What is the relationship between Aphantasia, Synaesthesia and Autism?

Assessing visual mental imagery abilities in cerebral visual impairment

Visual imagery refers to the ability to create voluntary mental representations in the absence of corresponding visual stimuli, and current evidence suggests that it shares common neural mechanisms with visual perception. Cerebral visual impairment (CVI) is a brain-based visual disorder caused by early neurological injury and maldevelopment of central visual processing pathways and areas. Individuals with CVI often present with a complex visual profile, including deficits related to higher-order visual processing. However, the impact of visual maldevelopment on imagery abilities in this population has not been extensively characterized. We used the Vividness of Visual Imagery Questionnaire (VVIQ) to investigate visual imagery abilities in a cohort of CVI participants (n = 25, mean age = 22.48 years ± 12.31 SD) compared to controls with neurotypical vision and development (n = 25, mean age = 22.88 years ± 4.94 SD). We found that individuals with CVI had significantly lower VVIQ scores (mean = 41.84 ± 18.61 SD) than controls (mean = 62.48 ± 13.07 SD), after controlling for age and verbal IQ level. Within the CVI group, visual imagery abilities were not significantly different when separated by baseline visual acuity, gestational status, or co-occurrence of autism spectrum disorder. These results suggest that impaired visual imagery may represent an important feature characterizing the complex visual profile of CVI.

The vividness of visualisations and autistic trait expression are not strongly associated

A minority of people (Aphantasics) report an inability to visualise. Aphantasia has been linked to Autism - a neurodevelopmental condition affecting social interactions. There is a risk of a circular logic informing proposed links, as the most popular metric of autistic traits, the Autism-Spectrum Quotient (AQ), has an Imagination subscale with items relating directly and indirectly to imagery. We tested for inter-relationships between imagery vividness ratings and the expression of autistic traits, using metrics that do and do not encompass an Imagination subscale. We also conducted hierarchical linear regression analyses to assess the contributions of different AQ subscale scores to imagery inter-relationships. Only in our highest-powered study (N = 308) were we able to detect a weak inter-relationship between AQ scores and imagery, independent of the Imagination subscale. We suggest that only a weak inter-relationship should exist, as many autistic people describe themselves as visual thinkers who have strong imagery.

How Interoception and the Insula Shape Mental Imagery and Aphantasia

A major question in cognitive neuroscience is understanding the neural basis of mental imagery, particularly in cases of its absence, known as aphantasia. While research in this field has focused on the role of sensory domains, we propose that the key to understanding imagery lies in the intertwining of sensory processing and autonomic responses. Interoception plays a crucial role in mental imagery by anchoring experiences in first-person physiological signals, providing a self-referential perspective, and grounding the imagery in the body while also enabling its emotional aspects. Moreover, interoception contributes to the sense of agency and volitional control, as well as body schema-hallmarks of voluntary mental imagery. Therefore, imagery should be approached as an integrated phenomenon that combines sensory-specific information with interoceptive signals. At the neural level, this process engages the insula and anterior cingulate cortex (ACC), regions vital for synthesizing information across cognitive, emotional, and physical domains, as well as for supporting self-awareness. From this perspective, aphantasia may reflect a suboptimal functioning of the insula/ACC, which can account for its associations with deficits in autobiographical memory, emotion perception, and conditions such as autism and dyspraxia.

Reading between the lines: exploring the discriminative ability of the Short-Story Task in identifying autistic individuals within autism outpatient services

Introduction

The correct diagnosis of autistic individuals is an everyday challenge within autism outpatient services. While the short-story task (SST), a task measuring fiction-based mentalizing, has demonstrated promise in differentiating between autistic and non-autistic adults, its discriminative ability has not been investigated in a sample of individuals seeking autism diagnostics at outpatient services.

Methods

This study aimed to evaluate the utility of the SST in individuals seeking autism diagnostics between 2016 and 2022 at the Clinic and Polyclinic for Psychiatry & Psychotherapy of the University of Regensburg at medbo District Hospital Regensburg. The sample consisted of 211 individuals. In 100 of them an autism spectrum disorder has been diagnosed and 111 individuals were diagnosed with other conditions or none at all.

Results

Performance on the SST did not significantly differ between the two groups, and receiver operator curve analysis did not support the SST as a reliable discriminator. However, linear regression analyses revealed that autism diagnosis was the sole significant predictor of SST mentalizing performance. Additionally, specific items of the SST showed significant differences between autistic and non-autistic individuals and constituted a significant predictor of autism diagnosis.

