Are you seeing this? An investigation into the variability of mental imagery and propensity of aphantasia in a non-self-diagnosed population

Mental imagery is the experience of visual representations in the “mind’s eye” without external stimulation. A portion of the population, ranging somewhere between 0.7-15.3% (Betts, 1909; Faw, 2009; Zeman et al., 2020; Dance & et al., 2022; Beran & et al., 2023) has an inability to voluntarily generate mental images, a phenomenon referred to as aphantasia. Studies investigating the prevalence of aphantasia have used measures such as the Vividness of Visual Imagery Questionnaire-2 (VVIQ) (Marks, 1995), Spontaneous Use of Imagery Scale (SUIS) (Nelis & et al., 2014), and Questionnaire upon Mental Imagery (QMI) (Sheehan, 1967). However, the vast majority of prior research has relied on self-selected sampling, i.e., individuals diagnosing themselves with aphantasia. In the present study, participants from a healthy population were sampled. All completed the VVIQ-2, SUIS, and QMI to measure mental imagery ability. Afterward, they reported any familiarity with aphantasia and whether they felt they had the condition. A wide range of mental imagery abilities were found between individuals in our sample, only a minority of which falling in the aphantasia range. However, a significant difference was found between each of these measures indicating variations related to convergent and divergent validity. Participant knowledge of aphantasia and questions related to “self-diagnosis” will be discussed as it pertains to aphantasia generally and to each of our measures. The present study highlights the extensive range of mental imagery abilities as well as the variability between measures used to assess imagery and aphantasia. Unlike previous studies examining aphantasia, participants here were not aware we were looking for individuals with aphantasia and they were not asked to self-diagnose. This study is the first of its kind to examine the impacts self-diagnosis and familiarity with aphantasia may have on reporting mental imagery ability.