Brain Disorders & Behavior - Quiz 1

Detailed vocabulary flashcards based on lecture notes covering neuroanatomy, directional terminology, cellular structures, the CSF system, blood supply, stroke mechanisms, traumatic brain injuries, and neurological infections.

Gyrus

A 'ridge' of cerebral cortex

Sulcus

A 'valley' of cerebral cortex

Cortical sheet

The outer surface covering of cerebral cortex, composed of gray matter (neuron cell bodies)

Cerebral cortex

The large, folded part of the brain that sits above the cerebellum and brainstem, made up of gray and white matter

Cerebellum

Latin for 'little brain' - the small, highly ridged portion of brain that sits inferior to the cerebral cortex and posterior to the brainstem

Gray matter

Outer 'bark' of cerebral cortex composed of neuronal cell bodies; where computations happen; consists of $6$ layers in most of cortex

White matter

Inner region of cerebral cortex composed of axons; can be thought of as the 'wiring' connecting different regions of gray matter

Anterior

Towards the front of the brain

Posterior

Towards the back of the brain

Superior

Towards the top of the brain

Inferior

Towards the bottom of the brain

Lateral

The lateral view shows the surface of a cerebral hemisphere under the ears

Medial

The medial view shows the inner surface of a cerebral hemisphere

Dorsal

Towards the top of the brain (towards the back surface of the body in brainstem & spinal cord)

Ventral

Towards the bottom of the brain (towards belly surface in brainstem & spinal cord)

Rostral

Towards the front of the brain (towards top surface in brainstem/spinal cord; means 'beak')

Caudal

Towards the back of the brain (towards bottom surface in brainstem/spinal cord; means 'tail')

Sagittal view

A vertical slice of the brain cut from anterior to posterior, giving a view from left or right

Coronal view

A vertical slice of the brain cut from superior to inferior, giving a view from front or back

Axial view

A horizontal slice of the brain cut from left to right, giving a view from top or bottom

Frontal lobe

The anterior portion of cerebral cortex; involved in emotion, cognition, and executive control

Parietal lobe

The superior posterior portion of cerebral cortex; superior to occipital and temporal lobes, posterior to frontal lobe

Temporal lobe

The inferior portion of cerebral cortex; anterior to occipital lobe and inferior to the others

Occipital lobe

The posterior portion of cerebral cortex; primarily involved in vision processing

Central sulcus

The sulcus dividing the frontal and parietal lobes, surrounded by motor and sensory cortex

Lateral fissure

The gap that divides the temporal from the frontal and parietal lobes

Parieto-occipital sulcus

The sulcus that divides the parietal and occipital lobes

Brodmann's Areas

$\sim 50$ cytoarchitectural areas defined by cell size, density, layer number/thickness, and myelinated axon density

Central Nervous System (CNS)

Composed of the brain and spinal cord

Peripheral Nervous System (PNS)

Composed of peripheral nerves that connect the CNS to limbs, trunk, and organs

Autonomic Nervous System (ANS)

A subdivision of the PNS that controls visceral (internal organ) functions

Cranial nerves

A set of $12$ specialized nerves ($\text{CNs } I-XII$) that act as the PNS to the head and neck

Meninges

Three protective layers of tissue between the brain and skull

Dura mater

The durable, leathery outer protective layer of the meninges ('hard mother')

Arachnoid mater

The spider web-like middle protective layer of the meninges filled with CSF ('spider-like mother')

Pia mater

The thin, shiny, inner protective layer that 'shrink-wraps' the brain ('tender mother')

Neuron

The basic cell in the brain that processes and transmits information via electrical and chemical signals

Dendrite

The branched portion of a neuron which receives inputs from synapses and sends small depolarizations to the cell body

Cell body

The 'main' portion of a cell containing the nucleus, mitochondria, and organelles necessary for survival

Axon hillock

The base of the axon where it meets the cell body; where action potentials are initiated

Axon

The long cell structure that carries action potentials away from the cell body to the synapse

Node of Ranvier

Small gaps between myelin sheaths involved in fast action potential propagation

Synapse

The region/space where information flows from one neuron to another; includes the synaptic cleft

Axon terminal

The very end of a neuron's axon branch, specialized to release neurotransmitters in response to action potentials

Glial cell

Cells that surround neurons in CNS and PNS; provide myelination and support; most abundant cell type in CNS

Myelin sheath

A layer of protective tissue wrapped around axons to hasten transmission of action potentials

Corpus callosum

The main white matter connection integral for communication between the two cerebral hemispheres

Cerebral Spinal Fluid (CSF)

The fluid surrounding brain and spinal cord that cushions the nervous system; similar to blood plasma

Ventricle

CSF-filled cavities in the brain; four total (left, right, third, and fourth)

Choroid plexus

Specialized cells lining the ventricles responsible for creating CSF

Lumbar puncture

A method to withdraw CSF for testing from the spinal column just below the spinal cord

Arachnoid granulations

Bubble-like portions of the arachnoid mater that remove CSF from around the brain; CSF is 'recycled' into bloodstream

