Aphantasia and psychological disorder: Current connections, defining the imagery deficit and future directions

Health Literacy-Based Heart Failure Self-care (H2Lit) Application: Development and Usability Testing

The purpose of this study was to describe the development of a health literacy-focused heart failure self-care intervention (H2Lit Web-based app) and assess its usability using an online testing platform. We used an iterative approach, wherein participants evaluated more refined versions of H2Lit over four rounds of testing. Healthy participants were recruited for the earlier rounds of testing, and participants with heart failure were recruited for the final round. A total of 44 participants (10 participants with heart failure) were enrolled in the study. The participants had a mean age of 47.6 years, 57% were female, 70% identified as White, 70% were college-educated, and 34% had low health literacy. Using the System Usability Scale (score range of 0 to 100), the participants gave H2Lit a mean usability score of 74.1 in round 1, 54.3 in round 2, 85.3 in round 3, and 82.5 in round 4. H2Lit's usability score did not significantly differ between participants with adequate health literacy and those with low health literacy after controlling for age, sex, education level, and computer use duration. Further research is needed to determine the effect of the H2Lit intervention on heart failure self-care and heart failure-related outcomes.

Through the mind's eye: mapping associations between hoarding tendencies and voluntary and involuntary mental imagery

BACKGROUND

Preliminary evidence suggests that mental imagery may be an important clinical feature in hoarding. Individuals who hoard use objects as receptacles for memories, and experience more frequent, intrusive and distressing images compared with the general community. However, the specific nature of these associations remains poorly understood.

AIMS

We aimed to investigate whether hoarding traits were related to the ability to voluntarily generate imagery in different sensory modalities, and uniquely with the tendency to experience negative intrusive imagery. We also aimed to understand the mechanism by which mental imagery experiences may confer vulnerability to hoarding problems.

METHOD

Undergraduates (n=328) completed questionnaires assessing hoarding, beliefs about objects, imagining ability across the senses, and negative intrusive imagery, as well as symptom measures of depression, obsessive-compulsive disorder and post-traumatic stress. We conducted Pearson's correlations, hierarchical regressions, and mediational analyses.

RESULTS

Hoarding tendencies were associated with reduced visualising ability, but not with the capacity to deliberately generate imagery in other senses. Hoarding was also uniquely associated with the tendency to experience negative involuntary imagery when controlling for symptoms of depression, obsessive-compulsive disorder, and post-traumatic stress. Object-memory beliefs partially mediated the relationship between hoarding and reduced visualising ability. Object attachment partially mediated the relationship between hoarding and negative intrusive imagery.

CONCLUSIONS

Results suggest that visualisation difficulties may promote a reliance on objects to facilitate recall, and experiencing negative intrusive imagery may strengthen object attachment. Findings may inform imagery-based conceptualisations and treatments of hoarding problems, such as imagery training or modification interventions.

Beyond self-report: Measuring visual, auditory, and tactile mental imagery using a mental comparison task

Finding a reliable and objective measure of individual differences in mental imagery across sensory modalities is difficult, with measures relying on self-report scales or focusing on one modality alone. Based on the idea that mental imagery involves multimodal sensorimotor simulations, a mental comparison task (MCT) was developed across three studies and tested on adults (n = 96, 345, and 448). Analyses examined: (a) the internal consistency of the MCT, (b) whether lexical features of the MCT stimuli (word length and frequency) predicted performance, (c) whether the MCT related to two widely used self-report scales, (d) response latencies and accuracies across the visual, auditory, and tactile modalities, and (e) whether MCT performance was independent of processing speed. The MCT showed evidence of reliability and validity. Responses were fastest and most accurate for the visual modality, followed by the auditory and tactile. However, consistent with the idea that self-report questionnaires index a different aspect of mental imagery, the MCT showed minimal correlations with self-report imagery. Finally, relations between MCT scales remained strong after controlling for processing speed. Findings are discussed in relation to current understanding and measurement of mental imagery.

Sensory representations in primary visual cortex are not sufficient for subjective imagery

The contemporary definition of mental imagery is characterized by two aspects: a sensory representation that resembles, but does not result from, perception, and an associated subjective experience. Neuroimaging demonstrated imagery-related sensory representations in primary visual cortex (V1) that show striking parallels to perception. However, it remains unclear whether these representations always reflect subjective experience or if they can be dissociated from it. We addressed this question by comparing sensory representations and subjective imagery among visualizers and aphantasics, the latter with an impaired ability to experience imagery. Importantly, to test for the presence of sensory representations independently of the ability to generate imagery on demand, we examined both spontaneous and voluntary imagery forms. Using multivariate fMRI, we tested for decodable sensory representations in V1 and subjective visual imagery reports that occurred either spontaneously (during passive listening of evocative sounds) or in response to the instruction to voluntarily generate imagery of the sound content (always while blindfolded inside the scanner). Among aphantasics, V1 decoding of sound content was at chance during voluntary imagery, and lower than in visualizers, but it succeeded during passive listening, despite them reporting no imagery. In contrast, in visualizers, decoding accuracy in V1 was greater in voluntary than spontaneous imagery (while being positively associated with the reported vividness of both imagery types). Finally, for both conditions, decoding in precuneus was successful in visualizers but at chance for aphantasics. Together, our findings show that V1 representations can be dissociated from subjective imagery, while implicating a key role of precuneus in the latter.

