Central Nervous System Lecture

This set of flashcards focuses on key terms and concepts related to the anatomy and functions of the Central Nervous System, including structures, functions, diseases, and protective mechanisms.

Central Nervous System (CNS)

Composed of the brain and spinal cord.

Function of CNS

Integration/interpretation of incoming sensory information and sending out a motor response to effector organs.

Four regions of the brain

Cerebral hemispheres, Diencephalon, Brain Stem, Cerebellum.

Gray Matter

Contains dendrites, cell bodies, and axon terminals; all synapses are found here.

White Matter

Contains myelinated axons, passes messages between different areas of gray matter.

Cerebral Cortex

Outer layer of gray matter in the brain.

Gray Matter location in the brain

Peripheral.

White Matter location in the brain

Central.

Central Canal

Found at the center of gray matter in the spinal cord.

Ventricles

Hollow chambers in the brain filled with cerebrospinal fluid (CSF).

Third Ventricle location

Found in the diencephalon.

Cerebellum function

Controls coordination of movement.

Motor Areas of the Cerebral Cortex

Regions controlling voluntary movement.

Primary Motor Cortex function

Allows for conscious control of skilled/precise voluntary movements.

Pyramidal Cells

Large neurons found in the primary motor cortex.

Motor Homunculus

Spatial representation of body in the primary motor cortex.

Premotor Cortex function

Helps plan movements by selecting and sequencing basic motor movements.

Broca's Area

Specialized motor speech area directing muscles involved in speech production.

Sensory Areas of the Cerebral Cortex

Regions responsible for conscious awareness of sensations.

Primary Somatosensory Cortex function

Receives information from general sensory receptors in skin.

Somatosensory Association Cortex function

Integrates sensory input relayed from primary somatosensory cortex.

Primary Visual Cortex function

Receives visual information from the retina.

Primary Auditory Cortex function

Interprets sound from the inner ear.

Vestibular Cortex function

Allows for conscious awareness of balance/orientation.

Olfactory Cortex function

Allows for conscious awareness of different odors.

Gustatory Cortex function

Perception of taste stimuli.

Lateralization of Cortical Functioning

Division of labor between the two hemispheres.

Cerebral Dominance

One hemisphere dominates a particular task, often related to language.

Cerebral White Matter

Located deep to the cortical gray matter; facilitates communication in the CNS.

Association Fibers

Connect different areas of the same hemisphere.

Commissural Fibers

Connect corresponding areas of different hemispheres.

Basal Nuclei

Filters out inappropriate responses related to muscle movement, emotions, and cognition.

Thalamus function

Relays sensory information to the cerebral cortex.

Hypothalamus function

Main visceral control center controlling autonomic processes.

Epithalamus function

Secretes melatonin; helps regulate the sleep-wake cycle.

Midbrain function

Regulates motor movement, hearing, vision, and alertness.

Pons function

Controls respiration and bladder function.

Medulla Oblongata function

Regulates heart rate, blood pressure, and respiratory rhythm.

Cerebellum function

Coordinates smooth movements and maintains posture.

Limbic System

The 'emotional brain' responsible for emotions and memory.

Amygdaloid body function

Response to perceived threats with fear or aggression.

Cingulate gyrus function

Expresses emotions and resolves mental conflicts.

Reticular Activating System (RAS)

Keeps the cerebral cortex alert and filters out irrelevant stimuli.

Broca’s area responsibility

Production and comprehension of language.

Wernicke’s area

Responsible for language comprehension.

Short-term memory (STM)

Stores small amounts of information for short periods.

Long-term memory (LTM)

Stores large amounts of information for longer periods.

Declarative memory

Involves learning explicit information.

Nondeclarative memory

Memories acquired through repetition; difficult to unlearn.

Protection of the Brain

Involves the skull, meninges, cerebrospinal fluid, and blood-brain barrier.

Dura Mater

Most external layer of the meninges.

Subarachnoid Space

Contains cerebrospinal fluid and spiderweb-like projections.

Cerebrospinal Fluid (CSF)

Liquid surrounding the brain and spinal cord.

Blood-Brain Barrier (BBB)

Protective barrier preventing harmful substances from entering CNS.

Paresthesia

Abnormal sensation due to dorsal root damage.

Flaccid Paralysis

Loss of voluntary muscle control due to ventral root damage.

Spastic Paralysis

Involuntary muscle movement due to damage to upper motor neurons.

Transection of the spinal cord

Complete severing leading to total sensory/motor loss below the injury.

Paraplegia

Loss of lower limb function due to transection between T1 and L1.

Quadriplegia

Loss of all limb function due to transection in the cervical region.

Cerebral Cortex Functions

Self-awareness, sensation, communication, memory, voluntary movement initiation.

Contralateral Hemispheric Function

Right hemisphere controls left side of body and vice versa.

Cognitive Functions of the Cerebellum

Involvement in thinking, language, and emotion control.

Functional Brain Systems

Networks of neurons spanning multiple brain regions for related tasks.

Hypothalamus monitoring

Controls temperature, water balance, and food intake by monitoring blood.

Cingulate Gyrus interactions

Causes emotional responses to smells.

Cerebellar Cortex decision-making

Decides best way to execute movement based on sensory information.

Cerebral association areas

Integrate diverse information for perception and cognition.

Motor output functions from cerebellum

Smooth coordination of voluntary muscle movements.

Types of Memory Transfer

Emotional state, rehearsal, association, and automatic memory can influence memory formation.

CSF Functions

Protection, buoyancy, and nutrient transport for the CNS.

Homeostatic Imbalances of the Brain

Includes conditions like concussions and neurological diseases.

Alzheimer’s Disease symptoms

Memory loss, disorientation, and changes in personality.

Parkinson’s Disease symptoms

Tremors, stiff facial expressions, and altered posture.

Cross-sectional Anatomy of Spinal Cord

Central canal, gray matter deep, white matter superficial.

Dorsal Horns function

Receive somatic and visceral sensory input.

Ventral Horns function

Contains motor output neurons.

Lateral Horn location

Found only in thoracic and superior lumbar segments.

Nerve Roots

Where sensory and motor axons enter or exit the spinal cord.

Dorsal Root Ganglia

Swelling where cell bodies of sensory neurons are found.

Significance of Meninges

Protects CNS and contains cerebrospinal fluid.

Cerebrospinal fluid production location

Produced by choroid plexus in ventricles.

Melatonin

Hormone secreted by the pineal gland to regulate sleep-wake cycle.

Impulses from the brain stem

Involved in facial sensation and movement.