Neuro Week 1: Gross Structures of Nervous System (CNS, PNS, Lobes)

This area of the nervous system includes the processing parts

Central Nervous System (CNS)

The environment provides info to this area of the nervous system and it can repair

What are the 2 subgroups?

Peripheral Nervous System (PNS)

• Including cranial and spinal nerves

Positional term for anterior/cephalic

*Think towards nose

Rostral

Positional term for posterior, towards tail

Caudal

Positional term for inferior, basal

Ventral

Positional term for superior/towards ceiling

*Think like a shark fin

Dorsal

Positional term for opposite side

Contralateral

Ex. Stroke on one side of the brain affects the other side of the body

Positional term for same side

Ipsilateral

The axis positional terms are based on

Neuroaxis

This plane cuts vertically, front and back

Think like a crown on your head

Coronal

This plane cuts the brain into top and bottom

Horizontal

This plane cuts the brain into left and right sides

*Includes most popular cut

Sagittal

*Mid-sagittal cut

These are the cells of the brain

Specialized for what?

Do they get replaced?

Neurons

Specialized for information transmission/processing (electrical and chemical)

No they do not get replaced

What is it called when the brain moves back and fourth in your head in a car crash for example?

Cue contra cue

These cells provide structural and nutritional support

They are like mother neurons, involved in housekeeping (clean damaged neuron)

Create this major structure?

Support cells (glia)

Create myelin sheath

This type of communication is within neurons, sending info

Electrical

This type of communication is between neurons, includes neurotransmitters

Chemical

The neuron is a decision-making unit specifically at what structure?

Axonal hillock

This component of the neuron receives information, sometimes from thousands of other neurons

*Think like branches

Dendrites

This structure of the neuron includes the nucleus, DNA, and is critical for the health of the rest of the neuron

Damage does not come back

Collection makes up ____ matter

Cell body (soma)

Grey matter

Typical information transmission from _____ to _____ neuron?

Dendrites —> Cell Body —> Axon ——> Axon terminals/terminal buttons

This structure of the neuron sends information/action potentials (2msec at each axon segment) along with integration/decision

Each neuron has one

A collection makes up ______ matter

Axon

Makes up white matter (myelin sheath)

This structure of the neuron sends information and is involved with the release of neurotransmitters

Axonal terminals/terminal buttons

These types of neurons are afferent, input (bring in info), and sensory

Relating to all the senses (sight, taste, hearing, smell, touch)

Receptors

These types of neurons are responsible for internal processing, linkng sensation and ‘output”/’thinking’

Only in the brain and spinal cord (so not in animals like frogs)

Interneurons

These types of neurons are involved in output, efferent

Including muscles and organs, movement (brain —> muscle)

Motor neurons

The small space separating the neuron sending information from the receiving neuron

Synaptic cleft

This is the term for the neuron sending information

*Relative to a synapse

Presynaptic

This is the term for the neuron receiving information

*Relative to a synapse

Postsynaptic

A collection of axons is known as what?

Nerve

2 components of the Peripheral Nervous System:

PNS carries this information including skeletal movement and sensation (sensory - pain, touch, temp)

PNS has this control over glands and organs (ex. panic attack, hyperventilate, high HR, sweat, digestive system stops)

Carries somatic information

Autonomic control

Afferent associated with what?

Efferent associated with what?

Sensory

Motor

A collection of axons makes up what in the CNS (also known as a fasciculus or column)

Makes up what in PNS?

Tract

Nerve

A collection of neuron cell bodies makes up what in the CNS

In PNS?

Nucleus

Ganglion (not many)

What is the CNS’s 2 major functions?

*Hint: one has to do with information and the other has to do with involuntary movements

1. Conduit for information flow from brain —> the rest of the body (and vice versa)

   Bring information (descending, efferent/motor) from the brain to muscles, glands and organs

   Bring information from sensory structures (ascending, afferent, sensory) on the skin, organs, and within muscles to the brain

2. Organizes reflexive movement independently of input from the brain via reflex arcs

These spinal cord sections are myelinated bundles of neuron fibers (axons) transmitting efferent and afferent information

Tracts (white matter)

This spinal cord section is cell bodies processing with efferent information in the ventral horn and afferent information in the dorsal horn

Gray matter

Efferent vs Afferent

1. To muscles, organs, or glands

2. From sensory structures

3. Sensory information

4. Motor information

1. Efferent

2. Afferent

3. Afferent

4. Efferent

In the CNS there are 3 general regions of the brain what are they (oldest/caudal to recently evolved/rostral)?

1. Hindbrain

2. Midbrain

3. Forebrain

The hindbrain includes what 3 structures?

1. Medulla

2. Pons

3. Cerebellum

In the hindbrain, this area includes the nuclei for ‘vegetative funcitions’ (basic functions such as breathing and HR control), incluiding the vagus nerve

Medulla

In the hindbrain, this area includes movement structures, among others

Pons

In the hindbrain, this area involves coordination, balance, control of both fast and ballistic movements

Cerebellum

What are the 2 major sections of the midbrain?

3 subsections?

