Related Experiment Video
Updated: Feb 1, 2026
Highlighting and Reducing the Impact of Negative Aging Stereotypes During Older Adults' Cognitive Testing
Published on: January 24, 2020
Age-related deficits in intracortical myelination in young adults with bipolar disorder type I
Manpreet Sehmbi1, Christopher D. Rowley1, Luciano Minuzzi1
1From the Graduate Student, MiNDS Neuroscience Graduate Program, McMaster University, Hamilton, ON (Sehmbi, Rowley); the Mood Disorders Program, Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, ON (Minuzzi, Kapczinski, Frey); the Women’s Health Concerns Clinic, St. Joseph’s Healthcare, Hamilton, ON (Minuzzi, Frey); the Department of Pathology and Molecular Medicine, M. deGroote School of Medicine, McMaster University, Hamilton, ON (Kwiecien); the Department of Psychology, Neuroscience, and Behaviour, McMaster University, Hamilton, ON (Bock); and the Department of Clinical Pathomorphology, Medical University of Lublin, Poland (Kwiecien).
Background:
Previous studies have implicated white-matter-related changes in the pathophysiology of bipolar disorder. However, most of what is known is derived from in vivo subcortical white-matter imaging or postmortem studies. In this study, we investigated whole-brain intracortical myelin (ICM) content in people with bipolar disorder type I and controls.
Methods:
Between Sept. 1, 2014, and Jan. 31, 2017, we used a 3 T General Electric scanner to collect T1-weighted images in 45 people with bipolar disorder type I and 60 controls aged 17 to 45 years using an optimized sequence that was sensitive to ICM content. We analyzed images using a surfacebased approach. We used general linear models with quadratic age terms to examine the signal trajectory of ICM across the age range.
Results:
In healthy controls, the T1-weighted signal followed an inverted-U trajectory over age; in people with bipolar disorder type I, the association between ICM and age followed a flat trajectory (p < 0.05, Bonferroni corrected). Exploratory analyses showed that ICM signal intensity was associated with duration of illness, age of onset, and anticonvulsant and antipsychotic use in people with bipolar disorder type I (p < 0.05, uncorrected).
Limitations:
Because of the cross-sectional nature of the study, we were unable to comment on whether the effects were due to dysmyelination or demyelination in bipolar disorder.
Conclusion:
This foundational study is, to our knowledge, the first to show global age-related deficits in ICM maturation throughout the cortex in bipolar disorder. Considering the impact of myelination on the maintenance of neural synchrony and the integrity of neural connections, this work may help us better understand the cognitive and behavioural deficits seen in bipolar disorder.
Related Concept Videos
01:30Bipolar Disorder
01:30Attention-Deficit/Hyperactivity Disorder
Diagnostic Criteria and Symptoms
To diagnose ADHD, symptoms must manifest before age 12 and be evident across multiple settings....
01:30Pleural Disorders: Types and Brief Description
01:22Bipolar Junction Transistor
01:25Nervous Tissue: Myelin
Schwann cells begin to form myelin sheaths around axons during fetal development. They wrap around a small...
01:26Aging
Cellular Clock Theory
The cellular clock theory posits that the human lifespan is closely tied to the finite capacity of cells to divide, a phenomenon governed by telomeres, which are protective caps at the ends of...