Discussion

While the SST may not be robust enough to accurately identify autistic individuals on its own, it does offer clinicians valuable insights into how individuals interpret others' actions and whether they grasp the broader context of a story versus focusing solely on details.

Differences in ongoing thought between autistic and non-autistic adults

Autistic people may be distinguishable from non-autistic individuals in the content and modality of their thoughts. Such differences potentially underlie both psychological vulnerability and strengths, motivating the need to better understand autistic thought patterns. In non-clinical undergraduates, a recent study found that autistic traits were associated with thinking more in words than images. However, it is unclear whether such differences in thought are present in clinically diagnosed autistic individuals. The current study applied the same methods (multidimensional experience sampling during an N-back task) to examine ongoing thought in autistic and non-autistic adults. We found that autistic individuals showed less variability in the modality of their thoughts between easy and difficult task contexts. While both non-autistic and autistic participants tended to report thinking more in words during the difficult task context, the difference between conditions was significantly smaller for the autistic group. In addition, autistic individuals showed a weaker coupling between task performance and off-task social thinking, a finding that may be related to differences in social processing during the off-task state. Overall, our results provide a clinical replication and extension of previous work, highlighting the differential effects of changing external context on internal mental states in autism.

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.

'Flashforward' mental imagery in adolescents: exploring developmental differences and associations with mental health

BACKGROUND

Future events can spring to mind unbidden in the form of involuntary mental images also known as 'flashforwards', which are deemed important for understanding and treating emotional distress. However, there has been little exploration of this form of imagery in youth, and even less so in those with high psychopathology vulnerabilities (e.g. due to developmental differences associated with neurodiversity or maltreatment).

AIMS

We aimed to test whether flashforwards are heightened (e.g. more frequent and emotional) in autistic and maltreatment-exposed adolescents relative to typically developing adolescents. We also explored their associations with anxiety/depression symptoms.

METHOD

A survey including measures of flashforward imagery and mental health was completed by a group of adolescents (n=87) aged 10-16 (and one of their caregivers) who met one of the following criteria: (i) had a diagnosis of autism spectrum disorder; (ii) a history of maltreatment; or (ii) no autism/maltreatment.

RESULTS

Flashforwards (i) were often of positive events and related to career, education and/or learning; with phenomenological properties (e.g. frequency and emotionality) that were (ii) not significantly different between groups; but nevertheless (iii) associated with symptoms of anxiety across groups (particularly for imagery emotionality), even after accounting for general trait (non-future) imagery vividness.

CONCLUSIONS

As a modifiable cognitive risk factor, flashforward imagery warrants further consideration for understanding and improving mental health in young people. This implication may extend to range of developmental backgrounds, including autism and maltreatment.

Evaluation of a Visual Cognitive Style in Autism: A Cluster Analysis

Cognitive style refers to how individuals perceive their environment and solve problems. Among various cognitive styles documented, verbal and visual styles, including object versus spatial cognition, have been widely studied. "Thinking in pictures" is often associated with autism and characterized by enhanced performance and autonomy of certain perceptual areas. This study aimed to characterize the cognitive style of autistic individuals, focusing on this visual "thinking in pictures" style. We assessed 43 autistic and 42 non-autistic adults using the Object Spatial Imagery Verbal Questionnaire to evaluate three dimensions of their cognitive style: visual object, visual spatial, and verbal. Using a cluster analysis, we identified cognitive style profiles. We then examined manifestations of cognitive style within these profiles, including mental imagery abilities (with the Mental Rotation Test), the vividness of mental images (with the Vividness of Visual Imagery Questionnaire), language abilities (with the Mill Hill vocabulary test), and synesthetic experiences. Our results revealed three distinct cognitive profiles: a visual profile characterized by significant mental imagery and vivid mental images, a visuo-spatial profile associated with strong abilities to manipulate mental images but lower vividness of mental images, and a verbal profile with lower spatial imagery and manipulation abilities. While all profiles were observed in autistic individuals, the visual cognitive profile was the most common. Additionally, we found synesthesia to be more prevalent in the autistic population compared to the non-autistic population. This study confirms that, while not exclusive, a visual cognitive style is prevalent among autistic individuals.

Aphantasia and autism: An investigation of mental imagery vividness

OBJECTIVE

The present study investigated whether autistic adults report different levels of mental imagery vividness than non-autistic adults, and, moreover, if autism is associated with aphantasia which is defined as a condition of reduced or absent voluntary imagery.

DESIGN AND METHODS

Clinically diagnosed and self-identifying autistic participants were compared with non-autistic participants in their mental imagery vividness (vision, sound, smell, taste, touch, bodily sensation and emotional feeling) and autistic traits using an online survey (N = 121).

