Differences in neuroception, namely different experienced activation patterns of the central nervous system, are predicted to appear as recognizable signs in pictorial artefacts conducted by clients. As an external validation, 65 pictures produced within a randomized trial with parallel treatment arms were analysed according to assessment tool criteria. Research participants were gynaecological cancer survivors (N = 57), post oncological treatment, who participated in arts-based psychotherapy interventions (Brief-Music Journeys, KMR; Korta musikresor), an adaptation of The Bonny Method of Guided Imagery and Music. The women produced artwork of their body image experiences at three different time points, before, after psychotherapy, and follow-up. Each picture was measured regarding the intended patterns of neuroception with fair to moderate agreement between the raters, with weighted kappa values of .61 (95% CI .39–.83, p = .001) and .59 (95% CI .36–.82, p < .001). Inter-rater evaluations of their pictures at baseline differed significantly from pictures created at post-test, p < 0.001, and co-variated with self-assessed measures on depression, anxiety and QoL (MADRS, HADS-A, and EORTC-QLQ-C30) before and after interventions. The importance of adding qualitative or nonparametric measures in evaluation is highlighted.