A Systematic Review of Aphantasia: Concept, Measurement, Neural Basis, and Theory Development

People with aphantasia exhibit the inability to voluntarily generate or form mental imagery in their minds. Since the term "aphantasia" was proposed to describe this, it has gained increasing attention from psychiatrists, neuroscientists, and clinicians. Previous studies have mainly focused on the definition, prevalence, and measurement of aphantasia, its impacts on individuals' cognitive and emotional processing, and theoretical frameworks synthesizing existing findings, which have contributed greatly to our understanding of aphantasia. However, there are still some debates regarding the conclusions derived from existing research and the theories that were constructed from various sources of evidence. Building upon existing endeavors, this systematic review emphasizes that future research is much needed to refine the definition and diagnosis of aphantasia, strengthen empirical investigations at behavioral and neural levels, and, more importantly, develop or update theories. These multiple lines of efforts could lead to a deeper understanding of aphantasia and further guide researchers in future research directions.

Aphantasia and involuntary imagery

Aphantasia is a condition that is often characterized as the impaired ability to create voluntary mental images. Aphantasia is assumed to selectively affect voluntary imagery mainly because even though aphantasics report being unable to visualize something at will, many report having visual dreams. We argue that this common characterization of aphantasia is incorrect. Studies on aphantasia are often not clear about whether they are assessing voluntary or involuntary imagery, but some studies show that several forms of involuntary imagery are also affected in aphantasia (including imagery in dreams). We also raise problems for two attempts to show that involuntary images are preserved in aphantasia. In addition, we report the results of a study about afterimages in aphantasia, which suggest that these tend to be less intense in aphantasics than in controls. Involuntary imagery is often treated as a unitary kind that is either present or absent in aphantasia. We suggest that this approach is mistaken and that we should look at different types of involuntary imagery case by case. Doing so reveals no evidence of preserved involuntary imagery in aphantasia. We suggest that a broader characterization of aphantasia, as a deficit in forming mental imagery, whether voluntary or not, is more appropriate. Characterizing aphantasia as a volitional deficit is likely to lead researchers to give incorrect explanations for aphantasia, and to look for the wrong mechanisms underlying it.

Diversity of aphantasia revealed by multiple assessments of visual imagery, multisensory imagery, and cognitive style

Aphantasia-a condition wherein individuals have a reduced or absent construction of voluntary visual imagery-is diagnosed using either the Vividness of Visual Imagery Questionnaire (VVIQ) or self-identification. However, a significant discrepancy exists between the proportions of aphantasia in the populations assessed using these two criteria. It is unclear why the reported proportions differ excessively and what percentage of people cannot form visual imagery. We investigated the replicability of the proportion of people with aphantasia using both criteria in the same population of participants. Therefore, we explored the potential causes of the discrepancy and characteristics of putative aphantasia in terms of multisensory imagery, cognitive style, and face recognition ability. First, we conducted an online sampling study (Study 1: N = 2,871) using the VVIQ, self-identification of a reduction in visual imagery, Questionnaire upon Mental Imagery (QMI), and Verbalizer-Visualizer Questionnaire (VVQ). We found that 3.7 and 12.1% fulfilled the VVIQ and self-identification criteria, respectively, roughly replicating the proportions reported in previous studies. The self-identification criterion-but not the VVIQ criterion-contains items related to face recognition; hence, we suspected that face recognition ability was factor contributing to this discrepancy and conducted another online sampling study (Study 2: N = 774). We found a significant correlation between VVIQ and face recognition ability in the control group with self-identification, but not in the group defined by low VVIQ (VVIQ ≤32). As the participants in the control group with self-identification tended to exhibit moderately high VVIQ scores but low face recognition ability, we reason that the discrepancy can be partially explained by the contamination of individual differences in face recognition ability. Additional analyses of Study 1 revealed that the aphantasia group included participants who lacked all types of sensory imagery or only visual imagery in multisensory imagery and exhibited a non-specific cognitive style. This study indicates that the VVIQ alone may be insufficient to diagnose individuals who report an inability to form visual imagery. Furthermore, we highlight the importance of multiple assessments-along with the VVIQ-to better understand the diversity of imagery in aphantasia.