CBNS Lecture 1 Midterm Review

Neuroscience

The study of all aspects of nervous system function from molecular to cellular to systems to cognititive (behavioral)

7 Components of Nervous System

1. Genes

2. Molecules

3. Cells

4. Synaptic Connections

5. Neural Circuits

6. Behavioral Circuit Systems

7. Cognitive Input

The 2 Main Divisions of the Mammalian Nervous System

Central NS and Peripheral NS

Central NS Divisions

Brain and Spinal Cord

Gray Matter

Found on the outside of the brain, rich in neuronal cell bodies

White Matter

Found under gray matter, long range myelinated axonal fiber tracts

Cerebrum

Right hemisphere receive sensation and controls left side, Left side receives sensation and controls right

Cerebellum

Movement control center, left controls left, right controls right

Brain Stem

Relays info from cerebrum to spinal cord and cerebellum and vice versa, controls vital functions (breathing, consciousness, control of body temp)

Neocortical Evolution

1. Cortex amount has evolved, not structure

2. Brain has primary + secondary sensory areas, motor areas

3. Association areas of cortex evolved more recently, have higher order processing

Features of Cerebral Cortex in Vertebrates

1. Cell Bodies in Layers/Sheets

2. Surface Layer Separated from Pia Mater (Layer 1)

3. Apical Dendrites Form Multiple Branches

Meninges (Definition and 3 Types)

Layers that surround the brain

1. Dura Mater

2. Arachnoid Membrane

3. Pia Mater

Arachnoid Membrane

Found below Dura Mater, filled with cerebrospinal fluid

Ventricular System Components

Consists of Ventricles, Choroid Plexus, and Subarachnoid Space

Ventricles

Caverns and canals filled with cerebrospinal fluid

Choroid Plexus

Consists of capillaries and separated from ventricles by choroid epithelial cells

Choroid Epithelial Cells

Cells that filter fluid to become CSF

Spinal Cord

Info conduit from brain to rest of body

Dorsal Root

Sensory fibers (Cell body outside the CNS)

Ventral Root

Outgoing motor fibers (cell body inside CNS, project axons to PNS)

Peripheral NS Divisions

Somatic and Autonomic

Somatic PNS

Innervates skin, joints, muscles, contains dorsal root ganglia and ventral roots

Dorsal Root Ganglia

Clusters of neuronal cell bodies outside spinal cord, contains somatic sensory axons

Autonomic PNS

Innervates internal organs, blood vessels, glands

Afferent Nerves

These nerves carry info to the brain/spinal cord

Efferent Nerves

These nerves carry info away from the brain/spinal cord

CT Scan

Generates an image of a slice of the brain using X-Ray beams, revealed organization of gray and white matter, position of ventricles

Magnetic Resonance Imaging (MRI)

Based on how hydrogen atoms respond in the brain to changes in a strong magnetic field , more detailed than CT scan, no X-Rays required, images can be captured in any angle

Functional MRI (fMRI)

Detects changes in regional blood flow and metabolism in brain (due to active neurons demanding more glucose and oxygen)

Diffusion Tensor Imaging

MRI-based imaging technique used to estimate location and orientation of white matter tracts

Alzheimer's Disease

Progressive degenerative disease of brain, characterized by dementia and always fatal

Autism

Disorder emerging in early childhood characterized by impairments in communication and social interactions, and restrictive and repetitive behaviors

Cerebral Palsy

Motor disorder caused by damage to the cerebrum before/during/soon after birth

Depression

Serious disorder of mood characterized by insomnia, loss of appetite, feelings of dejection

Epilepsy

Condition characterized by periodic disturbances of brain electrical activity that can lead to seizures, loss of conciousness, and sensory disturbances

Multiple Sclerosis

Progressive disease that affects nerve conduction, characterized by episodes of weakness, lack of coordination, and speech disturbance

Parkinson's Disease

Progressive disease of the brainn that leads to difficulty in intiating voluntary movement

Schizophrenia

Severe psychotic illness characterized by delusions, hallucinations, and bizarre behavior

Spinal Paralysis

Loss of feeling and movement caused by traumatic damage to the spinal cord

Stroke

Loss of brain function caused by disruption of the blood supply, leading to permanent sensory, motor, or cognitive deficit