Hydrocephalus

'Water on the brain' - disorder of CSF flow or reuptake; leads to head enlargement, developmental problems, eye gaze changes, and if untreated, death

Non-communicating hydrocephalus

Hydrocephalus caused by obstruction of normal CSF flow (e.g., by tumor, clot, or malformation)

Communicating hydrocephalus

Hydrocephalus caused by problem with CSF uptake through arachnoid granulations; whole CSF system has increased pressure

Shunt

A tube placed inside the skull to drain off extra fluid (e.g., ventriculoperitoneal shunt for hydrocephalus)

Blood brain barrier

A filtering mechanism of capillaries that blocks passage of certain substances (infectious agents, immune cells, some drugs)

Circle of Willis

A circle of arteries that supply blood to the brain; allows for collateral blood flow

Carotid artery

Blood vessel that supplies head and neck; divides into internal (supplies Circle of Willis) and external; supplies anterior part of brain

Vertebral artery

Blood vessel running up the back of the neck; two merge at skull base to form basilar artery; supplies posterior brain

Basilar artery

Artery supplying pons, cerebellum, posterior cerebrum, and inner ear; formed by merging vertebral arteries

Middle cerebral artery

Artery supplying lateral cerebral cortex and anterior temporal lobes; strokes affect face, arm, and language

Anterior cerebral artery

Arteries supplying most medial portions of frontal lobes and superior medial parietal lobes; strokes affect leg use

Stroke

Rapid loss of brain tissue and function from disruption of blood supply to the brain

Transient Ischemic Attack (TIA)

'Mini stroke' - same symptoms as stroke, but only temporary

Ischemia

Lack of oxygen arising from restriction in blood supply

Ischemic stroke

Stroke resulting from restriction of blood flow into brain tissue

Hemorrhagic stroke

Stroke resulting from blood bleeding into the brain, damaging tissue

Thrombus

A clot or atherosclerotic plaque that forms in place, obstructing blood flow

Embolus

A moving clot that lodges in a small vessel

Carotid stenosis

Abnormal narrowing of carotid artery, often from atherosclerotic plaque formation

Hemorrhage

Bleeding; the loss of blood from the circulatory system

Aneurysm

A localized, blood-filled bulge of a blood vessel

Subarachnoid hemorrhage

Bleeding between arachnoid and pial meningeal layers (in CSF space)

Intracerebral hemorrhage

Bleeding within brain tissue itself (below pia mater)

Intraventricular hemorrhage

Bleeding from vessels along ventricles; bleeding directed into ventricles

tPA

Drug from tissue plasminogen activator; breaks down blood clots; used to treat ischemic stroke if within $3$ hours of onset

Arteriovenous malformation (AVM)

Tangle of abnormal blood vessels connecting arteries and veins; increased bleeding risk and decreased oxygen flow (no capillary bed)

Venous malformation

Congenital vascular anomalies involving veins or veins and arteries; increased bleeding/abnormal oxygen delivery risk

Venous thrombosis

Blood clot in a vein; in brain may occur in venous sinuses and block blood flow out, often fatal

Hematoma

Solid swelling of clotted blood within tissues; causes local mass effects in brain

Subdural hematoma

Bleeding below dura (between dura and brain) from trauma like fall tearing bridging veins; slower onset (venous blood)

Epidural hematoma

Bleeding between skull and dura from trauma/skull fracture; faster, more serious onset (arterial blood)

Bridging veins

Veins draining neural tissue that puncture through dura to venous sinuses; may tear with trauma causing subdural hematoma

Traumatic Brain Injury (TBI)

Damage to brain from external physical force; commonly called concussion

Coup/contra-coup injury

Results from focal injury or whiplash; both the directly hit side and opposite side are damaged

Diffuse shearing injury

Rapid acceleration/deceleration forces separate cell bodies and axons, causing widespread brain injury

Phineas Gage

Man who survived train spike through frontal cortex but was emotionally disturbed afterward

Meningitis

Viral or bacterial infection of the meninges; symptoms: rash, stiff neck, headache, vomiting, mental status change

Encephalitis

Usually viral (herpes) infection of brain tissue; symptoms: personality changes, seizures, weakness

Rabies

Virus entering brain via peripheral nerves causing diffuse swelling; symptoms: headaches, fever, rages, inability to swallow water, coma, death

Prion

Infectious protein molecules

Creutzfeld-Jakob Disease (CJD)

Mad cow disease; prion infection kills brain cells creating 'lakes' in tissue; symptoms: dementia, coordination problems

Cysticercosis

Condition from pork tapeworm infection; symptoms: headache, stroke-like effects, brain swelling, risk of death

Encephalopathy

General term for disorder/disease of the brain; syndrome of global brain dysfunction from many possible causes

Brain Tumor

Any intracranial growth from abnormal, uncontrolled cell division; causes damage directly or via mass effect

Holoprosencephaly

Congenital disorder from failure of embryonic forebrain to divide into double lobes; severe skull and facial defects

Autism

Diffuse developmental disorder impairing social interaction and communication

Epilepsy

Chronic neurological disorder characterized by recurring seizures

Neurodegeneration

Progressive loss of structure or function of neurons, including neuronal death