PSY 0505

major devisions of the nervous system

Peripheral Nervous System

Central Nervous System

Central Nervous System (CNS)

brain and spinal cord

the brain and spinal cord are supplemented by/also include:
1. meninges
2. cerebral spinal fluid
3. ventricles

What are meninges

membranes that surround the brain and spinal cord; provide a tight anchoring of the CNS to the surrounding bones able to prevent side-to-side movement and providing stability

What are ventricles

fluid filled spaces in the brain

what is cerebral spinal fluid

Forms a liquid cushion that gives buoyancy the the CNS organs. Prevents the brain from crushing under its own weight. Protects the CNS and blows other traumas. Nourishes the brain and carries chemical signals throughout it.

Parts of the brain

medulla oblongata
pons
cerebellum
midbrain
thalamus
hypothalamus
limbic system

medulla oblongata

Part of the brainstem that controls vital life-sustaining functions such as heartbeat, breathing, blood pressure, and digestion.

pons

the part of the brainstem that links the medulla oblongata and the thalamus.

sleep and arousal

cerrebellum

A large structure of the hindbrain that controls fine motor skills.

midbrain

Region between the hindbrain and the forebrain; it is important for hearing and sight.

thalamus

the brain's sensory switchboard, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla

-information relay station. All information from your body's senses (except smell) must be processed through your thalamus before being sent to your brain's cerebral cortex for interpretation. Your thalamus also plays a role in sleep, wakefulness, consciousness, learning and memory.

Hypothalamus

A neural structure lying below the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward, our fight or flight response, activate sympathetic nervous system

releasing hormones.
maintaining daily physiological cycles.
controlling appetite.
managing sexual behavior.
regulating emotional responses.
regulating body temperature.

limbic system

associated with emotions and drives

amygdala, hippocampus, cingulate cortex, fornix, septum, hypothalamus, and mammillary body

Peripheral Nervous System (PNS)

the sensory and motor neurons that connect the central nervous system to the rest of the body

include/composed of:

Cranial and Spinal Nerves
Autonomic and Somatic Nervous Systems Sympathetic and Parasympathetic Nervous Systems

cranial nerves

12 pairs of nerves that carry messages to and from the brain

spinal nerves

31 pairs of nerves arising from the spinal cord

Automatic Nervous System (ANS)

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart). Its sympathetic division arouses; its parasympathetic division calms.

*contains sympathetic and parasympathetic divisions

Sympathetic Nervous System (SNS)

the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations

Parasympathetic Nervous System (PNS)

the division of the autonomic nervous system that calms the body, conserving its energy

what does the peripheral nervous system's somatic and autonomic nervous systems both contain?

Afferent Nerves and Efferent Nerves

afferent nerves (sensory nerves)

Nerves that carry information about the external environment to the brain and spinal cord via sensory receptors

*blue

efferent nerves (motor nerves)

nerves that carry information out of the brain and spinal cord to other areas of the body

*red

What are the part of the autonomic nervous system' efferent nerves?

the sympathetic and parasympathetic nervous system

Three parts of the brain?

Forebrain, Midbrain, Hindbrain

Five parts of the spinal cord?

Cervical, Thoracic, Lumbar, Sacral, Coccygeal

Meninge order?

Scalp to skull to dura mater, to arachnoid mater, to subarachnoid space, then pia mater, then brain

The Four Ventricles

Lateral ventricle, Third Ventricle, Cerebral Aqueduct, Fourth Ventricle

Dura Mater

thick, outermost layer of the meninges surrounding and protecting the brain and spinal cord

Arachnoid Mater

middle layer of the meninges; cushions the brain

Pia Mater

the delicate innermost membrane enveloping the brain and spinal cord, like plastic wrap, very pliable, gets into all indentations of surface of brain

supply your brain tissue with blood

Five Major divisions of the human brain

Telencephalon, Diencephalon, Mesencephalon (midbrain), Metencephalon, and Myelencephalon

