state whether recent training or

sparring were exclusion criteria. The revised Procedure states they were recorded descriptively and were

not used as exclusion criteria.

Location in the revised manuscript: Section 2.4 (Procedure), the sentence stating that recent training

or sparring and match participation “were recorded descriptively but were not used as exclusion criteria.”

Materials and Methods (power analysis). The power analysis appears to be sensitivity/achievedpower

reasoning; the claim of being “adequately powered” should be softened.

Response: Agreed. We have reframed the analysis as a sensitivity power analysis based on the

sample actually collected, and we no longer claim the study was “adequately powered”. The revised

text now reports the minimum effect size detectable with N = 72 at α = .05 and 80% power (f ≈ 0.37,

ηÇ ≈ 0.12) and notes that this is smaller than the large memory effects reported in the reference study

[35] (ηÇp ≈ 0.19–0.24); the present sample therefore provided sufficient sensitivity to detect effects

of comparable magnitude.

Change from the submitted version: The submitted version concluded that the study was 'adequately

powered'. The revised version reframes the analysis as a sensitivity analysis (minimum detectable effect)

and softens the claim accordingly.

Location in the revised manuscript: Section 2.5 (Statistical Analyses), the sentence containing

“sensitivity to detect effects comparable in magnitude to those reported in the reference study.”

Statistical analysis (estimated marginal means and confidence intervals). Report estimated

marginal means rather than only raw descriptive means, and add confidence intervals for the key

group differences.

Response: We have added estimated marginal means adjusted for age and education, with 95%

confidence intervals, for the primary outcomes (LDI, N-back2, N-back3), now reported in Table 4,

together with 95% confidence intervals for the adjusted pairwise differences. For LDI, the adjusted

differences were Control versus Fighting +0.31 [0.20, 0.42], Control versus Rugby +0.15 [0.03, 0.28],

and Fighting versus Rugby -0.15 [-0.27, -0.03]; for N-back2, Control versus Fighting +0.13 [0.02,

0.24] and Fighting versus Rugby -0.18 [-0.30, -0.07]; and for N-back3, Control versus Fighting +0.19

[0.07, 0.31] and Fighting versus Rugby -0.21 [-0.34, -0.08]. The adjusted means are virtually identical

to the raw descriptive means, confirming that the group differences are robust to the covariate

adjustment.

Change from the submitted version: The submitted version reported only raw descriptive means (Table

3). The revised version adds estimated marginal means with 95% confidence intervals and adjusted

pairwise differences (new Table 4).

Location in the revised manuscript: Section 2.5 / Results, the estimated marginal means and adjusted

pairwise differences with 95% confidence intervals (Table 4).

We believe these revisions clarify the objectives, moderate the interpretation in keeping with the

cross-sectional design, correct the reporting errors, clarify the scoring of the cognitive measures,

and address exposure more directly through the added analyses. We thank the reviewers and the

Editor again for their time and for comments that have improved the manuscript.

On behalf of all authors,

Alessandro Santirocchi

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

No Further comments.

Author Response

Manuscript ID: applsci-4376911 - Revision SUBMITTED

Manuscript: “Pattern Separation and Related Cognitive Functions in Combat and Contact Sports Athletes: Working Memory, Attention, and Processing Speed” (Applied Sciences)

We thank both reviewers for their evaluation of the revised manuscript. We are grateful to Reviewer 1 for indicating no further comments, and to Reviewer 2 for the positive assessment and the additional clarifying suggestions. Below we respond to each of the remaining points. All changes introduced in this round are shown as tracked changes in the revised manuscript.

Reviewer 1

We thank the reviewer for the time and effort devoted to the manuscript across both rounds of review, and for recommending the manuscript without further comments. No changes were required.

Reviewer 2 Report

Comments and Suggestions for Authors

Thank you for the detailed and constructive response to my comments. The authors have addressed the major methodological and reporting concerns in a satisfactory manner. I recommend minor revision before acceptance. The remaining points are mostly editorial and clarificatory:

1. Please ensure that the revised manuscript consistently uses association-based wording throughout, especially in the Abstract, Discussion, and Conclusions.
2. The limitations concerning exposure characterization should remain clearly visible in the final version, as the lack of a common objective RHI exposure metric remains an important constraint.
3. Please double-check that all cognitive scores described as normalized, proportion-based, or bias-corrected are labelled consistently across the Methods, tables, and figure legends.
4. The decision not to trim MST reaction-time data is now transparent, but it would be helpful to briefly justify this choice or acknowledge it as a minor analytical limitation.
5. Please ensure that the newly added estimated marginal means, confidence intervals, and adjusted pairwise differences are clearly presented and aligned with the Results text.
6. A final language edit is recommended to improve clarity and remove minor typographical/formatting issues, including corrupted symbols in effect-size notation.

