Major Divisions of the Brain

Question 1

Neuraxis

Answer 1

The spine-to-brain path.

move from the nose to the tail of the animal (brain down to the spinal cord); decide what is anterior (rostral) and posterior (caudal)

Question 2

Anterior

Answer 2

Towards the front of the brain.

Question 3

Posterior

Answer 3

Towards the back of the brain.

Question 4

Superior

Answer 4

Higher/above in the brain.

Question 5

Inferior

Answer 5

Lower/below in the brain.

Question 6

Rostral

Answer 6

Towards the front of the brain in humans and animals. Points up the spinal curvature in humans.

Question 7

Dorsal

Answer 7

Towards the back. To humans, points to the top of our brain, but points sideways on our back. If a human had a fins like a fish, those would be visual indicators of the dorsal directions.

Question 8

Caudal

Answer 8

Towards the “tail” (so for animals, towards the back of the brain, but for humans is both referring to towards the back of the brain and downwards on the axis of the brainstem/spinal cord).

Question 9

Ventral

Answer 9

Towards the belly. In humans, points to the bottom of the brain and to the belly on the spinal axis.

Question 10

Coronal Plane

Answer 10

Vertical plane that divides anterior and posterior sections of the brain.

Question 11

Horizontal Plane

Answer 11

Divides the brain into superior (upper) and inferior (lower) sections.

Question 12

Sagittal Plane

Answer 12

Vertical plane that divides the brain into left and right sections. Is called a midsagittal plane if it divides the brain directly in half.

Question 13

Spinal Cord

Answer 13

Vertebrae → cervical→ thoracic → lumbar→ sacral→ coccygeal

Question 14

Narrows/tapers when from cervical to coccygeal

Answer 14

The sacral region has fewer sensory neurons, and their information must travel upward to the brain. The cervical region is thicker due to more sensory input, and as motor outputs decrease down the spinal cord, the cord becomes thinner.

Question 15

Spinal cord damage

Answer 15

loss of function related to segment of damage

Question 16

Major divisions of the brain

Answer 16

Forebrain:
telencephalon
diencephalon

Midbrain:
mesencephalon

Hindbrain:
metencephalon
myelencephalon (or medulla)

Question 17

What is the dorsal/ventral organization in the spinal cord?

Answer 17

The dorsal side carries sensory (afferent) information, while motor (efferent) information exits from the ventral side.

Question 18

Myelencephalon

Answer 18

Intersection between the brain and the spinal cord- largely comprised of tracts; bundles of axons

Involuntary control of life-sustaining functions
Part of our brain that keeps our heart beating, diaphragm move even if we’re unconscious: swallowing reflex

Question 19

Myelencephalon

How does spinal cord damage affect function?

Answer 19

Damage to the cervical region is the most severe because it blocks all afferent inputs and motor outputs, while damage to the thoracic region only affects inputs from lower segments like the lumbar and sacral regions, leaving cervical inputs intact.

Question 20

Myelencephalon

Function of Reticular formation or the reticular activating system

Answer 20

consists of many nuclei that regulate basic functions. As you move higher in the system, it becomes essential for wakefulness, sleep, arousal, and attention.

Damage to this region can cause severe disruptions to life, such as difficulty staying awake, and may even be fatal.

Question 21

Metencephalon

Answer 21

Contains many afferent and efferent pathways and also houses part of the reticular formation.

differentiates pons and cerebellum

Question 22

Myelecephalon

Doctors are reluctant to perform surgery on the medulla

Answer 22

Small amount of damage; fatal or catastrophic results

Question 23

Metencephalon

Role of the cerebellum, and what effects does damage to it have?

Answer 23

cerebellum makes up about 10% of brain volume and is primarily responsible for motor coordination rather than motor control.

not life-threatening but impairs the ability to make smooth, unconscious adjustments in movements, such as grabbing a cup, forcing individuals with damage to make these corrections consciously.

Question 24

Metencephalon

What is the ventral side of the pons

Answer 24

A pale structure containing many myelinated axons (both afferent and efferent), continuing from the spinal cord and medulla.

Question 25

# Metencephalon What happens if the ventral side of the pons is damaged?

Answer 25

Damage to the pons, such as a stroke, can result in a combination of numbness, lack of coordination, and disruptions to the sleep-wake cycle.