Telencephalon

limbic system
Cerebral Cortex
*forebrain

Diencephalon contains

Thalamus and hypothalamus
*forebrain

Mesencephalon (midbrain) contains

tectum and tegmentum, cerebral aqueduct
*midbrain

Metencephalon (hindbrain)

pons, cerebellum, fourth ventricle

Myelencephalon contains (medulla oblongata)

medulla oblongata
*hindbrain

Telecephalon function

- receives input from entire cerebral cortex
- very important in starting, stopping + monitoring movement, especially slow repetitive movements like arm swinging when walking
- also regulate intensity of movement so we can do several activities at once
-Communication and Language Function

Diencephalon function

memory processing and emotional response

primary relay and processing center for sensory information and autonomic control

Mesencephalon (midbrain) function

functions in motor movement, particularly movements of the eye, and in auditory and visual processing.

Metencephalon function

handles unconscious processes and jobs, such as your sleep-wake cycle and breathing

sensory innervation to face
initiates and coordinates movement and regulates temperature

consists of the cerebral cortex, subcortical white matter (commissural, association, and projection fibers), and basal nuclei.

Myelencephalon function

responsible for basic life support functions like respiration and heart rate

Identify the neuroanatomical directions (10)

Anterior
Posterior
Superior
Inferior
Medial
Lateral
Dorsal
Ventral
Rostral
Caudal

Anterior

In front of; toward the face

Posterior

Behind, toward the back

Superior

Above; toward the head

Inferior

Below; toward the feet

Medial

Toward the midline

Lateral

Toward the edge

Dorsal

Toward the top of the brain or the back of the spinal cord

Ventral

Toward the bottom of the brain or the front of the spinal cord

Rostral

Toward the front of the brain or the top of the spinal cord

Caudal

Toward the back of the brain or the bottom of the spinal cord

Cervical spine

The portion of the spinal column consisting of the first seven vertebrae that lie in the neck.

Thoraric Spine

the middle section of your spine

Lumbar spine

The sacral spine consists of 5 fused sacral vertebrae. It is easily distinguishable as an upside-down triangular shape. The two lateral surfaces (sides) are smooth for articulation (loose connection) with the iliac bones of the pelvis.

Coccygeal Spine

the region of the coccyx (tailbone), 4 vertebrae

Cerebral Cortex Lobes (4)

frontal lobe, parietal lobe, occipital lobe, temporal lobe

Association Cortexes (5)

Amygdala.
Hippocampus.
Thalamus.
Sensory Cortex.
Visual Cortex

Lateral Ventricle

a complex C-shaped lateral portion of the ventricular system within each hemisphere of the brain

Third Ventricle

The midline ventricle that conducts cerebrospinal fluid from the lateral ventricles to the fourth ventricle.

Cerebral Aqueduct

connects the third and fourth ventricles

Fourth Ventricle

the passageway within the pons that receives cerebrospinal fluid from the third ventricle and releases it to surround the brain and spinal cord

Frontal Lobe

A region of the cerebral cortex that has specialized areas for movement, abstract thinking, planning, memory, and judgement

Frontal Lobe

A region of the cerebral cortex that has specialized areas for movement, abstract thinking, planning, memory, and judgement

Parietal Lobe

A region of the cerebral cortex whose functions include processing information about touch.

Primary somatosensory cortex

Association cortex

Occipital Lobe

A region of the cerebral cortex that processes visual information

Primary visual cortex
Association cortex

Temporal Lobe

A region of the cerebral cortex responsible for hearing and language.

Primary auditory cortex
Association cortex

Amygdala

A limbic system structure involved in memory and emotion, particularly fear and aggression.

Hippocampus

A neural center located in the limbic system that helps process explicit memories for storage.

Thalamus

relays messages between lower brain centers and cerebral cortex

Sensory Cortex

area at the front of the parietal lobes that registers and processes body touch and movement sensations

Visual Cortex

The visual processing areas of cortex in the occipital and temporal lobes.