Tectum (dorsal)

Cerebral Peduncle

• Tegmentum

• Substantia nigra

• Crus cerebri

In the midbrain, this structure includes the superior colliculus and inferior colliculus with visual and auditory reflexes

Like a roof

Tectum (dorsal)

This structure of the midbrain involves movement structures, among others

Anterior to tectum

Tegmentum

This is a “black substance” in the midbrain, damaged in Parkinsonism

Substantia Nigra

This connects the forebrain to the spinal cord

Includes what 3 structures?

Brainstem

Medulla, pons, midbrain

This area of the forebrain has 2 hemispheres connected via the corpus callosum (and other commissures)

With lateeralization of function

Cerebrum

This side of the cerebrum controls language and analytic/detail

Left

This side of the cerebrum controls synthetic/holistic functions (build up, big picture)

Right

The forebrain is further divided into what 2 sections (superficial and interior)?

Cortical (superficial, exterior, ‘cortex”)

Subcortical (interior, deep)

What are the 4 main subcortical structures of the forebrain?

1. Diencephalon

2. Basal ganglia

3. Limbic system

4. Corpus callosum

The diencephalon includes what 4 structures?

1. Hypothalamus (hormone release, ANS - organs + glands, motivated behaviors - sex, sleep, hunger drive)

2. Thalamus (relay nuclei)

3. Subthalamus

4. Epithalamus

This subcortical structure of the forebrain is usually in the PNS but is involved in movement control and memory (not factual, how to do things - like ride a bike)

Basal ganglia

This subcortical structure of the forebrain includes the hippocampal formation and amygdala involved in emotion and FACTUAL memory

Limbic system

This is the oldest cortex immediately surrounding the corpus callosum

It is part of the limbic system (emotion) and hippocampus (memory, navigation)

Cingulate gyrus/cortex

The newest surface of the cortex, prefrontal area

Neocortex

Hypothalamus and thalamus make up what structure of the forebrain?

Diencephlon

Cortical convolution known as “valleys”, very deep=”fissures”

“Hills?”

Sulcus

Gyrus

What are the 4 major sulci?

Median Longitudinal Fissure (aka sagittal fissure)

Lateral sulcus/fissure

Central sulcus

Parieto-occipital sulcus/fissure (seen in sagittal cut of brain)

*Pictures on slides

What divides the cortex into four lobes?

Sulci/fissures

This gyrus and sulcus make up the primary motor cortex (contralateral muscle control)

Located rostral to the central sulcus

Pre-central gyrus and pre-central sulcus

These 3 gyri surround the longitudinal fissure

Superior frontal gyrus (posterior parts=motor)

Middle frontal gyrus (association cortex)

Inferior frontal gyrus

Located left posterior in the frontal lobe, controlling expressive speech (ability to speak)

Broca’s area

The prefrontal region of the frontal lobe (most anterior/rostral part) is something only humans have, it controls what 3 things?

1. Executive functions

2. Future planning

3. Advanced cognitive functions (consequences of behavior, can lead to anxiety)

Medial to lateral in the frontal lobe on the inside of the sagittal cut is what (3)?

Gyrus rectus

Olfactory sulcus (with olfactory bulb)

Orbital gyrus (emotion, personality)

In the parietal lobe, this is the primary somatosensory cortex?

Post central gyrus

In the parietal lobe this is the somatosensory association cortex (spatial localization)?

Superior parietal lobule

These 2 structures are a part of the inferior parietal lobule?

Involved with visual/auditory language integration

1. Supramarginal gyrus

2. Angular gyrus

In the parietal lobe (ventral/medial), posterior/caudal to the central sulcus is this lobule with the marginal sulcus and following it is this gyrus?

These are sites of what integration?

Paracentral Lobule followed by precuneus (gyrus)

Sit of multiple sensory integration

Forming the posterior border of the parietal lobe (seen only in midsagittal views)

Parietooccipital sulcus

This sulcus forms the inferior/ventral border of the parietal lobe

Subparietal sulcus

Somatosensory strip is more anterior or posterior to motor strip?

Anterior

In the temporal lobe (lateral aspect) there are these 3 gyri?

Superior temporal gyrus

Middle temporal gyrus

Inferior temporal gyrus

This gyrus is the primary auditory cortex of the temporal lobe

Superior temporal gyrus

The left posterior area of the temporal lobe is known as what and controls receptive speech?

Wernicke’s area

These gyri of the temporal lobe are known for visual object/form recognition and include inferotemporal visual areas

Middle and inferior temporal gyri

In the temporal lobe (looking ventral) moving medially from the inferior temporal gyrus are these 5 structures (lateral to medial)?

Functions (3)?

1. Occipitotemporal sulcus

2. Occipitotemporal gyrus

3. Collateral sulcus

4. Parahippocampal gyrus (most medial)

5. Uncus (anterior, medial to PHG, like a thumb)

Function in memory, learning, and emotion

In the medial aspect (sagittal cut) of the occipital lobe you have what 4 structures (rostral to caudal)?

1. Cuneus

2. Calcarine sulcus/fissure

3. Lingual gyrus

4. Posterior part of occipitotemporal gyrus