Question 26

Mesencephalon (midbrain)

Answer 26

Divide midbrain by dorsal (roof or tectum) Comprised of a roof (tectum) and a floor (tegmentum) AKA the Boston Pizza Part of the Brain

Question 27

# Mesencephalon Superior colliculi

Answer 27

vision with respect to eye movement

Question 28

# Mesencephalon Inferior colliculi

Answer 28

auditory with respect to head/body orientation

Question 29

# Mesencephalon Tectum

Answer 29

Comprised of the inferior colliculus and the superior colliculus, which deal with auditory and visual processing

Question 30

# Mesencephalon Damage to the mesencephalon

Answer 30

Stokes- trouble from automatic eye movement (orienting our eyes upward); Parinaud’s syndrome

Question 31

# Mesencephalon Tegmentum

Answer 31

* Contains part of reticular formation * More fibres * Periacqueductal grey (main input is from the amygdala, motor control; ex: freezing when scared, flinching) * Dopamine-producing regions

Question 32

# Metencephalon Pons

Answer 32

large white-matter bulge, continuing from spinal cord/medulla * essential in sending information to your body ## Footnote Damage to this region: combination of numbness/ lack of feeling in the body, lack of coordination, sleeping and waking state

Question 33

# Mesencephalon Red nucleus

Answer 33

primarily involved in motor coordination, closely connected to the cerebellum, helping to coordinate fine motor actions (swinging of arms when walking) ## Footnote if damaged: motor coordination problems

Question 34

# Mesencephalonss (Tegmentum) Dopamine-producing regions

Answer 34

Substantia nigra and Ventral tegmental area (VTA)

Question 35

# Mesencephalon Pattern of function

Answer 35

motor control, sensory processing, vision and hearing reflexes, and regulating consciousness and sleep-wake cycles.

Question 36

Diencephalon

Answer 36

Comprised of two structures: The thalamus and hypothalamus

Question 37

# Diencephalon Thalamus

Answer 37

an egg-shaped structure in the middle of your brain. It's known as a relay station of all incoming motor (movement) and sensory information — hearing, taste, sight and touch (but not smell) | inputs from sensory systems, cerebellum, basal ganglia

Question 38

# Diencephalon Sensory info in the Thalamus

Answer 38

goes from thalamus to cortex but equal numbers come from cortex to thalamus= continuous loop

Question 39

# Diencephalon Damage to the thalamus

Answer 39

people who have damage to thalamus disorder in conscious: look awake but they don’t really seem there

Question 40

# Diencephalon Functions of the hypothalamus

Answer 40

sex, aggression, feeding, sleep, wake, more

Question 41

# Diencephalon Corticothalamic loops

Answer 41

communication pathways between the cerebral cortex and the thalamus that play a critical role in processing and regulating sensory, motor, and cognitive information. ## Footnote Two-Way Communication: These loops involve reciprocal connections, where the cortex sends signals to the thalamus (corticothalamic projections), and the thalamus sends information back to the cortex (thalamocortical projections).

Question 42

# Diencephalon Hypothalamus

Answer 42

Key intersection with endocrine system via the pituitary gland (master gland)

Question 43

# Diencephalon Damage to the hypothalamus

Answer 43

Regulatory role, interfere with sleeping, eating, sex Damage in this region is hard to pin down

Question 44

# Diencephalon Narcolepsy and the hypothalamus

Answer 44

Inability to stay awake; transition from awake to sleep so fast due to lost of specific neurons in the hypothalamus

Question 45

Telencephalon

Answer 45

Largest in the human brain by volume (not by total number of neurons)

Question 46

# Telencephalon What are parts included in the telencephalon

Answer 46

Cortex, amygdala, hippocampus

Question 47

# Telencephalon Damage

Answer 47

wide-ranging in its symptoms | seizure, stroke, alzheimer's, cog. impairment

Question 48

# Telencephalon Cerebral cortex | The cortex, neocortex

Answer 48

The largest and most prominent feature of the human brain

Question 49

# Telencephalon Why is the cortex highly convoluted

Answer 49

No special reason, just part of the brain that has the best ability to learn is in the cortex; we need more cortex so we fold it up and convolute it | Other mammals have smooth brains: The lissencephalic (smooth) cortices

Question 50

# Hemisphere Corpus callosum

Answer 50

The corpus callosum is located in the central hemisphere and connected by cerebral commissures. It connects the left and right hemisphere and allows for communication between them. ## Footnote largest white matter structure in the brain

Question 51

What is interesting about the damage in the convolutions

Answer 51

Some disorders affect the sulcus first before the gyrus

Question 52

# Hemisphere Longitudinal fissure

Answer 52

Separates the ledt and right hemispheres

Question 53

# Hemisphere Callosotomy

Answer 53

where some axons connecting the left and right hemispheres of the brain are cut to reduce excessive spontaneous activity. Patients report feeling no immediate effects after the procedure. However, they may experience manual disagreement, where one hand acts independently of the other (e.g., one hand buttoning a shirt while the other unbuttons). ## Footnote rare treatment for epilepsy

Question 54

# Hemisphere Contralateral organization

Answer 54

Left hemisphere governs the right half of the word Right hemisphere governs the left half of the world Right hand is controlled by left and vice versa

