Biology Neurobiology/Neuroscience Stroke and Neurological Disorders
Stroke and Neurological Disorders
Neurological disorders encompass a wide range of conditions affecting the brain, spinal cord, and nerves, with stroke being a critical acute example. A stroke occurs when a disruption in blood flow—either from a blockage (ischemia) or bleeding (hemorrhage)—deprives brain tissue of oxygen, leading to rapid cell death and subsequent loss of function. This field also includes chronic and progressive diseases such as Alzheimer's, Parkinson's, and multiple sclerosis, which involve the gradual deterioration of neural structures or functions. Ultimately, the study of these disorders focuses on the underlying neurobiological pathologies that impair the nervous system's ability to process information and control the body, resulting in diverse cognitive, motor, and sensory deficits.
1.1.
Neuroanatomy
1.1.1.
Central Nervous System
1.1.1.1.1. Gross Anatomy and Surface Landmarks
1.1.1.1.1.1. External Brain Surfaces
1.1.1.1.1.2. Anatomical Orientation and Planes
1.1.1.1.1.3. Major Sulci and Gyri
1.1.1.1.1.4. Brain Weight and Volume
1.1.1.1.2. Cerebral Hemispheres
1.1.1.1.2.1.1. Prefrontal Cortex
1.1.1.1.2.1.1.1. Dorsolateral Prefrontal Cortex
1.1.1.1.2.1.1.2. Ventromedial Prefrontal Cortex
1.1.1.1.2.1.1.3. Orbitofrontal Cortex
1.1.1.1.2.1.2. Motor Cortex
1.1.1.1.2.1.2.1. Primary Motor Cortex
1.1.1.1.2.1.2.2. Premotor Cortex
1.1.1.1.2.1.2.3. Supplementary Motor Area
1.1.1.1.2.1.3. Broca's Area
1.1.1.1.2.1.3.1. Location and Anatomy
1.1.1.1.2.1.3.2. Language Production Functions
1.1.1.1.2.1.4. Frontal Lobe Functions
1.1.1.1.2.1.4.1. Executive Functions
1.1.1.1.2.1.4.2. Working Memory
1.1.1.1.2.1.4.3. Personality and Behavior
1.1.1.1.2.1.4.4. Motor Planning
1.1.1.1.2.2. Parietal Lobe
1.1.1.1.2.2.1. Somatosensory Cortex
1.1.1.1.2.2.1.1. Primary Somatosensory Cortex
1.1.1.1.2.2.1.2. Secondary Somatosensory Areas
1.1.1.1.2.2.1.3. Somatotopic Organization
1.1.1.1.2.2.2. Spatial Processing
1.1.1.1.2.2.2.1. Spatial Attention
1.1.1.1.2.2.2.2. Visuospatial Integration
1.1.1.1.2.2.2.3. Body Schema
1.1.1.1.2.2.3. Language Processing Areas
1.1.1.1.2.2.3.1. Angular Gyrus
1.1.1.1.2.2.3.2. Supramarginal Gyrus
1.1.1.1.2.3. Temporal Lobe
1.1.1.1.2.3.1. Auditory Cortex
1.1.1.1.2.3.1.1. Primary Auditory Cortex
1.1.1.1.2.3.1.2. Auditory Association Areas
1.1.1.1.2.3.2. Wernicke's Area
1.1.1.1.2.3.2.1. Language Comprehension
1.1.1.1.2.3.2.2. Phonological Processing
1.1.1.1.2.3.3. Memory Structures
1.1.1.1.2.3.3.1. Hippocampus
1.1.1.1.2.3.3.2. Parahippocampal Gyrus
