Table 1.
List of structural brain alternations associated with MDD with the respective outcomes, related conditions, and frequency.
| Brain Region | Alteration | Outcome | Related conditions | Frequency | References |
|---|---|---|---|---|---|
| Whole-brain | Increased CSF volume; decreased gray matter volume | Cognitive impairments | SCZ | Uncommon | 4,93 |
| Ventricles | Enlarged lateral ventricles | Communication hindrances | AD, PD, SCZ | Common | 4,17 |
| Frontal Lobe | Reduced overall gray matter volumes; reduced orbitofrontal cortex and gyrus rectus volumes | Impaired executive functions | ADHD; BPD; CP; MDD; SCZ | Very common | 8,9 |
| Temporal Lobe | Reduced volumes of the hippocampus, right precentral gyrus, left temporal gyrus, right postcentral gyrus, left paracentral gyrus, and left posterior cingulate | Abnormal emotional responses and sensory input dysfunction | ADHD; ASD; DM; SCZ | Very Common | 4,11,13,94 |
| Pariteal lobe | Reduced gray matter volume; cortex thickening, | Decline of visual and spatial interactions | ASD; SCZ | Common | 14,15,95 |
| Occipital Lobe | Reduced gray matter volume; occipital bending; reduced pericalcarine cortex volume | Impaired processing, integration, and interpretation of vision and visual stimuli | GAD; SCZ | Uncommon | 17,24 |
| Cerebellum | Reduced volumes of the putamen, caudate, insula, and basal ganglia | Problems with balance, coordination, and fine muscle control | ASD; ADHD; SCZ | Common | 19,24,96 |
AD Alzheimer’s disease, ADHD attention deficit/hyperactivity disorder, ASD autism spectrum disorder, BPD bipolar disorder, CP chronic pain, DM dementia, GAD generalized anxiety disorder, MDD major depressive disorder, SCZ schizophrenia