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This is the response:

The proposed research topic has strong potential but could benefit from refinements to align with current research trends and methodological clarity. Here's a structured analysis and suggested modifications:

### Key Considerations from Current Research

1. **Comparative vs Combined Approaches**

Existing studies frequently examine tDCS *combined* with exercise interventions rather than direct comparisons[1][3][6]. HIIT alone shows cognitive benefits[1][5], while tDCS effects are context-dependent and often tested alongside physical/cognitive tasks[3][7]. A direct comparison may overlook synergistic effects observed in combined protocols[1][6].

2. **fNIRS Application**

fNIRS is validated for measuring cortical hemodynamics during dynamic tasks (e.g., balance, exercise)[2][5][8]. However, its utility in sedentary populations requires justification—consider specifying whether measurements occur *during* interventions or post-exercise[5][8].

3. **Outcome Specificity**

The title broadly mentions "brain mechanisms" but should target explicit neurocognitive or behavioral outcomes (e.g., prefrontal cortex activation during inhibitory control, motor learning efficiency)[1][5][8].

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### Suggested Modifications

**Option 1 (Combined Intervention):**

*"Enhancing Cognitive-Motor Functions in Sedentary College Students: fNIRS-Based Analysis of Combined HIIT and tDCS Effects on Dorsolateral Prefrontal Cortex Activation"*

- **Rationale:** Focuses on synergistic mechanisms (supported by[1][6]), specifies brain regions, and aligns with fNIRS strengths in measuring prefrontal activity during/after exercise[5][8].

**Option 2 (Mechanistic Comparison):**

*"Differential Neurophysiological Effects of tDCS and HIIT in Sedentary Adults: A Functional Near-Infrared Spectroscopy Study of Prefrontal and Motor Cortices"*

- **Rationale:** Directly compares modalities while emphasizing cortical specificity and fNIRS methodology[2][5].

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### Critical Feedback

- **Avoid Ambiguity:** Clarify whether tDCS targets motor or cognitive regions (e.g., M1 vs DLPFC)[3][6].

- **Population Justification:** Highlight why sedentary students are relevant—e.g., baseline neuroplasticity differences vs athletes[6][7].

- **Control Conditions:** Ensure the design includes sham tDCS and passive control groups to isolate effects[1][7].

These adjustments would enhance methodological rigor and novelty while leveraging fNIRS capabilities for exercise neuroscience research[5][8].

Citations:

[1] https://pubmed.ncbi.nlm.nih.gov/38875731/

[2] https://pmc.ncbi.nlm.nih.gov/articles/PMC3294084/

[3] https://pmc.ncbi.nlm.nih.gov/articles/PMC7268738/

[4] https://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0220363

[5] https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2024.1327822/full

[6] https://pmc.ncbi.nlm.nih.gov/articles/PMC11220198/

[7] https://www.nature.com/articles/s41598-024-74941-0

[8] https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2020.00724/full

[9] https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2024.1365530/full

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Thank you very much for your detailed reply. It is of great help to me.