RESULTS

The autistic group scored significantly lower than the non-autistic group on imagery vividness (d = -0.44), in addition to having a higher proportion of participants scoring at cut-off for aphantasia. Moreover, a similar difference was observed for the emotional feel (η2 = 0.11).

CONCLUSION

The vividness of visual and emotional mental imagery was on average lower for autistic individuals, with a higher proportion presenting at cut-off to be considered an aphantasic.

Non-visual spatial strategies are effective for maintaining precise information in visual working memory

Visual working memory content is commonly thought to be composed of a precise visual representation of stimulus information (e.g., color, shape). Nevertheless, previous research has shown that individuals represent this visual information in different formats, historically dichotomized into "verbal" and "visual" formats. With growing popular knowledge of aphantasia, or the absence of sensory mental imagery, recent studies have demonstrated that individuals with aphantasia perform similarly to individuals with typical imagery on visual working memory tasks. This suggest that the use of non-visual strategies may be sufficient to perform visual working memory tasks, which were previously thought to be strictly visual. To investigate the effects of different strategies on performance in a visual working memory task, we recruited individuals across the visual imagery spectrum and tested their ability to identify relatively small (3°), medium (6°), or large (10°) changes in the degree of orientation of gratings held in working memory. Subsequently, participants indicated the extent to which they used five different strategies: visual, spatial, verbal, semantic, and sensorimotor. Results revealed that individuals with aphantasia and typical imagery performed similarly to each other across all task difficulty levels. Individuals with typical imagery dominantly used visuospatial strategies, but surprisingly, individuals with aphantasia overwhelmingly preferred the use of non-visual spatial and sensorimotor strategies over verbal strategies. These results suggest that non-visual spatial and sensorimotor strategies can be adopted in visual working memory tasks and these strategies are equally effective as visuospatial strategies. This calls for a rethinking of the "visual" versus "verbal" dichotomy, and provides evidence for the use of other non-visual mental representations in working memory tasks.

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.

Phantasia, aphantasia, and hyperphantasia: Empirical data and conceptual considerations

Within the past decade, the term "phantasia" has been increasingly used to describe the human capacity, faculty, or power of visual mental imagery, with extremes of imagery vividness characterised as "aphantasia" and "hyperphantasia". A substantial volume of empirical research addressing these constructs has now been published, including attempts to find inductive correlates of behaviourally defined aphantasia, for example using research questionnaires and functional magnetic resonance imaging. Mental imagery has long been noted as a source of conceptual confusions but no specific conceptual analysis of the new formulation of phantasia, aphantasia, and hyperphantasia has been undertaken hitherto. We offer some conceptual considerations on phantasia, noting the ongoing confusion of perceptual with mental images, and the ubiquitous use of unvalidated subjective assessment instruments such as the Vividness of Visual Imagery Questionnaire (VVIQ) in diagnosis and assessment, development of which was predicated on these conceptual confusions. We offer some suggestions for a conceptual framework for future empirical studies in this field, circumventing these conceptual confusions.

Metacognitive Awareness and the Subjective Experience of Remembering in Aphantasia

Individuals with aphantasia, a nonclinical condition typically characterized by mental imagery deficits, often report reduced episodic memory. However, findings have hitherto rested largely on subjective self-reports, with few studies experimentally investigating both objective and subjective aspects of episodic memory in aphantasia. In this study, we tested both aspects of remembering in aphantasic individuals using a custom 3-D object and spatial memory task that manipulated visuospatial perspective, which is considered to be a key factor determining the subjective experience of remembering. Objective and subjective measures of memory performance were taken for both object and spatial memory features under different perspective conditions. Surprisingly, aphantasic participants were found to be unimpaired on all objective memory measures, including those for object memory features, despite reporting weaker overall mental imagery experience and lower subjective vividness ratings on the memory task. These results add to newly emerging evidence that aphantasia is a heterogenous condition, where some aphantasic individuals may lack metacognitive awareness of mental imagery rather than mental imagery itself. In addition, we found that both participant groups remembered object memory features with greater precision when encoded and retrieved in the first person versus third person, suggesting a first-person perspective might facilitate subjective memory reliving by enhancing the representational quality of scene contents.

