Cognitive Dysfunction and Criminal Behavior: Investigating Executive Functions in Convicted Individuals

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript investigates executive functions and decision-making among incarcerated individuals using MoCA, Digit Span, WCST, FAB and the Iowa Gambling Task (IGT). The topic is important and potentially publishable in cognitive/forensic journals, but the manuscript in its current form has substantial conceptual, methodological, statistical, and reporting deficiencies. These prevent confident interpretation and require extensive revision.

The authors treat Duration of Sentence Imposed as a proxy for crime severity. This is a coarse measure and may conflate legal policy, plea decisions, prior record, and judicial discretion with the purported construct (severity of criminal behavior). Please justify this operationalization with references, and discuss limitations. Were legal classifications (e.g., offense codes) available to validate this proxy? If not, the authors must explicitly acknowledge the risks of interpreting sentence length as crime severity.

The sample size (n = 30) is small given the many subgroup comparisons (recidivists vs. first offenders; violent vs. non-violent; long vs. short sentences; IGT bins; WCST domains). How were these subgroup labels created (cutoffs, coding rules)? Several subgroups are extremely small (e.g., non-violent n = 5; repeat offenders n = 8). The authors should state the study’s power to detect effects (post-hoc power or better — preferably a priori). If the sample is underpowered for inferential claims, results should be presented as exploratory and effect sizes prioritized over p-values.

The cognitive performance of incarcerated individuals can be strongly influenced by psychotropic medication, current withdrawal or intoxication, psychiatric diagnoses (e.g., psychosis, major depression), and substance use history. The manuscript records substance-use history but does not report current medication or mental-health status. Please clarify:

Were participants currently taking psychotropic medications? If yes, which classes and how many participants? How were active withdrawal/intoxication screened and controlled? Were major psychiatric diagnoses recorded and considered in analyses?

Cognitive testing conditions (time of day, noise, recent sleep, food intake, test order) and assessor bias can influence results. Please report: Were assessors blind to participant criminal subgroups? Were tests administered at a standardized time? Was test order counterbalanced or fixed? Was there a practice/training trial for the IGT?

There are passages that infer neural mechanisms or causal relationships from behavioural tests (e.g., implying orbitofrontal dysfunction). Please tone down causal/neuroanatomical claims unless neuroimaging or converging physiological data are available. Interpretation should remain at the behavioral/cognitive level unless strongly justified.

The introduction cites executive dysfunction broadly, but the manuscript lacks a clear mechanism (model) linking specific executive subcomponents (hot vs. cold) to distinct criminal behaviors and recidivism. I recommend:

Introduce an explicit conceptual model (diagram) linking (a) cold EF (working memory, cognitive flexibility, inhibition), (b) hot EF/affect-laden decision-making (IGT), (c) mediators (substance use, intelligence, psychiatric conditions), and (d) behavioral outcomes (type of offense, recidivism).

Use the hot/cold EF distinction to motivate specific hypotheses (e.g., “IGT performance will be associated with impulsive/instrumental offending”).

Hypotheses should be explicit and testable. Currently hypotheses are implicit. Recast them as numbered hypotheses with the expected direction of effect and the test used.

Provide a clear participant flow (CONSORT-style): number screened, excluded (and reasons), consented, assessed, and included in analyses. Explain eligibility criteria (age range, language proficiency, medico-legal exclusions). Specify whether the sample is consecutive, convenience, or purposive.

For each instrument (MoCA, WAIS Digit Span, FAB, WCST, IGT), provide a short rationale: what construct it measures, why relevant to the hypotheses, and norms used for comparison.

For WCST and other tests where Portuguese norms were referenced, specify which normative dataset was used, how age/education adjustments were applied, and whether the present sample matches the normative sample on key demographics.

The IGT can be sensitive to instructions, trials, and scoring: Version used (real money vs. hypothetical; computerized/hardware). Total trials, block structure, and whether practice trials were given. How nets (Net1–Net5) were computed, and whether loss/gain magnitudes follow standard Bechara parameters. Were deck contingencies standard and counterbalanced?

Precisely define how “violent” vs. “non-violent” and “recidivist” vs. “first offender” were coded. Provide a table with crime categories and counts (you have some in Table but ensure coding clarity). For sentence duration and length of imprisonment: state how medians were computed and why the chosen cutoffs were used instead of continuous modeling.

You state ethics approval; additionally describe the informed consent procedures (was participation voluntary, any incentives, confidentiality specifics).

The authors justify parametric tests by their robustness; however the manuscript notes multiple violations of normality (e.g., MoCA, WCST). With n = 30 and multiple dependent variables, please:

Re-run key analyses using appropriate non-parametric alternatives (e.g., Mann–Whitney U for between-group comparisons; Friedman test for repeated measures) or robust methods (rank-transformed ANOVA, bootstrapped confidence intervals). Present both parametric and non-parametric results where relevant and explain any divergences.