Question 55

# Hemisphere Left hemisphere dominance for language

Answer 55

Speaking, listening, language comprehension right hemisphere has limited capacity or not so effective

Question 56

# Hemisphere 4 lobes in the cerebral cortex

Answer 56

frontal, parietal, occipital, temporal lobe

Question 57

# Hemisphere Central fissure

Answer 57

separates frontal and parietal lobes

Question 58

# Hemisphere Lateral fissure

Answer 58

separates temporal lobe from frontal/parietal ## Footnote Deep in the letral fissure: the insula- older cortex underneath the cerebral cortex

Question 59

# Hemisphere Limbic system

Answer 59

Amygdala (latin word for almond), HTh, mammillary body, hippocampus, fornix, cingulate cortex (related to sensation of pain, decision-making, tough decisions), septum, olfactory bulb | symptoms from damage can vary from region to region

Question 60

# Hemisphere Basal Ganglia

Answer 60

Includes striatum (caudate + putamen) and globus pallidus (pale globe), sometimes others (e.g. subthalamic nucleus) Critical in movement, skills, habits, decision making Muscle memory Learning skilled but not too thoughtful actions–playing piano, riding a bike Somehow a part of drug addiction

Question 61

Nucleus accumbens

Answer 61

subregion of striatum/caudate, sometimes called ventral striatum (opposite of dorsal) Connected to drugs and addiction: important for motivation

Question 62

Anatomy of the cortical layers

Answer 62

Layer 6- deepest 3,5,6 much thicker in motor cortex 4 is thick for

Question 63

Sensory cortex vs motor cortex

Answer 63

In the sensory cortex, layers are thicker and packed with input-processing neurons (INPUT) In the motor cortex, layers for sending signals are more prominent, reflecting their role in controlling movements. (OUTPUT)

Question 64

Differences between parts of the cortex

Answer 64

can be used to make maps e.g. Brodmann areas

Question 65

Line between motor and somatosensory (most anterior for parietal)

Answer 65

Central fissure

Question 66

Precentral gyrus

Answer 66

Located in the frontal lobe, this is the motor cortex (Brodmann area 4), responsible for controlling voluntary movements.

Question 67

Do we use only 10% of our brains?

Answer 67

NO. Ex. drinking a glass of water Make a decision that you want to drink water- prefrontal cortex How to pick up a glass of water- Premotor areas; has the templates on how I should do it Executed into motor commands- Motor cortex; Send axons to spinal cord (efferent signal) regulates movement- basal ganglia Brain stem- pons Sensory info- weight of the glass etc- cerebellum Looping to other areas to find motor coordination

Question 68

Postcentral gyrus

Answer 68

Located in the parietal lobe, this is the somatosensory cortex (Brodmann areas 1-3), responsible for processing sensory information from the body.

Question 69

Meninges

Answer 69

Three layers of membranes that protect the brain and spinal cord. ## Footnote Pia mater, arachnoid mater, dura mater

Question 70

# 4 total, including the skull Layers that protect the brain and spinal cord

Answer 70

Skull -> Dura Mater -> Arachnoid mater -> Pia mater

Question 71

Cerebrospinal fluid (CSF)

Answer 71

Fluid that flows in and around the hollow/empty spaces of the brain and spinal cord. The brain produces CSF for nutrients, to remove waste, etc. but also is like an “airbag” in case we bump our heads. ## Footnote Flows down to central canal spinal cord- take a sample from spinal cord and withdraw the fluid and see what drug metabolize and see what's happening at the CNS

Question 72

Hydrocephalus

Answer 72

neurological disorder caused by an abnormal buildup of cerebrospinal fluid in the ventricles (cavities) deep within the brain Passageways get blocked but ventricles keep producing CSF= puts pressure into the brain Wants to drain but it can't so it pushes against neurons Ventricles will get larger and larger= hydrocephalus ## Footnote If let untreated, consequences on cognition

Question 73

Treatment for hydrocephalus

Answer 73

Insert an artificial tube (shunt) to drain from brain to abdomen

Question 74

Cerebral blood flow

Answer 74

Flow from blood to brain is **limited (supply)** because there is only 4 veins (2 in front and 2 at back) **No redundancy**, if 1 artery is blocked, that artery is gone; that's why stroke is so detrimental **No reserves**- energy brain consumes have no storage; drug overdose and no energy store= you can get brain damage ## Footnote neurons= no oxygenated blood for 4 minutes= they start dying

Question 75

# Mesencephalon periaqueductal gray

Answer 75

propagation and modulation of pain, sympathetic responses as well as the learning and action of defensive and aversive behaviors.

Question 76

Medial

Answer 76

Towards the middle (of the brain).

Question 77

Lateral

Answer 77

Towards the edge (of the brain).