Author Response

Manuscript ID: applsci-4376911 - Revision SUBMITTED

Manuscript: “Pattern Separation and Related Cognitive Functions in Combat and Contact Sports Athletes: Working Memory, Attention, and Processing Speed” (Applied Sciences)

We thank both reviewers for their evaluation of the revised manuscript. We are grateful to Reviewer 1 for indicating no further comments, and to Reviewer 2 for the positive assessment and the additional clarifying suggestions. Below we respond to each of the remaining points. All changes introduced in this round are shown as tracked changes in the revised manuscript.

Reviewer 2

Comment 1. Please ensure that the revised manuscript consistently uses association-based wording throughout, especially in the Abstract, Discussion, and Conclusions.

Response. We have re-examined the Abstract, Discussion, and Conclusions to verify the consistent use of association-based phrasing. Causal expressions had already been reformulated in the previous revision (e.g., “associated with”, “consistent with the possibility that”, “may be associated with”). Statements that describe the observed data (e.g., “fighters exhibited significantly lower LDI scores”) have been retained, as they report results rather than asserting causation. For terminological consistency, the attributive form “RHI exposure” is now used uniformly in place of “RHIs exposure”.

Comment 2. The limitations concerning exposure characterization should remain clearly visible in the final version, as the lack of a common objective RHI exposure metric remains an important constraint.

Response. This limitation is retained as the first and most prominent point in the Limitations section: the absence of an objective, individual-level RHI exposure metric common to all groups, the reliance on incomplete sport-specific self-report proxies, and the resulting exploratory and associative status of the between-sport comparisons are all stated explicitly.

Comment 3. Please double-check that all cognitive scores described as normalized, proportion-based, or bias-corrected are labelled consistently across the Methods, tables, and figure legends.

Response. The scoring of each measure is now described consistently across the Methods (Section 2.3), the note to Table 3, and the legend of Figure 1: the WAIS-IV subtests and the Attentional Matrices are reported as normalised scores (0–1 range); the N-back tasks as proportions of correct responses (accuracy); and the MST indices (LDI and REC) as defined in Section 2.2.

Comment 4. The decision not to trim MST reaction-time data is now transparent, but it would be helpful to briefly justify this choice or acknowledge it as a minor analytical limitation.

Response. We have added a brief justification and acknowledgment in Section 2.2. Reaction-time analyses were conducted on correct responses only, without trimming, in order to avoid imposing arbitrary exclusion thresholds and to preserve all valid responses; we now explicitly acknowledge this as a minor analytical limitation, since untrimmed latencies may remain somewhat more sensitive to occasional extreme values.

Comment 5. Please ensure that the newly added estimated marginal means, confidence intervals, and adjusted pairwise differences are clearly presented and aligned with the Results text.

Response. The estimated marginal means (adjusted for age and education) with 95% confidence intervals are reported in Table 4, and the corresponding adjusted pairwise differences with 95% confidence intervals are reported in the Results and aligned with the table. To prevent any apparent inconsistency, we have added a note to Table 4 clarifying that the pairwise differences and their confidence intervals were obtained from the fitted ANCOVA model, so that any minor discrepancy relative to the differences computed on the rounded marginal means reflects rounding only.

Comment 6. A final language edit is recommended to improve clarity and remove minor typographical/formatting issues, including corrupted symbols in effect-size notation.

Response. We have carried out a final language pass. A grammatical error in the Statistical Analyses section was corrected (“a large effects” → “large effects”), and terminology was harmonised as noted above. The partial eta-squared notation is rendered consistently throughout the manuscript.

We hope that these clarifications adequately address the remaining points and we thank the reviewers and the editor for their constructive guidance.

 

On behalf of all authors,

Alessandro Santirocchi