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Mental Imagery is a topic of longstanding and widespread scientific interest. Individual studies have typically focused on a single modality (e.g. Motor, Visual, Auditory) of Mental Imagery. Relatively little work has considered directly comparing and contrasting the brain networks associated with these different modalities of Imagery. The present study integrates data from 439 neuroimaging experiments to identify both modality-specific and shared neural networks involved in Mental Imagery. Comparing the networks involved in Motor, Visual, and Auditory Imagery identified a pattern whereby each form of Imagery preferentially recruited 'higher level' associative brain regions involved in the associated 'real' experience. Results also indicate significant overlap in a left-lateralized network including the pre-supplementary motor area, ventral premotor cortex and inferior parietal lobule. This pattern of results supports the existence of a 'core' network that supports the attentional, spatial, and decision-making demands of Mental Imagery. Together these results offer new insights into the brain networks underlying human imagination.

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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.

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Sensorimotor synchronization (SMS) is the temporal coordination of motor movements with external or imagined stimuli. Finger-tapping studies indicate better SMS performance with auditory or tactile stimuli compared to visual. However, SMS with a visual rhythm can be improved by enriching stimulus properties (e.g., spatiotemporal content) or individual differences (e.g., one's vividness of auditory imagery). We previously showed that higher self-reported vividness of auditory imagery led to more consistent synchronization-continuation performance when participants continued without a guiding visual rhythm. Here, we examined the contribution of imagery to the SMS performance of proficient imagers, including an auditory or visual distractor task during the continuation phase. While the visual distractor task had minimal effect, SMS consistency was significantly worse when the auditory distractor task was present. Our electroencephalography analysis revealed beat-related neural entrainment, only when the visual or auditory distractor tasks were present. During continuation with the auditory distractor task, the neural entrainment showed an occipital electrode distribution, suggesting the involvement of visual imagery. Unique to SMS continuation with the auditory distractor task, we found neural and sub-vocal (measured with electromyography) entrainment at the three-beat pattern frequency. In this most difficult condition, proficient imagers employed both beat- and pattern-related imagery strategies. However, this combination was insufficient to restore SMS consistency to that observed with visual or no distractor task. Our results suggest that proficient imagers effectively utilized beat-related imagery in one modality when imagery in another modality was limited.

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BACKGROUND: This study aims to explore the efficacy of Relaxation Response Meditation Training (RRMT) on elderly individuals with different levels of vividness of visual imagery. METHODS: In this randomized controlled, double-blind, multi-center clinical trial, we recruited a total of 136 elderly individuals who were over 60 years with nonorganic sleep disorders to participate in a 4-week RRMT intervention from October 2020 to October 2022. The intervention occurred twice a week, totaling eight times. These individuals were divided into high and low groups based on the vividness of visual imagery, and then randomly assigned to either the control or intervention groups, as follows: low-visualizers intervention group (LI group); low-visualizers control group (LC group); high-visualizers intervention group (HI group); high-visualizers control group (HC group). Their social and psychological parameters were assessed before and after the intervention by the Pittsburgh Sleep Quality Index (PSQI), the Revised Piper's fatigue scale (RPFS), General well-being scale (GWB), and Satisfaction rating. The alpha waves of patients were also collected through electroencephalogram to assess their level of relaxation. RESULTS: Compared to the LI group, the HI group had a greater reduction rate in the PSQI score [25.2 % (18.8 % to 31.7 %), P < 0∙001], shorter sleep latency (P = 0.001), lower frequency of sleep medication (P < 0.001), lower PSQI scores (P < 0.001), and higher GWB scores (P < 0.001). There were significant differences in all indicators in the HI group vs. HC group and in the LI group vs. LC group. In the first five relaxation training sessions, there was no statistically significant difference in the proportion of α waves between the LI group and the LC group; however, from the sixth session onward, we observed a statistically significant difference (t = 2.86, P = 0.019)，while The HI group and HC group showing significant differences in the first relaxation training session (t = 4.464, P < 0.001). There was a statistically significant difference in subjective satisfaction between the intervention group and the control group (x2 = 49.605, P < 0.001). CONCLUSION: In this study, we found that most elderly people benefitted from RRMT regardless of their vividness of visual imagery. However, low-visualizers experienced slower and less effective results, so these patients may benefit more from alternative approaches.