Brain Lobes (4)

frontal, parietal, occipital, temporal

Rostral

toward the nose

Neuraxis

an imaginary line drawn through the center of the length of the central nervous system, from the bottom of the spinal cord to the front of the forebrain

Types of neural planes and sections

the sagittal plane, the coronal plane, and the transverse plane

Sagittal Plane

vertical division of the body into right and left portions

Cornonal Plane

divides body into front and back

Transverse Plane

horizontal division of the body into upper and lower portions

Cervical Nerves (8 pairs)

8 pairs; They siminulate muscle movements in your neck, shoulder, arm and hand, and provide sensation

Thoracic nerves (12 pairs)

12 pairs; network of nerves in your shoulders that carries movement and sensory signals from your spinal cord to your arms and hands.

Lumbar Nerves (5 pairs)

5 pairs; nerves run down from your lower back and merge with other nerves to form a network of nerves that control pain signals and the movements of your lower limbs

Sacral Nerves (5 pairs)

5 pairs; provides motor and sensory nerves for the posterior thigh, most of the lower leg, the entire foot, and part of the pelvis

Coccygeal nerve (1 pair)

1 pair; sensory and motor innervation to their respective dermatomes and myotomes. They also provide partial innervation to several pelvic organs, including the uterus, fallopian tubes, bladder, and prostate.

Ventricle Order

lateral, 3rd, cerebral aqueduct, 4th ventricle

Order of the brain specific (front to back)

telencephalon (cerebral hemispheres), diencephalon, mesencephalon (midbrain), metencephalon, myelencephalon (medulla), spinal cord

Order of the brain general (front to back)

forebrain (telencephalon, diencephalon), midbrain (mesencephalon), hindbrain (metencephalon, myelencephalon ), spinal cord

Primary Motor Cortex

the section of the frontal lobe responsible for voluntary movement- feet, trunk, hands, finger, face, lip

integration of motor commands with the ongoing somatic sensory state of the body,

Primary Sensory Cortex

regions of the parietal lobe that initially process information from the senses- feet, trunk, hands, finger, face, lip

Association Cortex

higher order (executive) function
planning
thinking and worrying
language production
working memory

Orbitofrontal Cortex (OFC)

has association cortex

• impulsivity control
• personality
• understanding of social norms (-our decisions on how we will react in social situations)
• processing reward information

Parietal (lobe) Cortex

Primary somatosensory cortex:
• process somatic sensations
• detect touch
• proprioception (body position)
• nociception (pain)
• temperature
Association cortex:
• body awareness
• kinesthesis
• mathematical calculations
• aspects of reading & writing
- such as combining sound,
appearance, and function of words

Temporal (lobe) Cortex

Primary auditory cortex:
• first relay station for auditory
information
• awareness of sound
Association cortex:
• auditory processing
• language processing
• interprets speech

Occipital (lobe) Cortex

Primary visual cortex:
• detection of static object
• detection of moving object
• pattern recognition
Association cortex:
• complex processing
• visual interpretation
• spatial relation between objects

Tectum

- superior colliculi (visual relay)
- inferior colliculi (auditory relay)

Tegmentum

- rostral end of reticular
formation (arousal system)
- periaqueductal gray area
(mediates analgesia)
- substantia nigra
(sensorimotor system)
- ventral tegmental area
(reward system)
- red nucleus (sensorimotor system)

Mammillary Body

one of a pair of limbic system structures that are connected to the hippocampus

recollective memory. Memory information begins within the hippocampus

Septum

a thin membrane located at the midline of the brain between the two cerebral hemispheres, or halves of the brain. It is connected to the corpus callosum \-- a collection of nerve fibers that connect the cerebral hemispheres.

Fornix

a fiber tract that extends from the hippocampus to the mammillary body

a white matter bundle located in the mesial aspect of the cerebral hemispheres

Cingulate Cortex

primary cortical component of the limbic system, involved in emotional and cognitive processing