Cognitive strengths in neurodevelopmental disorders, conditions and differences: A critical review

Neurodevelopmental disorders are traditionally characterised by a range of associated cognitive impairments in, for example, sensory processing, facial recognition, visual imagery, attention, and coordination. In this critical review, we propose a major reframing, highlighting the variety of unique cognitive strengths that people with neurodevelopmental differences can exhibit. These include enhanced visual perception, strong spatial, auditory, and semantic memory, superior empathy and theory of mind, along with higher levels of divergent thinking. Whilst we acknowledge the heterogeneity of cognitive profiles in neurodevelopmental conditions, we present a more encouraging and affirmative perspective of these groups, contrasting with the predominant, deficit-based position prevalent throughout both cognitive and neuropsychological research. In addition, we provide a theoretical basis and rationale for these cognitive strengths, arguing for the critical role of hereditability, behavioural adaptation, neuronal-recycling, and we draw on psychopharmacological and social explanations. We present a table of potential strengths across conditions and invite researchers to systematically investigate these in their future work. This should help reduce the stigma around neurodiversity, instead promoting greater social inclusion and significant societal benefits.

Giftedness and atypical sexual differentiation: enhanced perceptual functioning through estrogen deficiency instead of androgen excess

Syndromic autism spectrum conditions (ASC), such as Klinefelter syndrome, also manifest hypogonadism. Compared to the popular Extreme Male Brain theory, the Enhanced Perceptual Functioning model explains the connection between ASC, savant traits, and giftedness more seamlessly, and their co-emergence with atypical sexual differentiation. Overexcitability of primary sensory inputs generates a relative enhancement of local to global processing of stimuli, hindering the abstraction of communication signals, in contrast to the extraordinary local information processing skills in some individuals. Weaker inhibitory function through gamma-aminobutyric acid type A (GABAA) receptors and the atypicality of synapse formation lead to this difference, and the formation of unique neural circuits that process external information. Additionally, deficiency in monitoring inner sensory information leads to alexithymia (inability to distinguish one's own emotions), which can be caused by hypoactivity of estrogen and oxytocin in the interoceptive neural circuits, comprising the anterior insular and cingulate gyri. These areas are also part of the Salience Network, which switches between the Central Executive Network for external tasks and the Default Mode Network for self-referential mind wandering. Exploring the possibility that estrogen deficiency since early development interrupts GABA shift, causing sensory processing atypicality, it helps to evaluate the co-occurrence of ASC with attention deficit hyperactivity disorder, dyslexia, and schizophrenia based on phenotypic and physiological bases. It also provides clues for understanding the common underpinnings of these neurodevelopmental disorders and gifted populations.

Aphantasia and hyperphantasia: exploring imagery vividness extremes

The vividness of imagery varies between individuals. However, the existence of people in whom conscious, wakeful imagery is markedly reduced, or absent entirely, was neglected by psychology until the recent coinage of 'aphantasia' to describe this phenomenon. 'Hyperphantasia' denotes the converse - imagery whose vividness rivals perceptual experience. Around 1% and 3% of the population experience extreme aphantasia and hyperphantasia, respectively. Aphantasia runs in families, often affects imagery across several sense modalities, and is variably associated with reduced autobiographical memory, face recognition difficulty, and autism. Visual dreaming is often preserved. Subtypes of extreme imagery appear to be likely but are not yet well defined. Initial results suggest that alterations in connectivity between the frontoparietal and visual networks may provide the neural substrate for visual imagery extremes.

Deep Aphantasia: a visual brain with minimal influence from priors or inhibitory feedback?

The authors are both self-described congenital aphantasics, who feel they have never been able to have volitional imagined visual experiences during their waking lives. In addition, Loren has atypical experiences of a number of visual phenomena that involve an extrapolation or integration of visual information across space. In this perspective, we describe Loren's atypical experiences of a number of visual phenomena, and we suggest these ensue because her visual experiences are not strongly shaped by inhibitory feedback or by prior expectations. We describe Loren as having Deep Aphantasia, and Derek as shallow, as for both a paucity of feedback might prevent the generation of imagined visual experiences, but for Loren this additionally seems to disrupt activity at a sufficiently early locus to cause atypical experiences of actual visual inputs. Our purpose in describing these subjective experiences is to alert others to the possibility of there being sub-classes of congenital aphantasia, one of which-Deep Aphantasia, would be characterized by atypical experiences of actual visual inputs.

