Psychopharmacology
October 4, 2018
Baland Jalal
42 citations
Sleep paralysis involves involuntary immobility at sleep onset or offset, often with 'ghost-like' hallucinations and intense fear. This account proposes that serotonin 2A receptor (5-HT2AR) activation underlies these hallucinatory experiences, drawing parallels to serotonergic hallucinations induced by drugs like LSD and psilocybin, which are dream-like and retain insight, unlike dopaminergic hallucinations. The mechanism suggests 5-HT2AR activity generates visual hallucinations, mystical states, out-of-body experiences, and fear. The role of 5-HT2C receptors in anxiety and the orbitofrontal cortex in visual pathways is speculated. Pimavanserin, a selective 5-HT2AR inverse agonist, is proposed as a first drug to target these symptoms, implicating gene HTR2A on chromosome 13q.
Frontiers in Human Neuroscience
February 27, 2017
Baland Jalal, Vilayanur S. Ramachandran
38 citations
This opinion article argues that the concept of brain health should be expanded beyond the absence of disease to include optimal cognitive and emotional functioning across the lifespan. The authors propose a framework that integrates neuroscience, psychology, and public health to promote resilience and well-being. They suggest that lifestyle factors, such as diet, exercise, and social engagement, can enhance brain health and reduce the risk of neurodegenerative conditions. The piece calls for a shift in research and clinical practice toward proactive, preventive approaches that empower individuals to maintain brain health throughout life.
Frontiers in neurology
January 1, 2020
Baland Jalal, Ludovico Moruzzi, Andrea Zangrandi et al.
13 citations
A small pilot study tested Meditation-Relaxation (MR) therapy for sleep paralysis (SP) in ten patients with narcolepsy. Over eight weeks, the six patients receiving MR therapy showed a 50% reduction in days with SP and a 54% reduction in total SP episodes in the last month, with large within-group effect sizes. The four patients in the control group (deep breathing) did not show similar improvement. These preliminary findings provide the first proof-of-concept evidence that MR therapy may reduce frequent SP, and the authors cautiously suggest the approach might generalize to people with isolated SP.
BMC psychiatry
June 7, 2022
Paulina Wróbel-knybel, Michał Flis, Joanna Róg et al.
9 citations
Sleep paralysis affects 33.14% of Polish students, highlighting its significant prevalence in this population. Among the 2,553 analyzed participants, factors like having three or more health issues (odds ratio of 2.3) and any mental disorder (1.77) increased the likelihood of experiencing sleep paralysis. High anxiety levels (1.20), smoking (1.48), and alcohol consumption (1.52) also contributed to this risk. These findings suggest that mental health status, lifestyle choices, and physical health are critical in understanding sleep disorders like sleep paralysis among students.
Medical hypotheses
March 1, 2021
Baland Jalal
Sleep paralysis is a condition in which a person, while paralyzed, may hallucinate terrifying ghosts—often faceless shadows, but also full figures like cat-like creatures or witches. This paper proposes a neuroscientific account explaining why these hallucinations occur and why they typically appear as faceless shadows. The account focuses on the distinct computational styles of the right and left hemispheres, suggesting that ghost hallucinations and out-of-body experiences during sleep paralysis are primarily mediated by activity in key right-hemisphere regions. The visual system's economizing nature, including surface interpolation and shortcuts, is invoked to explain faceless humanoid-shadows and sensed presence. The hypothalamus and anterior cingulate may also be involved in related dissociative states. The author notes that empirical research is needed to validate this hypothesis.