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Anticipating the behaviour of moving objects in the physical environment is essential for a wide range of daily actions. This ability is thought to rely on mental simulations and has been shown to involve frontoparietal and early visual areas. Yet, the connectivity patterns between these regions during intuitive physical inference remain largely unknown. In this study, participants underwent fMRI while performing a task requiring them to infer the parabolic trajectory of an occluded ball falling under Newtonian physics, and a control task. Building on our previous research showing that when solving the physical inference task, early visual areas encode task-specific and perception-like information about the inferred trajectory, the present study aimed to (i) identify regions that are functionally coupled with early visual areas during the physical inference task, and (ii) investigate changes in effective connectivity within this network of regions. We found that early visual areas are functionally connected to a set of parietal and premotor regions when inferring occluded trajectories. Using dynamic causal modelling, we show that predicting occluded trajectories is associated with changes in effective connectivity within a parieto-premotor network, which may drive internally generated early visual activity in a top-down fashion. These findings offer new insights into the interaction between early visual and frontoparietal regions during physical inference, contributing to our understanding of the neural mechanisms underlying the ability to predict physical outcomes.

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The pupillary light response was long considered a brainstem reflex, outside of cognitive influence. However, newer findings indicate that pupil dilation (and eye movements) can reflect content held "in mind" with working memory (WM). These findings may reshape understanding of ocular and WM mechanisms, but it is unclear whether the signals are artifactual or functional to WM. Here, we ask whether peripheral and oculomotor WM signals are sensitive to the task-relevance or "attentional state" of WM content. During eye-tracking, human participants saw both dark and bright WM stimuli, then were retroactively cued to the item that would most likely be tested. Critically, we manipulated the attentional priority among items by varying the cue reliability across blocks. We confirmed previous findings that remembering darker items is associated with larger pupils (vs. brighter), and that gaze is biased toward cued item locations. Moreover, we discovered that pupil and eye movement responses were influenced differently by WM item relevance. Feature-specific pupillary effects emerged only for highly prioritized WM items but were eliminated when cues were less reliable, and pupil effects also increased with self-reported visual imagery strength. Conversely, gaze position consistently veered toward the cued item location, regardless of cue reliability. However, biased microsaccades occurred at a higher frequency when cues were more reliable, though only during a limited post-cue time window. Therefore, peripheral sensorimotor processing is sensitive to the task-relevance or functional state of internal WM content, but pupillary and eye movement WM signals show distinct profiles. These results highlight a potential role for early visual processing in maintaining multiple WM content dimensions.NEW & NOTEWORTHY Here, we found that working memory (WM)-driven ocular inflections-feature-specific pupillary and saccadic biases-were muted for memory items that were less behaviorally relevant. This work illustrates that functionally informative goal signals may extend as early as the sensorimotor periphery, that pupil size may be under more fine-grained control than originally thought, and that ocular signals carry multiple dimensions of cognitively relevant information.

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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.

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Mental rotation tasks are frequently used as standard measures of mental imagery. However, aphantasia research has brought such use into question. Here, we assessed a large group of individuals who lack visual imagery (aphantasia) on two mental rotation tasks: a three-dimensional block-shape, and a human manikin rotation task. In both tasks, those with aphantasia had slower, but more accurate responses than controls. Both groups demonstrated classic linear increases in response time and error-rate as functions of angular disparity. In the three-dimensional block-shape rotation task, a within-group speed-accuracy trade-off was found in controls, whereas faster individuals in the aphantasia group were also more accurate. Control participants generally favoured using object-based mental rotation strategies, whereas those with aphantasia favoured analytic strategies. These results suggest that visual imagery is not crucial for successful performance in classical mental rotation tasks, as alternative strategies can be effectively utilised in the absence of holistic mental representations.

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Two experiments investigated the role of visual imagery in prospective memory (PM). In experiment 1, 140 participants completed a general knowledge quiz which included a PM task of writing a letter "X" next to any questions that referred to space. Participants either visualised themselves performing this task, verbalised an implementation intention about the task, did both, or did neither. Performance on the PM task was enhanced in both conditions involving visual imagery but not by implementation intentions alone. In experiment 2, 120 participants imagined themselves writing a letter "X" next to questions about space, or in a bizarre imagery condition imagined themselves drawing an alien next to those questions. Relative to the control condition, PM was significantly enhanced when participants imagined writing a letter "X" next to the target questions, but not by the bizarre imagery task. The findings indicate that the robust effects of imagery observed in retrospective memory also extend to PM.