1.1.1.1.2.3.3.3. Entorhinal Cortex
1.1.1.1.2.3.4. Limbic Components
1.1.1.1.2.3.4.2. Temporal Pole
1.1.1.1.2.4. Occipital Lobe
1.1.1.1.2.4.1. Primary Visual Cortex
1.1.1.1.2.4.1.1. Retinotopic Organization
1.1.1.1.2.4.1.2. Ocular Dominance Columns
1.1.1.1.2.4.2. Visual Association Areas
1.1.1.1.2.4.2.1. Secondary Visual Areas
1.1.1.1.2.4.2.2. Visual Processing Streams
1.1.1.1.2.5. Insular Cortex
1.1.1.1.2.5.1. Gustatory Functions
1.1.1.1.2.5.2. Visceral Sensation
1.1.1.1.2.5.3. Interoception
1.1.1.1.2.5.4. Pain Processing
1.1.1.1.3.1.1. Thalamic Nuclei
1.1.1.1.3.1.1.1. Relay Nuclei
1.1.1.1.3.1.1.2. Association Nuclei
1.1.1.1.3.1.1.3. Intralaminar Nuclei
1.1.1.1.3.1.2. Sensory Relay Functions
1.1.1.1.3.1.3. Motor Integration
1.1.1.1.3.1.4. Consciousness and Arousal
1.1.1.1.3.2.1. Hypothalamic Nuclei
1.1.1.1.3.2.2. Autonomic Regulation
1.1.1.1.3.2.3. Endocrine Control
1.1.1.1.3.2.4. Homeostatic Functions
1.1.1.1.3.2.5. Circadian Rhythms
1.1.1.1.3.3.1. Pineal Gland
1.1.1.1.3.4.1. Subthalamic Nucleus
1.1.1.1.3.4.2. Motor Control Functions
1.1.1.1.4.1.1.1. Superior Colliculus
1.1.1.1.4.1.1.2. Inferior Colliculus
1.1.1.1.4.1.2.1. Red Nucleus
1.1.1.1.4.1.2.2. Periaqueductal Gray
1.1.1.1.4.1.3. Cranial Nerve Nuclei
1.1.1.1.4.1.3.1. Oculomotor Nucleus
1.1.1.1.4.1.3.2. Trochlear Nucleus
1.1.1.1.4.1.4. Substantia Nigra
1.1.1.1.4.1.4.1. Pars Compacta
1.1.1.1.4.1.4.2. Pars Reticulata
1.1.1.1.4.2.1. Pontine Nuclei
1.1.1.1.4.2.2. Cranial Nerve Nuclei
1.1.1.1.4.2.2.1. Trigeminal Nuclei
1.1.1.1.4.2.2.2. Abducens Nucleus
1.1.1.1.4.2.2.3. Facial Nucleus
1.1.1.1.4.2.2.4. Vestibulocochlear Nuclei
1.1.1.1.4.2.3. Respiratory Centers
1.1.1.1.4.2.3.1. Pneumotaxic Center
1.1.1.1.4.2.3.2. Apneustic Center
1.1.1.1.4.3. Medulla Oblongata
1.1.1.1.4.3.1. Cranial Nerve Nuclei
1.1.1.1.4.3.1.1. Glossopharyngeal Nucleus
1.1.1.1.4.3.1.2. Vagus Nucleus
1.1.1.1.4.3.1.3. Accessory Nucleus
1.1.1.1.4.3.1.4. Hypoglossal Nucleus
1.1.1.1.4.3.2. Vital Centers
1.1.1.1.4.3.2.1. Cardiovascular Center
1.1.1.1.4.3.2.2. Respiratory Center
1.1.1.1.4.3.2.3. Swallowing Center
1.1.1.1.4.3.3. Olivary Complex
1.1.1.1.5.1. Anatomical Divisions
1.1.1.1.5.1.2. Cerebellar Hemispheres
1.1.1.1.5.1.3. Flocculonodular Lobe
1.1.1.1.5.2. Functional Divisions
1.1.1.1.5.2.1. Vestibulocerebellum
1.1.1.1.5.2.2. Spinocerebellum
1.1.1.1.5.2.3. Cerebrocerebellum
1.1.1.1.5.3. Cerebellar Cortex
1.1.1.1.5.3.1. Purkinje Cells
1.1.1.1.5.3.2. Granule Cells
1.1.1.1.5.3.3. Molecular Layer
1.1.1.1.5.4. Deep Cerebellar Nuclei
1.1.1.1.5.5. Motor Coordination
1.1.1.1.5.6. Balance and Posture