Explicit and implicit motor simulations are impaired in individuals with aphantasia

Individuals with aphantasia report having difficulties or an inability to generate visual images of objects or events. So far, there is no evidence showing that this condition also impacts the motor system and the generation of motor simulations. We probed the neurophysiological marker of aphantasia during explicit and implicit forms of motor simulation, i.e. motor imagery and action observation, respectively. We tested a group of individuals without any reported imagery deficits (phantasics) as well as a group of individuals self-reporting the inability to mentally simulate images or movements (aphantasics). We instructed the participants to explicitly imagine a maximal pinch movement in the visual and kinaesthetic modalities and to observe a video showing a pinch movement. By means of transcranial magnetic stimulation, we triggered motor-evoked potentials in the target right index finger. As expected, the amplitude of motor-evoked potentials, a marker of corticospinal excitability, increased for phantasics during kinaesthetic motor imagery and action observation relative to rest but not during visual motor imagery. Interestingly, the amplitude of motor-evoked potentials did not increase in any of the conditions for the group of aphantasics. This result provides neurophysiological evidence that individuals living with aphantasia have a real deficit in activating the motor system during motor simulations.

A novel model of divergent predictive perception

Predictive processing theories state that our subjective experience of reality is shaped by a balance of expectations based on previous knowledge about the world (i.e. priors) and confidence in sensory input from the environment. Divergent experiences (e.g. hallucinations and synaesthesia) are likely to occur when there is an imbalance between one's reliance on priors and sensory input. In a novel theoretical model, inspired by both predictive processing and psychological principles, we propose that predictable divergent experiences are associated with natural or environmentally induced prior/sensory imbalances: inappropriately strong or inflexible (i.e. maladaptive) high-level priors (beliefs) combined with low sensory confidence can result in reality discrimination issues, a characteristic of psychosis; maladaptive low-level priors (sensory expectations) combined with high sensory confidence can result in atypical sensory sensitivities and persistent divergent percepts, a characteristic of synaesthesia. Crucially, we propose that whether different divergent experiences manifest with dominantly sensory (e.g. hallucinations) or nonsensory characteristics (e.g. delusions) depends on mental imagery ability, which is a spectrum from aphantasia (absent or weak imagery) to hyperphantasia (extremely vivid imagery). We theorize that imagery is critically involved in shaping the sensory richness of divergent perceptual experience. In sum, to predict a range of divergent perceptual experiences in both clinical and general populations, three factors must be accounted for: a maladaptive use of priors, individual level of confidence in sensory input, and mental imagery ability. These ideas can be expressed formally using nonparametric regression modeling. We provide evidence for our theory from previous work and deliver predictions for future research.

The role of dopamine in visual imagery-An experimental pharmacological study

Mental imagery enables people to simulate experiences in their minds without the presence of an external stimulus. The underlying biochemical mechanisms are poorly understood but there is vague evidence that dopamine may play a significant role. A better understanding at the biochemical level could help to unravel the mechanisms of mental imagery and related phenomena such as aphantasia (= lack of voluntary mental imagery), but also opens up possibilities for interventions to enhance or restore mental imagery. To test the hypothesis that acute dopamine depletion leads to a decrease in the strength of mental imagery, N = 22 male participants will be administered an amino acid mixture containing branched-chain amino acids (BCAAs) and tryptophan (TRP) to transiently reduce dopamine synthesis and further N = 22 male participants will receive a placebo. Plasma prolactin (PRL) levels are determined as a peripheral marker of brain dopamine function. The strength of mental imagery will be measured before and after ingestion of the BCAA/TRP mixture using the method of mental imagery priming. Additional exploratory analyses will use genetic data to investigate possible effects of variations on dopaminergic gene loci (e.g., DAT1) on dopamine levels and strength of mental imagery. The results show […].

Mental imagery and visual attentional templates: A dissociation

There is a growing interest in the relationship between mental images and attentional templates as both are considered pictorial representations that involve similar neural mechanisms. Here, we investigated the role of mental imagery in the automatic implementation of attentional templates and their effect on involuntary attention. We developed a novel version of the contingent capture paradigm designed to encourage the generation of a new template on each trial and measure contingent spatial capture by a template-matching visual feature (color). Participants were required to search at four different locations for a specific object indicated at the start of each trial. Immediately prior to the search display, color cues were presented surrounding the potential target locations, one of which matched the target color (e.g., red for strawberry). Across three experiments, our task induced a robust contingent capture effect, reflected by faster responses when the target appeared in the location previously occupied by the target-matching cue. Contrary to our predictions, this effect remained consistent regardless of self-reported individual differences in visual mental imagery (Experiment 1, N = 216) or trial-by-trial variation of voluntary imagery vividness (Experiment 2, N = 121). Moreover, contingent capture was observed even among aphantasic participants, who report no imagery (Experiment 3, N = 91). The magnitude of the effect was not reduced in aphantasics compared to a control sample of non-aphantasics, although the two groups reported substantial differences in their search strategy and exhibited differences in overall speed and accuracy. Our results hence establish a dissociation between the generation and implementation of attentional templates for a visual feature (color) and subjectively experienced imagery.

