Dear Editor

The research by Daneshvari and others ¹ represents an ambitious and important endeavor to explore the neurocognitive and emotional profiles of child sexual abuse (CSA) perpetrators within an Iranian context. The study employed a multi-modal approach, utilizing self-report measures, cognitive tasks, and physiological assessments, such as functional near-infrared spectroscopy (fNIRS) and polygraphy. The attempts to identify objective biological and cognitive correlates of such behavior are of significant scientific interest, particularly at the intersection of brain function and deviant behavior. However, the study’s methodology, interpretation of findings, and the inherent complexities of this research area warrant careful consideration and raise several points for discussion.

The authors report several key findings. First, the experimental group (EG) of CSA perpetrators demonstrated a greater tendency toward homosexuality (in terms of past, present, and ideal orientation) than the control group (CG). Second, using the mini-mental state examination (MMSE), cognitive distortions were found to be more common in the EG. Third, a history of being sexually abused between the ages of 12 and 16 was significantly associated with perpetrating CSA. Fourth, during the Stroop task, CSA perpetrators exhibited poorer cognitive performance, particularly in reaction time and the number of unanswered questions, in the condition without distracting images. They also displayed different patterns of hemodynamic changes in the frontal poles (Fp1 and Fp2), as measured by fNIRS. Specifically, the fNIRS data suggested reduced activity/blood supply in the Fp1 region of the EG during the cognitive task. Finally, polygraph data indicated less emotional control—reflected in higher skin conductance and heart rate—in the EG when viewing images of children.

The attempt to integrate subjective reports, cognitive performance, and physiological measures is a commendable strength, as it aims for a more holistic understanding. The use of fNIRS, a portable neuroimaging technique, is particularly innovative in this challenging research population. ² Furthermore, the finding that a history of abuse was linked to perpetration aligned with existing literature on the cycle of abuse, a crucial point for preventative strategies. ^{3 , 4}

However, several methodological and interpretative aspects warrant critical reflection. First, the sample sizes were very small (n=12 for EG, n=13 for CG), which severely limited statistical power and the generalizability of the findings. With such small groups, significant P values must be interpreted with extreme caution, as they might be susceptible to type I errors or reflect large but unstable effect sizes.

The interpretation of the fNIRS data ² also requires a more nuanced discussion. The authors linked changes in oxyhemoglobin (HbO) and deoxyhemoglobin (HbR) directly to “blood supply and activity” and then to “cognitive control” or the “mitigation of disturbing stimuli”. While fNIRS measures hemodynamic responses correlated with neural activity, the precise cognitive processes reflected by changes in Fp1/Fp2 regions during a Stroop task, particularly with emotionally charged distractor images, are highly complex. Attributing decreased HbO/HbR in Fp1 in the EG solely to “weaker performance” or “decrease in activity” was an oversimplification, especially without more detailed source localization or correlation with specific cognitive sub-processes (e.g., inhibition, emotional interference). The frontal pole is involved in a myriad of higher-order functions; the observed changes could reflect altered emotional processing, attentional bias, or the use of different cognitive strategies rather than a simple decrease in “cognitive efficiency”. ⁵

Furthermore, the use of the MMSE to assess “cognitive distortion” is highly unusual. The MMSE is a general cognitive screening tool designed primarily for dementia; it is not a validated instrument for measuring offense-supportive cognitive distortions. While the authors might be referring to overall cognitive impairment, the term “cognitive distortion” in this context typically implies specific maladaptive thought patterns, which are more appropriately assessed with specialized questionnaires (such as the Bumby Molest Scale, which was also used in the study, though its correlation with MMSE was not detailed).

Regarding the polygraph findings, the observation of greater physiological arousal in the EG when viewing images of children was consistent with theories of deviant arousal. ⁶ However, it is critical to note that the polygraph measures physiological arousal—not “emotional control” or the veracity of statements. ⁷ Its application in forensic settings remains highly debated due to its susceptibility to countermeasures and the non-specificity of physiological signals it captures. ⁷ Therefore, interpreting polygraph data as a direct measure of emotional control is problematic.

Finally, the broad conclusion that CSA perpetrators “seem to have a poorer neurocognitive function” requires qualification. While the Stroop task data indicate performance differences in a specific cognitive domain, a more comprehensive neuropsychological battery assessing various domains supporting such a general conclusion would require a more comprehensive neuropsychological battery assessing various domains, executive functions, attention, memory, and processing speed.

Future research in this critical area, while ethically and logistically challenging, would benefit from several key improvements: larger, well-matched sample sizes; comprehensive, standardized neuropsychological testing; more sophisticated neuroimaging paradigms with careful task design to isolate specific cognitive and emotional processes; and longitudinal studies to understand developmental trajectories. The integration of genetic, neurodevelopmental, and detailed psychosocial histories would be invaluable.

In conclusion, Daneshvari and colleagues ¹ conducted a commendable pilot study in a complex and sensitive research domain. Their pilot study offered preliminary, hypothesis-generating insights into potential neurocognitive and emotional differences in CSA perpetrators. However, the discussed methodological limitations, particularly the small sample size and the broad interpretation of some measures, necessitate that these findings be viewed as exploratory. They underscored the immense challenge and the critical need for continued, rigorous, and ethically sound multidisciplinary research to understand and ultimately prevent child sexual abuse.

Acknowledgment

This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF), funded by the Ministry of Education (RS 2023-00237287) and the professor research program of KOREATECH in 2025. Regarding AI-assisted technologies (such as LLMs, chatbots, or image creators), none were used in the production of this submitted work.

Declaration of AI

The authors declare that no AI tools were used in the preparation of this manuscript.

Conflict of Interest

None declared.

References

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