1.1.1.1.5.7. Cognitive Functions
1.1.1.2.1.1. External Anatomy
1.1.1.2.1.2. Spinal Segments
1.1.1.2.1.3. Conus Medullaris
1.1.1.2.2. Regional Organization
1.1.1.2.2.1. Cervical Region
1.1.1.2.2.1.1. Cervical Enlargement
1.1.1.2.2.1.2. Upper Limb Innervation
1.1.1.2.2.2. Thoracic Region
1.1.1.2.2.2.1. Sympathetic Outflow
1.1.1.2.2.2.2. Intercostal Innervation
1.1.1.2.2.3. Lumbar Region
1.1.1.2.2.3.1. Lumbar Enlargement
1.1.1.2.2.3.2. Lower Limb Innervation
1.1.1.2.2.4. Sacral Region
1.1.1.2.2.4.1. Pelvic Innervation
1.1.1.2.2.4.2. Autonomic Functions
1.1.1.2.3. Cross-Sectional Anatomy
1.1.1.2.3.1. Gray Matter Organization
1.1.1.2.3.1.1. Dorsal Horn
1.1.1.2.3.1.2. Ventral Horn
1.1.1.2.3.1.3. Intermediate Zone
1.1.1.2.3.2. White Matter Tracts
1.1.1.2.4. Dermatomes and Myotomes
1.1.1.2.4.1. Sensory Distribution
1.1.1.2.4.2. Motor Distribution
1.1.1.2.4.3. Clinical Testing
1.1.1.2.5.1. Ascending Pathways
1.1.1.2.5.1.1. Dorsal Column-Medial Lemniscal Pathway
1.1.1.2.5.1.2. Spinothalamic Tract
1.1.1.2.5.1.3. Spinocerebellar Tracts
1.1.1.2.5.2. Descending Pathways
1.1.1.2.5.2.1. Corticospinal Tract
1.1.1.2.5.2.2. Rubrospinal Tract
1.1.1.2.5.2.3. Vestibulospinal Tract
1.1.1.2.5.2.4. Reticulospinal Tract
1.1.2.
Peripheral Nervous System
1.1.2.1.1. Olfactory Nerve
1.1.2.1.3. Oculomotor Nerve
1.1.2.1.4. Trochlear Nerve
1.1.2.1.5. Trigeminal Nerve
1.1.2.1.8. Vestibulocochlear Nerve
1.1.2.1.9. Glossopharyngeal Nerve
1.1.2.1.11. Accessory Nerve
1.1.2.1.12. Hypoglossal Nerve
1.1.2.1.13. Clinical Testing Methods
1.1.2.1.13.1. Sensory Testing
1.1.2.1.13.2. Motor Testing
1.1.2.1.13.3. Reflex Testing
1.1.2.2.1. Nerve Root Organization
1.1.2.2.2.1. Cervical Plexus
1.1.2.2.2.2. Brachial Plexus
1.1.2.2.2.3. Lumbar Plexus
1.1.2.2.2.4. Sacral Plexus
1.1.2.2.3. Peripheral Nerve Distribution
1.1.2.2.4. Nerve Conduction Principles
1.1.2.3. Autonomic Nervous System
1.1.2.3.1. Sympathetic Division
1.1.2.3.1.1. Sympathetic Chain
1.1.2.3.1.2. Preganglionic Neurons
1.1.2.3.1.3. Postganglionic Neurons
1.1.2.3.1.4. Physiological Effects
1.1.2.3.1.4.1. Cardiovascular Effects
1.1.2.3.1.4.2. Respiratory Effects
1.1.2.3.1.4.3. Metabolic Effects
1.1.2.3.2. Parasympathetic Division
1.1.2.3.2.1. Cranial Parasympathetic Outflow
1.1.2.3.2.2. Sacral Parasympathetic Outflow
1.1.2.3.2.3. Ganglia and Innervation
1.1.2.3.2.4. Physiological Effects
1.1.2.3.2.4.1. Digestive Effects
1.1.2.3.2.4.2. Cardiovascular Effects
1.1.2.3.2.4.3. Glandular Secretion
1.1.2.3.3. Enteric Nervous System
1.1.2.3.3.1. Myenteric Plexus
1.1.2.3.3.2. Submucosal Plexus
1.1.2.3.3.3. Gastrointestinal Control
1.1.3.