Aphantasia within the framework of neurodivergence: Some preliminary data and the curse of the confidence gap

Aphantasia is a neurocognitive phenomenon affecting voluntary visual imagery, such that it is either entirely absent, or markedly impaired. Using both the social and medical models of disability, this article discusses the extent to which aphantasia can be understood as a disorder or just a form of neutral neurodivergence, given that imagery plays a central role in thinking and memory for most other people. Preliminary school performance data are presented, showing that low imagery does not necessarily complicate life, especially given compensatory strategies and low societal barriers. In addition, we discuss the consequences of labelling aphantasia a disorder with regard to self- and public stigma, and we provide further data regarding a confidence gap, by which aphantasics perceive themselves as performing worse than they objectively do. We conclude that aphantasia should be understood as neutral neurodivergence and that labelling it a disorder is not only wrong, but potentially harmful.

The role of visual imagery in face recognition and the construction of facial composites. Evidence from Aphantasia

People with aphantasia have a markedly impaired ability to form visual images in the mind's eye. Here, by testing people with and without aphantasia, we examine the relationship between visual imagery and face processing. We show that aphantasics have weaker face recognition than people with visual imagery, using both self-report (Prosopagnosia Index) and behavioural measures (Cambridge Face Memory Test). However, aphantasics nonetheless have a fully intact ability to construct facial composites from memory (i.e., composites produced using EFIT6 by aphantasics and imagers were rated as equally accurate in terms of their resemblance to a target face). Additionally, we show that aphantasics were less able than imagers to see the resemblance between composites and a target face, suggestive of potential issues with face matching (perception). Finally, we show that holistic and featural methods of composite construction using EFIT6 produce equally accurate composites. Our results suggest that face recognition, but not face composite construction, is facilitated by the ability to represent visual properties as 'pictures in the mind'. Our findings have implications for the study of aphantasia, and also for forensic settings, where face composite systems are commonly used to aid criminal investigations.

No increased prevalence of prosopagnosia in aphantasia: Visual recognition deficits are small and not restricted to faces

Aphantasia and prosopagnosia are both rare conditions with impairments in visual cognition. While prosopagnosia refers to a face recognition deficit, aphantasics exhibit a lack of mental imagery. Current object recognition theories propose an interplay of perception and mental representations, making an association between recognition performance and visual imagery plausible. While the literature assumes a link between aphantasia and prosopagnosia, other impairments in aphantasia have been shown to be rather global. Therefore, we assumed that aphantasics do not solely exhibit impairments in face recognition but rather in general visual recognition performance, probably moderated by stimulus complexity. To test this hypothesis, 65 aphantasics were compared to 55 controls in a face recognition task, the Cambridge Face Memory Test, and a corresponding object recognition task, the Cambridge Car Memory Test. In both tasks, aphantasics performed worse than controls, indicating mild recognition deficits without face-specificity. Additional correlations between imagery vividness and performance in both tasks were found, suggesting that visual imagery influences visual recognition not only in imagery extremes. Stimulus complexity produced the expected moderation effect but only for the whole imagery-spectrum and only with face stimuli. Overall, the results imply that aphantasia is linked to a general but mild deficit in visual recognition.

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.

No general pathological significance of aphantasia: An evaluation based on criteria for mental disorders

As awareness of the phenomenon of aphantasia (= lack of voluntary imagery) has increased in recent years, many psychotherapists ponder its clinical implications. The present study investigates whether aphantasia meets the criteria for mental disorders, i.e. statistical rarity, impairment in activities of daily living, violation of social norms and inappropriate behavior and personal distress. Prevalence of aphantasia was determined meta-analytically based on 3,543 participants. An international sample of 156 participants with aphantasia (58.3% male; M_age  = 35.23) and 131 controls (65.6% male; M_age  = 28.88) was assessed with the Reading the Mind in the Eyes Test, the Questionnaire for the Assessment of Everyday Memory Performance and the Aphantasia Distress Questionnaire, as well as measures of depression, anxiety and well-being. The prevalence of aphantasia was estimated at 3.5 to 4.8%. Participants with aphantasia scored significantly lower than controls on every day and autobiographical memory, but not on theory of mind. A subgroup of 34.7% of participants with aphantasia reported distress significantly associated with lower well-being and high levels of anxiety and depression. The level of distress increased with poorer performance in autobiographical memory and theory of mind. Although aphantasia meets the criterion of statistical rarity, the impact on activities of daily living and personal distress is too weak to justify a classification as a mental disorder. In a subgroup, however, distress can reach clinically relevant levels. In individual cases, it is therefore advisable to conduct a psychological assessment, for example by means of the Aphantasia Distress Questionnaire.

