Aphantasia Research

Evolving library of aphantasia research. Discover the science behind extreme imagination, aphantasia and hyperphantasia. Share the latest knowledge.

Imageless imagery in aphantasia: decoding non-sensory imagery in aphantasia
Meng, M., Chang, S., Zhang, X., & Pearson, J. (2023). Imageless imagery in aphantasia: decoding non-sensory imagery in aphantasia. doi:10.21203/rs.3.rs-3162223/v1
The research delves into the workings of the early visual cortex, a part of the brain associated with visual experiences, including the ability to visualize images in our minds. A unique group of individuals, known as those with "aphantasia," cannot form mental images at all. The study aimed to understand what happens in the brains of these individuals when they attempt to visualize. Using advanced brain imaging techniques, the researchers observed the activity in the primary visual cortex during attempts at mental imagery. In people without aphantasia, this part of the brain showed patterns that matched their visual experiences. However, for those with aphantasia, the brain activity was different and couldn't be matched with typical visual perceptions. Additionally, when these individuals were exposed to visual stimuli, their brain responses were weaker compared to those without aphantasia. In essence, the study found that even though people with aphantasia can't visualize, there's still some form of representation in their visual cortex. However, this representation might be less detailed or different from the usual sensory information. This discovery challenges the traditional belief that activity in the primary visual cortex always corresponds to typical visual experiences.
Feedback signals in visual cortex during episodic and schematic memory retrieval and their potential implications for aphantasia
Bergmann, J., & Ortiz-Tudela, J. (2023). Feedback signals in visual cortex during episodic and schematic memory retrieval and their potential implications for aphantasia. Neuroscience & Biobehavioral Reviews, 152, 105335. https://doi.org/10.1016/j.neubiorev.2023.105335
This scientific paper is about memory and vision. The researchers explain how your brain processes memories and what you see. The two main types of memory are episodic memory, which is the memory of specific events in a place and time, and schematic memory, which is your brain's general knowledge about the world. The scientists found that when it comes to visual processing, or how your brain understands what your eyes see, these two types of memory work a bit differently. Episodic memory can affect the earliest stages of visual processing, while schematic memory only influences intermediate levels. They also discuss the idea that different areas of your brain might be involved in retrieving these two types of memories. Episodic memories are processed in both the regions of the brain that deal with recognizing objects ('what' areas) and understanding their location in space ('where' areas). In contrast, schematic memories are mainly processed in the 'where' areas of the brain. Lastly, the paper talks about a condition called aphantasia, where people can't create pictures in their heads or visualize things. People with aphantasia have problems with their episodic memory, but their schematic memory is not as affected. The researchers think this isn't because their episodic memory is faulty, but because these individuals can't process detailed visual information about objects from memory. This could offer new ways to understand and study aphantasia.
Measuring imagery strength in schizophrenia: no evidence of enhanced mental imagery priming
Wagner, S., & Monzel, M. (2023). Measuring imagery strength in schizophrenia: no evidence of enhanced mental imagery priming. Brain and Behavior, e3146. doi:10.1002/brb3.3146
This study aimed to explore the relationship between visual imagery, schizophrenia, and the occurrence of hallucinations. The researchers compared a group of 16 individuals with schizophrenia to a group of 44 individuals without the condition. They used questionnaires and a visual imagery task to measure the vividness of visual imagery, and the Launay-Slade Hallucination Scale to assess the occurrence of hallucinations.The results revealed that participants with schizophrenia reported more hallucinatory experiences compared to those without schizophrenia. However, surprisingly, there were no significant differences between the two groups in terms of the vividness of visual imagery as measured by both the questionnaire and the visual imagery task. Interestingly, a positive correlation was found between the vividness of visual imagery measured by the questionnaire and the visual imagery task. This indicates that the measurement tools used were reliable in assessing visual imagery. These findings suggest that the association between mental imagery vividness and schizophrenia may be more complex than previously thought. While individuals with schizophrenia experience more hallucinations, their visual imagery vividness does not appear to be enhanced. This suggests that other aspects of mental imagery may be more relevant in understanding the relationship between mental imagery and schizophrenia.
Subjective signal strength distinguishes reality from imagination
Dijkstra, N., & Fleming, S. M. (2023). Subjective signal strength distinguishes reality from imagination. Nature Communications, 14(1), 1627. doi:10.1038/s41467-023-37322-1
This research explores how our brain distinguishes between real and imagined experiences. The study shows that the line between reality and imagination is blurred, with imagined and perceived signals get mixed together. The researchers used a combination of psychophysics, computational modeling, and neuroimaging to investigate this phenomenon. They found that judgments of reality are based on whether the mixed signal, which includes both imagined and perceived elements, is strong enough to cross a reality threshold. Interestingly, when the virtual or imagined signals are strong enough, they become subjectively indistinguishable from reality. The study also suggests that the frontal cortex, responsible for emotions and memories, may play a role in regulating the strength of the mental image signal. Further research is needed to understand the factors that determine the vividness of mental imagery and the distinction between the imagery signal and the reality threshold. In future studies, it would be intriguing to investigate the reality thresholds of individuals with hyperphantasia, an extremely vivid imagination and the experiences of individuals with aphantasia, who have difficulty consciously conjuring mental images. It could shed light on how visual imagery impacts our perception of reality.