Cerebrovascular System
1.1.3.1.1. Anterior Circulation
1.1.3.1.1.1. Internal Carotid Artery
1.1.3.1.1.1.1. Cervical Segment
1.1.3.1.1.1.2. Petrous Segment
1.1.3.1.1.1.3. Cavernous Segment
1.1.3.1.1.1.4. Supraclinoid Segment
1.1.3.1.1.2. Anterior Cerebral Artery
1.1.3.1.1.2.1. Territory and Branches
1.1.3.1.1.2.2. Anterior Communicating Artery
1.1.3.1.1.3. Middle Cerebral Artery
1.1.3.1.1.3.2. Superior Division
1.1.3.1.1.3.3. Inferior Division
1.1.3.1.1.3.4. Lenticulostriate Arteries
1.1.3.1.2. Posterior Circulation
1.1.3.1.2.1. Vertebral Arteries
1.1.3.1.2.1.1. Origin and Course
1.1.3.1.2.1.2. Posterior Inferior Cerebellar Artery
1.1.3.1.2.2. Basilar Artery
1.1.3.1.2.2.1. Formation and Course
1.1.3.1.2.2.2. Pontine Branches
1.1.3.1.2.2.3. Superior Cerebellar Artery
1.1.3.1.2.3. Posterior Cerebral Artery
1.1.3.1.2.3.1. Territory and Branches
1.1.3.1.2.3.2. Posterior Communicating Artery
1.1.3.1.3. Circle of Willis
1.1.3.1.3.1. Anatomical Components
1.1.3.1.3.2. Anatomical Variations
1.1.3.1.3.3. Collateral Circulation
1.1.3.1.3.4. Clinical Significance
1.1.3.1.4. Cerebral Autoregulation
1.1.3.1.4.2. Pressure Limits
1.1.3.1.4.3. Pathological States
1.1.3.2.1. Superficial Venous System
1.1.3.2.1.1. Cortical Veins
1.1.3.2.1.2. Superficial Middle Cerebral Vein
1.1.3.2.2. Deep Venous System
1.1.3.2.2.1. Internal Cerebral Veins
1.1.3.2.2.3. Great Cerebral Vein
1.1.3.2.3. Dural Venous Sinuses
1.1.3.2.3.1. Superior Sagittal Sinus
1.1.3.2.3.2. Inferior Sagittal Sinus
1.1.3.2.3.3. Straight Sinus
1.1.3.2.3.4. Transverse Sinuses
1.1.3.2.3.5. Sigmoid Sinuses
1.1.3.2.4. Jugular Venous System
1.1.3.2.4.1. Internal Jugular Veins
1.1.3.2.4.2. External Jugular Veins
1.1.3.3. Blood-Brain Barrier
1.1.3.3.1. Structure and Function
1.1.3.3.2. Tight Junctions
1.1.3.3.3. Transport Mechanisms
1.1.3.3.4. Clinical Implications
1.1.3.4. Cerebrospinal Fluid System
1.1.3.4.1.1. Choroid Plexus
1.1.3.4.1.2. CSF Composition
1.1.3.4.2. CSF Circulation
1.1.3.4.2.1. Ventricular System
1.1.3.4.2.2. Subarachnoid Space
1.1.3.4.3.1. Arachnoid Granulations
1.1.3.4.3.2. Lymphatic Drainage
1.2.
Neurophysiology
1.2.1.
Cellular Neurophysiology
1.2.1.1.1. Neuronal Structure
1.2.1.1.1.4. Synaptic Terminals
1.2.1.1.2. Membrane Properties
1.2.1.1.2.1. Lipid Bilayer
1.2.1.1.2.3. Membrane Proteins
1.2.1.1.3.1. Myelin Structure
1.2.1.1.3.2. Nodes of Ranvier
1.2.1.1.3.3. Saltatory Conduction
1.2.1.2. Membrane Potential
1.2.1.2.1. Resting Membrane Potential
1.2.1.2.1.1. Ion Gradients
1.2.1.2.1.2. Sodium-Potassium Pump
1.2.1.2.1.3. Equilibrium Potentials
1.2.1.2.2. Action Potentials
1.2.1.2.2.1. Threshold and Initiation
1.2.1.2.2.2. Depolarization Phase
1.2.1.2.2.3. Repolarization Phase
1.2.1.2.2.4. Hyperpolarization Phase
1.2.1.2.3. Propagation Mechanisms
1.2.1.2.3.1. Continuous Conduction
1.2.1.2.3.2. Saltatory Conduction
1.2.1.2.3.3. Conduction Velocity Factors
1.2.1.2.4. Refractory Periods
1.2.1.2.4.1. Absolute Refractory Period
1.2.1.2.4.2. Relative Refractory Period
1.2.1.3. Synaptic Transmission
1.2.1.3.1. Chemical Synapses
1.2.1.3.1.1. Presynaptic Events
1.2.1.3.1.2. Neurotransmitter Release
1.2.1.3.1.3. Postsynaptic Events
1.2.1.3.1.4. Synaptic Integration
1.2.1.3.2. Electrical Synapses
1.2.1.3.2.1. Gap Junctions
1.2.1.3.2.2. Electrical Coupling
1.2.1.3.3. Synaptic Plasticity
1.2.1.3.3.1. Short-Term Plasticity
1.2.1.3.3.2. Long-Term Potentiation
1.2.1.3.3.3. Long-Term Depression
1.2.2.