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This article examines empirical associations between qualities of the imagination, mental imagery, and cognitive abilities with special reference to autism. This study is the first to explore the empirical relationships between autistic-like traits and tests of imagery differences. Imaginative impairments and distinctive sensory characteristics in individuals with autism spectrum disorder (ASD) should be reflected in their interactions with mental imagery. However, the relationship between ASD and imaging traits remains unclear. Based on the hypothesis that the degree of autistic-like traits is reflected in imagery traits, this study examined how the individual Autism Spectrum Quotient (AQ) relates to imagery ability in 250 college students. Two vividness tests and one imagery-type test were used to assess imagery ability. Scores in each imagery test were compared between the high-scoring group classified by the AQ and the rest of the participants and between the low-scoring group classified by the AQ and the other participants. This study also directly compared imagery test scores between the high- and low-scoring groups. In terms of the total AQ score, the high-scoring group exhibited lower visualization scores. Regarding AQ subscales, "imagination" had the most extensive relationship with imagery traits, with the high-scoring group (unimaginative) showing lower imagery vividness across various modalities as well as lower visualization and verbalization scores. This was followed by the "attention to detail" subscale, on which the high-scoring group (attentive to detail) showed higher vividness of visual imagery. The results of the low-scoring group exhibited, on the whole, opposite imagery tendencies to the high-scoring group. The results indicate that autistic-like traits are associated with qualities of the imagination and especially mental imagery ability.

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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.

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The inability to visualise was given the name aphantasia in 2015 by Zeman and colleagues. In 2018 we published research showing that fifteen individuals who self-identified as having aphantasia also demonstrated a lack of sensory visual imagery when undergoing the binocular rivalry imagery paradigm, suggesting more than just a metacognitive difference. Here we update these findings with over fifty participants with aphantasia and show that there is evidence for a lack of sensory imagery in aphantasia. How the binocular rivalry paradigm scores relate to the vividness of visual imagery questionnaire (VVIQ) and how aphantasia can be confirmed is discussed.

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It has been suggested that visual images are memorized across brief periods of time by vividly imagining them as if they were still there. In line with this, the contents of both working memory and visual imagery are known to be encoded already in early visual cortex. If these signals in early visual areas were indeed to reflect a combined imagery and memory code, one would predict them to be weaker for individuals with reduced visual imagery vividness. Here, we systematically investigated this question in two groups of participants. Strong and weak imagers were asked to remember images across brief delay periods. We were able to reliably reconstruct the memorized stimuli from early visual cortex during the delay. Importantly, in contrast to the prediction, the quality of reconstruction was equally accurate for both strong and weak imagers. The decodable information also closely reflected behavioral precision in both groups, suggesting it could contribute to behavioral performance, even in the extreme case of completely aphantasic individuals. Our data thus suggest that working memory signals in early visual cortex can be present even in the (near) absence of phenomenal imagery.

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The verbal overshadowing effect refers to the phenomenon that the verbal description of a past complex stimulus impairs its subsequent recognition. Theoretical explanations range from interference between different mental representations to the activation of different processing orientations or a provoked shift in the recognition criterion. In our study, 61 participants with aphantasia (= lack of mental imagery) and 70 controls participated in a verbal overshadowing paradigm. The verbal overshadowing effect did not occur in people with aphantasia, although the effect was replicated in controls. We speculate that this is either due to the lack of visual representations in people with aphantasia that verbal descriptions could interfere with, or to the absence of a shift in processing orientation during verbalisation. To rule out criterion-based explanations, further research is needed to distinguish between discriminability and response bias in people with aphantasia. Finally, data indicated that the verbal overshadowing effect may even be reversed in individuals with aphantasia, partly due to a lower memory performance in the no verbalisation condition. Effects of further variables are discussed, such as mental strategies, memory confidence, and difficulty, quantity and quality of verbalisation.

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Visual imagery, i.e., seeing in the absence of the corresponding retinal input, has been linked to visual and motor processing areas of the brain. Music listening provides an ideal vehicle for exploring the neural correlates of visual imagery because it has been shown to reliably induce a broad variety of content, ranging from abstract shapes to dynamic scenes. Forty-two participants listened with closed eyes to twenty-four excerpts of music, while a 15-channel EEG was recorded, and, after each excerpt, rated the extent to which they experienced static and dynamic visual imagery. Our results show both static and dynamic imagery to be associated with posterior alpha suppression (especially in lower alpha) early in the onset of music listening, while static imagery was associated with an additional alpha enhancement later in the listening experience. With regard to the beta band, our results demonstrate beta enhancement to static imagery, but first beta suppression before enhancement in response to dynamic imagery. We also observed a positive association, early in the listening experience, between gamma power and dynamic imagery ratings that was not present for static imagery ratings. Finally, we offer evidence that musical training may selectively drive effects found with respect to static and dynamic imagery and alpha, beta, and gamma band oscillations. Taken together, our results show the promise of using music listening as an effective stimulus for examining the neural correlates of visual imagery and its contents. Our study also highlights the relevance of future work seeking to study the temporal dynamics of music-induced visual imagery.

