AbstractNeurofeedback (NF) is a form of biofeedback that involves individuals monitoring and shifting brain activity towards a desired direction. The objective of this study was to investigate whether there are differences between NF learners and non-learners on psychometric traits such as the NEO PI-R personality factors, self-regulation questionnaire (SRQ) and the need for cognition scale (NFC). A total of 34 participants were randomly allocated to a single-blind randomised sham-controlled protocol 3-arm study of single-session theta NF. Twelve participants were administered a spatially defined frontal-midline theta (FM-theta) group, 11 to a functionally defined medial temporal/parietal lobe (MTL-theta) group and 11 allocated to a yoked sham NF group. The baseline session included screening of participants, trait-based behavioural measures (SRQ, NFC and NEO PI-R) and the completion of cognitive tasks with electroencephalography (EEG) recording to determine individualised peak theta activity for NF training. NF learners and non-learners were evaluated using changes in absolute theta power and the percentage of time spent above threshold using Spearman’s correlation coefficient from a total of 30-minutes of NF exposure. Significant differences in psychometric traits between NF learners and non-learners differed depending on learning metrics. Results indicated that NF learners reported higher SRQ total scores, SRQ decision making, SRQ goal setting subfactors and NEO PI-R conscientiousness, but were significantly lower in NEO PI-R extraversion compared to non-learners. This study demonstrates that learning outcomes vary based on the metrics used and emphasises the importance of selecting appropriate learning metrics and further examination of learning within sham NF training.