The human brain is composed of distinct anatomical regions, each with unique cellular compositions, connectivity patterns, and functional roles. Understanding brain anatomy is fundamental to understanding how neurodegenerative diseases affect brain structure and function. [1]
The cerebral cortex is the outer layer of the brain, responsible for higher cognitive functions including: [2]
The cortex is organized into six layers (neocortex), each with distinct neuron types and connectivity patterns. Cortical layer organization is disrupted in many neurodegenerative diseases. [3]
Deep brain structures beneath the cortex involved in movement, memory, and emotion:
The brainstem controls vital functions and is an early site of pathology in several neurodegenerative diseases:
Located at the back of the brain, the cerebellum is traditionally associated with motor coordination but also plays roles in:
Each brain region has distinct cellular compositions:
| Cell Type | Primary Locations | Functions |
|---|---|---|
| Glutamatergic neurons | Cortex, hippocampus | Excitatory signaling |
| GABAergic neurons | Cortex, striatum | Inhibitory signaling |
| Dopaminergic neurons | Substantia nigra, VTA | Reward, movement |
| Cholinergic neurons | Basal forebrain, brainstem | Memory, attention |
| Astrocytes | Throughout brain | Metabolic support, homeostasis |
| Microglia | Throughout brain | Immune surveillance |
| Oligodendrocytes | White matter | Myelination |
Different neurodegenerative diseases target specific brain regions:
Alzheimer's Disease:
Frontotemporal Dementia:
Amyotrophic Lateral Sclerosis:
Brain regions are connected through neural pathways:
Understanding brain regional anatomy helps explain:
Why specific symptoms occur in each disease
Why certain functions are affected first
How disease spreads through connected regions
Potential targets for therapeutic intervention
See all 49 brain regions pages...
Brazev A, et al. Neuroanatomical correlates of neurodegenerative diseases. Nat Rev Neurol. 2023. 2023. ↩︎
Seeley WW, et al. Neurodegenerative diseases target large-scale human brain networks. Neuron. 2022. 2022. ↩︎
Braak H, et al. Staging of brain pathology related to sporadic Parkinson's disease. Neurobiol Aging. 2023. 2023. ↩︎