Neurotransmitter Systems
1.2.2.1. Excitatory Neurotransmitters
1.2.2.1.1.1. Synthesis and Metabolism
1.2.2.1.1.2. Receptor Types
1.2.2.1.1.3. Physiological Functions
1.2.2.1.1.4. Pathological Roles
1.2.2.1.2.1. Synthesis and Metabolism
1.2.2.1.2.2. Nicotinic Receptors
1.2.2.1.2.3. Muscarinic Receptors
1.2.2.1.2.4. Central and Peripheral Functions
1.2.2.2. Inhibitory Neurotransmitters
1.2.2.2.1.1. Synthesis and Metabolism
1.2.2.2.1.2. GABA-A Receptors
1.2.2.2.1.3. GABA-B Receptors
1.2.2.2.1.4. Inhibitory Functions
1.2.2.2.2.1. Synthesis and Function
1.2.2.2.2.2. Glycine Receptors
1.2.2.2.2.3. Spinal Cord Functions
1.2.2.3. Modulatory Neurotransmitters
1.2.2.3.1.1. Synthesis and Metabolism
1.2.2.3.1.2. Dopamine Pathways
1.2.2.3.1.3. Receptor Subtypes
1.2.2.3.1.4. Motor and Cognitive Functions
1.2.2.3.2.1. Synthesis and Metabolism
1.2.2.3.2.2. Serotonin Pathways
1.2.2.3.2.3. Receptor Subtypes
1.2.2.3.2.4. Mood and Sleep Functions
1.2.2.3.3.1. Synthesis and Metabolism
1.2.2.3.3.2. Noradrenergic Pathways
1.2.2.3.3.3. Receptor Subtypes
1.2.2.3.3.4. Arousal and Attention
1.2.2.3.4.1. Synthesis and Function
1.2.2.3.4.2. Histamine Receptors
1.2.2.3.4.3. Sleep-Wake Regulation
1.2.3.
Glial Cell Biology
1.2.3.1.1. Morphology and Distribution
1.2.3.1.2. Metabolic Support Functions
1.2.3.1.2.1. Glucose Metabolism
1.2.3.1.2.2. Lactate Shuttle
1.2.3.1.2.3. Potassium Buffering
1.2.3.1.3. Blood-Brain Barrier Maintenance
1.2.3.1.4. Neurotransmitter Uptake
1.2.3.1.5. Reactive Astrogliosis
1.2.3.2.1. Development and Maturation
1.2.3.2.2. Myelin Formation
1.2.3.2.4. Remyelination Capacity
1.2.3.3.1. Peripheral Myelination
1.2.3.3.2. Wallerian Degeneration
1.2.3.3.3. Nerve Regeneration Support
1.2.3.4.1. Origin and Development
1.2.3.4.2. Immune Surveillance
1.2.3.4.3. Phagocytic Functions
1.2.3.4.4. Neuroinflammation
1.2.3.4.5. Synaptic Pruning
1.2.3.5.1. Ventricular Lining
1.2.3.5.3. Ciliary Functions
1.2.4.
Neural Networks and Integration
1.2.4.1. Sensory Processing
1.2.4.1.1. Sensory Transduction
1.2.4.1.3. Sensory Integration
1.2.4.2.1. Motor Unit Organization
1.2.4.2.2. Motor Control Hierarchies
1.2.4.3. Cognitive Functions
1.2.4.3.1. Attention Networks
1.2.4.3.3. Executive Control
1.2.4.4. Consciousness and Arousal
1.2.4.4.1. Reticular Activating System
1.2.4.4.2. Thalamic Functions
1.2.4.4.3. Cortical Integration