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The retrieval of autobiographical memories involves the construction of mental representations of past personal events. Many researchers examining the processes underlying memory retrieval argue that visual imagery plays a fundamental role. Other researchers, however, have argued that working memory is an integral component involved in memory retrieval. The goal of this study was to resolve these conflicting arguments by comparing the relative contributions of visual imagery and working memory during the retrieval of autobiographical memories in a dual-task paradigm. While following a moving dot, viewing a dynamic visual noise (DVN), or viewing a blank screen, 95 participants recalled their memories and subsequently rated them on different memory characteristics. The results suggest that inhibiting visual imagery by having participants view DVN merely delayed memory retrieval but did not affect the phenomenological quality of the memories retrieved. Taxations to the working memory by having participants follow a moving dot, on the contrary, resulted in only longer retrieval latencies and no reductions in the specificity, vividness, or the emotional intensity of the memories retrieved. Whereas the role of visual imagery during retrieval is clear, future studies could further examine the role of working memory during retrieval by administering a task that is less difficult or by recruiting a larger sample than this study. The results of this study seem to suggest that both visual imagery and working memory play a role during the retrieval of autobiographical memory, but more research needs to be conducted to determine their exact roles.

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Previous research demonstrated effects of visual imagery on search speed in visual search paradigms. However, these effects were rather small, questioning their ecological validity. Thus, our present study aimed to generalize these effects to more naturalistic material (i.e., a paradigm that allows for top-down strategies in highly complex visual search displays that include overlapping stimuli while simultaneously avoiding possibly confounding search instructions). One hundred and four participants with aphantasia (= absence of voluntary mental imagery) and 104 gender and age-matched controls were asked to find hidden objects in several hidden object pictures with search times recorded. Results showed that people with aphantasia were significantly slower than controls, even when controlling for age and general processing speed. Thus, effects of visual imagery might be strong enough to influence the perception of our real-life surroundings, probably because of the involvement of visual imagery in several top-down strategies.

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How do we know what is real and what is merely a figment of our imagination? Dijkstra and Fleming tackle this question in a recent study. In contrast to the classic Perky effect, they found that once imagery crosses a 'reality threshold', it becomes difficult to distinguish from reality.

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Previous research has established a strong link between attention and visual mental imagery, but it's remained uncertain whether attention networks influence individual differences in the vividness of visual mental imagery. In our study, we examined 140 participants, assessing the vividness of imagery using the Vividness of Visual Imagery Questionnaire in both eyes-open and eyes-closed conditions. We employed the Attention Network Test, coupled with EEG recording, to characterize three attention sub-networks: alerting, orienting, and executive control. To pinpoint the specific attentional networks associated with the vividness of visual mental imagery, we utilized latent profile analysis to categorize participants into distinct subgroups. Additionally, we constructed a regression mixture model to explore how attention networks predict different latent categories of visual imagery vividness. Our findings revealed that the efficiency of the alerting network, as indicated by the N1 component, demonstrated a positive correlation with the vividness of visual imagery. This electrophysiological evidence underscores the role of the alerting network in shaping individual differences in the vividness of visual mental imagery.

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Research into the newly-coined 'condition' of 'aphantasia', an individual difference involving the self-reported absence of voluntary visual imagery, has taken off in recent years, and more and more people are 'self-diagnosing' as aphantasic. Yet, there is no consensus on whether aphantasia should really be described as a 'condition', and there is no battery of psychometric instruments to detect or 'diagnose' aphantasia. Instead, researchers currently rely on the Vividness of Visual Imagery Questionnaire (VVIQ) to 'diagnose' aphantasia. We review here fundamental and methodological problems affecting aphantasia research stemming from an inadequate focus on how we should define aphantasia, whether aphantasia is a pathological condition, and the extensive use of VVIQ as a 'diagnostic test' for aphantasia. Firstly, we draw attention to 'literature blindness' for visual imagery research from the 1960s-1990s concerning individual differences in visual imagery vividness. Secondly, despite aphantasia being defined as a 'condition' where voluntary visual imagery is absent as indicated by the lowest score on the VVIQ, aphantasia studies inconsistently employ samples comprised of a mixture of participants with no visual imagery and low visual imagery, and we argue that this hinders the uncovering of the underlying cause of aphantasia. Thirdly, the scores used to designate the boundary between aphantasia and non-aphantasia are arbitrary and differ between studies, compromising the possibility for cross-study comparison of results. Fourthly, the problems of 'diagnosing' aphantasia are not limited to the academic sphere, as one can 'self-diagnose' online, for example by using the variant-VVIQ on the Aphantasia Network website. However, the variant-VVIQ departs from the original in ways likely to impact validity and accuracy, which could lead people to falsely believe they have been 'diagnosed' with aphantasia by a scientifically-validated measure. Fifthly, we discuss the hypothesis that people who believe they have been 'diagnosed' with aphantasia might be vulnerable to health anxiety, distress, and stigma. We conclude with a discussion about some fundamental aspects of how to classify a disorder, and suggest the need for a new psychometric measure of aphantasia.

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