Predictive processing and perception: What does imagining have to do with it?

Predictive processing (PP) accounts of perception are unique not merely in that they postulate a unity between perception and imagination, but in claiming that (i) perception should be conceptualised in terms of imagination and (ii) the two involve an identity of neural implementation. This paper argues against these claims, on both conceptual and empirical grounds. Conceptually, the manner in which PP theorists link perception and imagination belies an impoverished account of imagery as cloistered from the external world in its intentionality, akin to a virtual reality, as well as endogenously generated. Yet this ignores a whole class of imagery whose intentionality is directed on the actual environment-projected mental imagery-and also ignores the fact that imagery may be triggered crossmodally in a bottom-up, stimulus-driven way. Empirically, claiming that imagery and perception share neural circuitry ignores relevant clinical results in this area. These evidence substantial perception/imagery neural dissociations, most notably in the case of aphantasia. Taken together, the arguments here suggest that PP theorists should substantially temper, if not outright abandon, their claim to a perception/imagination unity.

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

Aphantasia is a condition characterized by a deficit of mental imagery. Since several psychopathologies are partially maintained by mental imagery, it may be illuminating to consider the condition against the background of psychological disorder. After outlining current findings and hypotheses regarding aphantasia and psychopathology, this paper suggests that some support for defining aphantasia as a lack of voluntary imagery may be found here. The paper then outlines potentially fruitful directions for future research into aphantasia in general and its relation to psychopathology in particular, including rethinking use of the SUIS to measure involuntary imagery, whether aphantasia offers protection against addiction, and whether hyperphantasia is a potential risk factor for maladaptive daydreaming, among others.

Attention, flexibility, and imagery in misophonia: Does attention exacerbate everyday disliking of sound?

INTRODUCTION

Misophonia is an unusually strong aversion to everyday sounds, such as chewing, crunching, or breathing. Here, we ask whether misophonia might be tied to an unusual profile of attention (and related traits), which serves to substantially heighten an otherwise everyday disliking of sounds.

METHODS

In Study 1, we tested 136 misophonics and 203 non-misophonics on self-report measures of attention to detail, cognitive inflexibility, and auditory imagery, as well as collecting details about their misophonia. In Study 2, we administered the Embedded Figures task to 20 misophonics and 36 non-misophonics.

RESULTS

We first showed that the degree to which sounds trigger misophonia reflects the pattern by which they are (more mildly) disliked by everyone. This suggests that misophonia is scaffolded onto existing mechanisms rather than qualitatively different ones. Compared to non-misophonics, we also found that misophonics self-reported greater attention to detail, cognitive inflexibility, and auditory imagery. As their symptoms worsen, they also become more accurate in an attentional task (Embedded Figures).

CONCLUSIONS

Our findings provide a better understanding of misophonia and support the hypothesis that dispositional traits of attention to detail may be key to elevating everyday disliking of sound into the more troubling aversions of misophonia.

Exploratory study on the use of HMD virtual reality to investigate individual differences in visual processing styles

Purpose

Global and local processing is part of human perceptual organisation, where global processing helps extract the “gist” of the visual information and local processing helps perceive the details. Individual differences in these two types of visual processing have been found in autism and ADHD (Attention-Deficit Hyperactivity Disorder). Virtual reality (VR) has become a more available method of research in the last few decades. No previous research has investigated perceptual differences using this technology.

Design/methodology/approach

The objective of the research is to threefold: (1) identify if there is association between ADHD and autistic traits and the performance on the Rey-Osterrieth complex figure (ROCF) task, (2) investigate practical effects of using VR drawing tools for research on perceptual experiences and (3) explore any perceptual differences brought out by the three-dimensional nature of the VR. The standard ROCF test was used as a baseline task to investigate the practical utility of using VR as an experimental platform. A total of 94 participants were tested.

Findings

Attention-to-detail, attention switching and imagination subscales of autism quotient (AQ) questionnaire were found to be predictors of organisational ROCF scores, whereas only the attention-to-detail subscale was predictive of perceptual ROCF scores.

Originality/value

The current study is an example of how classic psychological paradigms can be transferred into the virtual world. Further investigation of the distinct individual preferences in drawing tasks in VR could lead to a better understanding of individual differences in the processing of visuospatial information.