Alternatively, use linear mixed models (LMM) for repeated measures (Net/Deck) which better handle missingness and relax sphericity assumptions.

When using MANCOVA or ANCOVA (e.g., WCST controlling for age), test and report homogeneity of regression slopes, multivariate normality, and multicollinearity diagnostics. If assumptions are violated, present alternative analyses. Report test statistics fully (degrees of freedom, F, p, partial η² or other effect size) for each main effect and interaction. Avoid simply reporting p < .05.

You perform many post-hoc comparisons (IGT deck differences, multiple WCST indexes). State and apply a principled correction for multiple testing (Bonferroni is conservative; consider Holm or False Discovery Rate depending on familywise grouping). Report adjusted p-values. For all reported effects, include effect sizes (Cohen’s d, partial η²) and 95% CIs. Given small samples, p-values alone are uninformative.

Improve captions to be interpretable without referring to the main text. For each figure, indicate sample sizes and what error bars represent (SE vs. 95% CI). Table 2 and WCST tables appear crowded. Consider moving extensive descriptive statistics to Supplementary Material and retaining a concise summary table in the main text.

The text frequently compares sample means to normative means. For each comparison, report the normative mean and SD, and provide a statistical test if claiming differences (e.g., one-sample t-test or z-score norms), or else phrase cautiously.

Deck B preference is reported; but be explicit whether deck choice patterns reflect risk-taking or sensitivity to reward magnitude vs. frequency. The literature shows that increased choice of deck B can reflect sensitivity to high immediate rewards despite long-term losses — discuss alternative interpretations.

The Discussion sometimes generalizes from limited subgroup results (e.g., primary offenders showing certain deficits) without robust statistical support. Reword to avoid causal claims and overstatements.

The discussion relies on older or general references. Include recent systematic reviews and meta-analyses (post-2018) on executive function in offenders and the validity of tasks like IGT in forensic samples.

If suggesting neuroanatomical mechanisms, explicitly state that interpretations are inferential from behavioral tasks and that neuroimaging/electrophysiology would be required for direct claims.

The manuscript mentions rehabilitation implications — expand this with concrete, evidence-based recommendations (e.g., cognitive remediation strategies, structured activity programs) and indicate caveats given the exploratory nature of current data

Author Response

Dear Editor,

Thank you very much for the opportunity to revise and improve our study. We also thank the reviewers for their constructive feedback on our manuscript. Their comments led us to reflect carefully on our approach, and as a result, we have revised several aspects of the manuscript and refined some of our original ideas in response to the reviewers’ feedback. In the attached file we provide the detailed responses to each comment from the reviewers.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

This study examines executive functioning and decision-making among incarcerated individuals, focusing on how severity of criminal behavior and duration of imprisonment relate to neurocognitive performance. The article is interesting and well-written, though I am not sure I understand all the statistical approaches used in the analysis. One piece of advice is to better organize the introductory section on the brain and behavior. It is a bit jumbled.

The authors situate their hypotheses within contemporary empirical work showing that individuals who commit severe or violent offenses tend to display impairments in flexibility, inhibition, and self-regulation. The study’s analytical approach acknowledges key confounders—most notably age—which is appropriately controlled due to its dual association with sentence variables and neurocognitive performance. This methodological step enhances the internal validity of the reported findings, though those findings are at times quite surprising.

The results present a complex picture: global cognitive functioning in the sample does not appear markedly impaired relative to normative data, suggesting that the cognitive consequences of incarceration or criminal history may be domain-specific rather than generalized. The evidence for deficits in mental flexibility and interference control among individuals with longer sentences aligns with theoretical models of executive dysfunction in offending populations, yet the absence of effects in some measures raises questions about task sensitivity, construct operationalization, or sample characteristics.

As for limitations to the study, the small and uneven sample undermines statistical power and complicates interpretations of group differences. The absence of additional measures, and the limited assessment of both “cold” and “hot” executive functions, further restricts the scope of the conclusions. Further, the study is not longitudinal, making firmer conclusions about potential causal order very problematic. These issues should be more clearly addressed by the authors.

Overall, the study offers a thoughtful, empirically anchored contribution to the literature on cognitive functioning in incarcerated populations. Its findings reinforce the relevance of executive deficits—particularly in flexibility and interference control—in understanding criminal behavior and recidivism. But, the limitations to the study should be better addressed. 

Author Response

Dear Editor,

Thank you very much for the opportunity to revise and improve our study. We also thank the reviewers for their constructive feedback on our manuscript. Their comments led us to reflect carefully on our approach, and as a result, we have revised several aspects of the manuscript and refined some of our original ideas in response to the reviewers’ feedback. In the attached file we provide the detailed responses to each comment from the reviewers.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

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