Imagery and hallucination look related but aren't the same thing. This covers pseudo-hallucinations, the Ganzflicker effect, and where perception and imagination overlap.
Panigutti and colleagues · Neuroscience & Biobehavioral Reviews
This systematic review found only 11 studies on imagery and hallucinations in Parkinson's, Alzheimer's and schizophrenia, and none in Lewy body dementia. Seven reported a link and four did not, so the evidence is indecisive.
Pepin and colleagues · Consciousness and Cognition
Involuntary mental imagery is more frequent and vivid than hallucinations, though both share similar phenomenological traits. This suggests these inner experiences exist on a continuum rather than being entirely distinct phenomena.
Incekara and Blom · Frontiers in Psychology
Analysis of Carl Jung's self-reports suggests his anomalous experiences stemmed from hyperphantasia rather than a psychotic disorder. This indicates that extremely vivid imagery can cross a reality threshold and be misidentified as psychosis.
Sulfaro, Robinson and Carlson · Neuroscience of Consciousness
Researchers found that sensory input competes with mental imagery in a hierarchical neural network, preventing thoughts from dominating low-level sensory regions. This explains why mental imagery feels less vivid than real perception and how aphantasia arises from overweighted bottom-up signals.
Dijkstra and Fleming · Nature Communications
The brain distinguishes reality from imagination based on whether intermixed sensory signals cross a strength threshold. This suggests that sufficiently vivid mental imagery can become subjectively indistinguishable from actual perception.
Königsmark, Bergmann and Reeder · Cortex
People with aphantasia are significantly less likely to experience vivid or complex pseudo-hallucinations during rhythmic flicker stimulation. This suggests that the ability to generate voluntary mental imagery increases susceptibility to anomalous perceptual experiences.
Salge, Pollmann and Reeder · Psychological Research
Researchers found that higher visual imagery vividness correlates with increased pareidolia proneness in both static and dynamic noise. This suggests that vivid mental imagery can lead to more frequent misperceptions of reality.
Pearson and Westbrook · Trends in Cognitive Sciences
Researchers propose a dichotomous framework for phantom perception, distinguishing between voluntary mental imagery and involuntary experiences like illusions or synesthesia. This classification helps unify diverse sensory phenomena and provides a roadmap for studying the neural mechanisms of constructive perception.