The prevalence of aphantasia (imagery weakness) in the general population

Visual mental imagery is the ability to create a quasi-perceptual visual picture in the mind's eye. For people with the rare trait of aphantasia, this ability is entirely absent or markedly impaired. Here, we aim to clarify the prevalence of aphantasia in the general population, while overcoming limitations of previous research (e.g., recruitment biases). In Experiment 1, we screened a cohort of undergraduate students (n502) using the Vividness of Visual Imagery Questionnaire (Marks, 1973) and found that 4.2% had aphantasia. To establish the reliability of our estimate, we then screened a new sample of people (n502) at an online crowdsourcing marketplace, again finding that approximately four percent (3.6%) had aphantasia. Overall, our combined prevalence from over a thousand people of 3.9% - which shows no gender bias - provides a useful index for how commonly aphantasia occurs, based on measures and diagnostic thresholds in line with contemporary aphantasia literature.

What is the Link Between Mental Imagery and Sensory Sensitivity? Insights from Aphantasia

People with aphantasia have impoverished visual imagery so struggle to form mental pictures in the mind's eye. By testing people with and without aphantasia, we investigate the relationship between sensory imagery and sensory sensitivity (i.e., hyper- or hypo-reactivity to incoming signals through the sense organs). In Experiment 1 we first show that people with aphantasia report impaired imagery across multiple domains (e.g., olfactory, gustatory etc.) rather than simply vision. Importantly, we also show that imagery is related to sensory sensitivity: aphantasics reported not only lower imagery, but also lower sensory sensitivity. In Experiment 2, we showed a similar relationship between imagery and sensitivity in the general population. Finally, in Experiment 3 we found behavioural corroboration in a Pattern Glare Task, in which aphantasics experienced less visual discomfort and fewer visual distortions typically associated with sensory sensitivity. Our results suggest for the very first time that sensory imagery and sensory sensitivity are related, and that aphantasics are characterised by both lower imagery, and lower sensitivity. Our results also suggest that aphantasia (absence of visual imagery) may be more accurately defined as a subtype of a broader imagery deficit we name dysikonesia, in which weak or absent imagery occurs across multiple senses.

The Ganzflicker experience: High probability of seeing vivid and complex pseudo-hallucinations with imagery but not aphantasia

There are considerable individual differences in visual mental imagery ability across the general population, including a "blind mind's eye", or aphantasia. Recent studies have shown that imagery is linked to differences in perception in the healthy population, and clinical work has found a connection between imagery and hallucinatory experiences in neurological disorders. However, whether imagery ability is associated with anomalous perception-including hallucinations-in the general population remains unclear. In the current study, we explored the relationship between imagery ability and the anomalous perception of pseudo-hallucinations (PH) using rhythmic flicker stimulation ("Ganzflicker"). Specifically, we investigated whether the ability to generate voluntary imagery is associated with susceptibility to flicker-induced PH. We additionally explored individual differences in observed features of PH. We recruited a sample of people with aphantasia (aphants) and imagery (imagers) to view a constant red-and-black flicker for approximately 10 min. We found that imagers were more susceptible to PH, and saw more complex and vivid PH, compared to aphants. This study provides the first evidence that the ability to generate visual imagery increases the likelihood of experiencing complex and vivid anomalous percepts.

Behavioral and Neural Signatures of Visual Imagery Vividness Extremes: Aphantasia versus Hyperphantasia

Although Galton recognized in the 1880s that some individuals lack visual imagery, this phenomenon was mostly neglected over the following century. We recently coined the terms "aphantasia" and "hyperphantasia" to describe visual imagery vividness extremes, unlocking a sustained surge of public interest. Aphantasia is associated with subjective impairment of face recognition and autobiographical memory. Here we report the first systematic, wide-ranging neuropsychological and brain imaging study of people with aphantasia (n = 24), hyperphantasia (n = 25), and midrange imagery vividness (n = 20). Despite equivalent performance on standard memory tests, marked group differences were measured in autobiographical memory and imagination, participants with hyperphantasia outperforming controls who outperformed participants with aphantasia. Face recognition difficulties and autistic spectrum traits were reported more commonly in aphantasia. The Revised NEO Personality Inventory highlighted reduced extraversion in the aphantasia group and increased openness in the hyperphantasia group. Resting state fMRI revealed stronger connectivity between prefrontal cortices and the visual network among hyperphantasic than aphantasic participants. In an active fMRI paradigm, there was greater anterior parietal activation among hyperphantasic and control than aphantasic participants when comparing visualization of famous faces and places with perception. These behavioral and neural signatures of visual imagery vividness extremes validate and illuminate this significant but neglected dimension of individual difference.