Related Experiment Video
Updated: Feb 28, 2026

Visualization Method for Proprioceptive Drift on a 2D Plane Using Support Vector Machine
Published on: October 27, 2016
Seeing without eyes: Relation between visual mental imagery and visual hallucinations
Massimiliano Panigutti1, Giulia Bechi Gabrielli2, Desirée Conti1
1Cognitive and Motor Rehabilitation and Neuroimaging Unit, IRCCS Fondazione Santa Lucia, Rome, Italy; Department of Psychology, Sapienza University of Rome, Rome, Italy.
Abstract:
Visual mental imagery (VMI) refers to the ability to "see with the mind's eye", in the absence of adequate sensory input, while visual hallucinations (VH) involve perceiving stimuli in their absence. This review investigates the relationship between VMI and VH across neurodegenerative and psychiatric conditions, focusing on Parkinson's disease (PD), Alzheimer's disease (AD), Dementia with Lewy bodies (DLB), and schizophrenia (SCZ). A relationship between VMI and VH was identified, with greater VMI vividness associated with increased VH occurrence in all conditions, except for DLB, for which no studies were found. Moreover, PD and SCZ patients with VH showed reality monitoring deficits. Neuroimaging studies highlighted the role of temporo-occipital regions in both phenomena, with additional disruptions in frontal connectivity in SCZ. Furthermore, patients with VH have stronger VMI, suggesting a prevalence of top-down processes leading to generate vivid internal images, which might be due to a condition of hyper-functioning of visual associative areas. In psychiatric conditions, reality monitoring deficits and thought disorder exacerbate this tendency, leading to the misattribution of bizarre internal contents to external events.
More Related Videos
05:36Central and Divided Visual Field Presentation of Emotional Images to Measure Hemispheric Differences in Motivated Attention
Published on: November 16, 2017
11:29Real-time Video Projection in an MRI for Characterization of Neural Correlates Associated with Mirror Therapy for Phantom Limb Pain
Published on: April 20, 2019
Related Concept Videos
Positive Symptoms Schizophrenia: Hallucinations and Delusions
Hallucinations
Hallucinations in...
Visual Agnosia
Hallucinogens and Psychedelics
Marijuana, derived from the dried leaves and flowers of the hemp plant, contains...
Vision
Depth Perception and Spatial Vision
Visual System
Once through the pupil, the light passes through the lens, a...