Metacognitive beliefs and behavioural indices aligned with large-scale networks plausibly shape day-to-day psychosocial functioning, especially under conditions of persistent stress and fatigue. However, their joint structure and group-level comparability remain under-specified. In a cross-sectional multi-group design (men and women), we administered the MCQ-30, the Fatigue Severity Scale, behavioural proxies of fronto-parietal, salience and default-mode network tendencies, and the Index of Psychosocial Functioning (IPF). Note that the three neurocognitive instruments do not measure large-scale brain networks per se. They are behavioural proxies that characterise probable patterns of attention/control, self-referential processing, and cue detection/switching putatively linked to activity within the frontoparietal (executive), default-mode, and salience networks; accordingly, all inferences are at the level of behaviour/cognition rather than direct neurophysiology. Using multi-group exploratory structural equation modelling (ESEM) with target rotation, we specified a three-factor measurement solution for the metacognitive– behavioural indicators, tested configural, metric and partial scalar invariance across sex, and regressed a latent IPF outcome on the three factors while controlling for age and education. Missingness was handled with FIML and MLR; WLSMV sensitivity analyses and bootstrap confidence intervals were used where appropriate. The three-factor ESEM structure showed good fit in each group and supported metric and partial scalar invariance. A factor reflecting threat/uncontrollability beliefs displayed robust negative associations with psychosocial functioning, whereas executive confidence/goal-directedness was positively associated; self-focus/monitoring contributed little or inconsistently. Effects were robust to estimator choice and to freeing a small subset of intercepts for partial scalar invariance. Clean separation of predictors and outcome (IPF as a latent criterion) clarifies that metacognitions centred on perceived threat and loss of control undermine functioning, while executive confidence aligned with FPN-like behaviour supports it. Therapeutically, the findings prioritise dampening uncontrollability beliefs and strengthening executive stamina. Behavioural network indices should be interpreted as proxies rather than neural measurements.

The authors have declared no competing interest.

This study did not receive any funding

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The Ethics Committee (IRB) of the Department of General and Medical Psychology, O.O. Bogomolets National Medical University, Kyiv, Ukraine, approved this study (Protocol No. 11, 16 January 2025).

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