Brain and Behavior
Chapter 1 Introduction
What is the brain? The brain is an organ, It consists of nervous tissue
The cells within this tissue are called nerve cells (neurons and glial cells)
What is behavior? Definition used in the book: Behavior consists of patterns in time
Examples: Movement, speech, attitude, blushing, thinking
→More practical definition: Any form of observable action or reaction of a person or animal in response to
external or internal stimuli→Most behaviors consist of a mix of inherited and learned actions.
Examples: Sucking reflex in newborns = inherited, Eating later in life = strongly influenced by learning/culture
This mixture varies considerably from species to species:
- Smaller, simpler nervous system→narrower range of behaviors that depend mainly on heredity, less
neuroplasticity→less learning processing possible
- Larger, more complex nervous systems→more complex behavioral patterns that depend on learning
The mind-body problem
Dualistic versus monistic philosophical views, Spiritualistic versus materialistic views (TL;DR: Nobody knows)
Brain and behavior
The brain is an organ, a physical object, living tissue. Behavior is action, not physical, but observable
This course is about the relationship between brain and behavior based on evidence from:
1. Evolution of brain and behavior in diverse animal species
2. Brain-behavior relationship in typical people
3. How brain changes in people with brain damage/dysfunction
A brief history of humankind
We do not descend from chimpanzees! → Men and chimpanzees do share a common Hominin ancestor
Hominins→ common ancestor originated ~ 5 million years ago, primates who walked upright, all hominins
evolved from this ancestor, humans only surviving hominin species
Some well-known ancestors (no details needed)
→at a certain point ancestor’s brain started to wave to have a bigger volume/size
-Australopithecus “southern ape” →originated ~ 4 million years ago in Africa (particularly south and east), brain
size ~400 cm 3 (0.4 kg), e.g.: australopithecus afarensis (Afar, Ethiopia): “Lucy”
-Homo habilis “handy man” →~2.5 – 1.5 million years ago, Africa, larger brain volume than australopithecus:
~800 cm 3 (0.8 kg), used simple stone tools, ate animal food
-Homo erectus “upright man” → ~1.5 million years ago, larger brain (900-1200 cm 3 – 0.89-1.18 kg), better
tools than homo habilis, migrated to Europe (Neanderthal) and Asia
-Homo sapiens “knowing man” →~120,000 years ago, originated in Africa, ~100.000 years ago, migrated to
Europe (Cro-Magnon, SW France), perhaps responsible for extinction of Neanderthal, cave art, the oldest are
aged ~30,000 years, brain volume about 1500 cm 3 (1.48 kg)
Evolution of human brain size
Encephalization quotient (EQ) = actual brain size / expected brain size (relative to body weight)
cat = average domestic animal EQ1, Australopithecus EQ2.5, Homo sapiens EQ 7.0 (way more than ancestor)
Our brain weight ~tripled in 4 million years time!
What is so special about the human brain? Modern humans have the largest brain size relative to body weight
How did our brain get so big? Theories:
- Lifestyle adjustments→social group size (~150) hunter-gatherer, eating fruit (more difficult to get than e.g. grass
but has more nutrients→to distinguish a green and a yellow banana you need color vision), use of fire (cooking),
more time for social interaction
- Efficient brain cooling→circulating blood functions as a radiator (like in a car engine, without cool system stops
working all together), enabled homo sapiens to maintain high metabolism (= more horsepower)→2% weight,
25% oxygen, 70% glucose
- Neoteny→(maturita’ sessuale) retention of juvenile features in the adult animal, adult humans closely resemble
the infants of gorillas and chimpanzees (e.g. large head relative to body size) +tend to explore more/curiosity
1
,Is a larger brain also a better brain (within species)? Answer: no
-Einstein's brain weighed only 1.2 kg, which is less than the average adult male brain (~1.4 kg)
-Men have ~10% more brain volume than women, but are not more intelligent
-Perhaps it is the (number of) connections between brain cells that matters?
NB: Most behavior is not innate but acquired during life and culturally determined!
Chapter 2 Brain anatomy and physiology
What is the nervous system’s functional anatomy?
This chapter describes the basic structure and function of the brain
Although the brain has structure, the brain is not a static organ; we are not born with a brain that remains
unchanged for the rest of our lives.
The brain is a plastic organ; neural tissue has the ability to adapt to the world→neural plasticity
Example: learning (without neural plasticity we wouldn’t be able to learn)
Navigating the brain – different orientation systems vedi bene immagine
- Brain-Body Orientation→illustrates brain structure location from the frame of reference of the human face
From Latin: “aimed towards or located” (arrows pointing different directions)
- Dorsal: dorsum→back (structures atop the brain or a structure within the brain are dorsal) ↑
- Ventral: venter→belly (structures toward the bottom of the brain or one of its parts are ventral)↓
- Medial: mediālis→middle (structures towards the brain’s midline are medial)→
- Lateral: laterālis side (structures located toward the sides are lateral)→
- Anterior: anterior before / in front of
- Posterior: posterior after / behind
- Spatial Orientation→illustrates brain structure location in relation to other body parts and body orientation
- Rostral: rostrum→beak (becco) =anterior
- Caudal: caudum→tail =posterior
- Superior: superior→above =dorsal
- Inferior: inferior→below =ventral
Animal brains are oriented similarly, but spinal-cord orientations may differ because many animals stand on ‘all
fours’. Compared with head orientation of a four-legged animal, dorsal and ventral take a 90* turn
counter-clockwise when describing the human or the bird brain→terminology shifted depending on the location
→Both ventral and dorsal seem to take a 90* turn because in the spinal cord ventral structures are still located
towards the belly side, but in the brain those structures are located toward the bottom side/below
- Anatomic Orientation→illustrates the direction of cut/section through human brain from the perspective of a viewer
Coronal section→cut in a vertical plane, from crown of the head down→frontal view of brain internal structures |
Horizontal section→cut falls along the horizon, looking down on the brain from above→dorsal view —
Sagittal section→cut lengthways from front to back, viewed from the side→medial view (sagitta=arrow, if you
want to kill someone you throw the arrow between their eyes→where the plane is, separate 2 hemispheres)
Brain protection – meninges & cerebrospinal fluid (CSF)
Meninges→triple layered membrane system that protects the brain from chemical and mechanical influences
from the outside, under the skull, before the brain tissue
1. Dura mater→outer layer, toughest one bc it’s double layered membrane (dura=tough mother), highly vascular
2. Arachnoid (+ Pia mater a.k.a leptomeninges, from λεπτός (Greek) leptos = thinner layers of the meninges)
if you take arachnoid apart it would look like a spider web (arachno), not highly vascular, consists of collagen and
other structures (elastic) but there are holes to allow veins from the dura mater to go through
3. Pia mater→highly vascular and sensitive, very soft (pia=soft), no receptors there (brain doesn’t have pain
receptors) headache→feeling not in the brain (it produces pain) but in the vascular system around it.
Subarachnoid space→space between arachnoid holes (below the arachnoid space)→filled with fluid CSF,
Cerebrospinal fluid, bc it runs between the brain (cerebrum) and the spinal cord (protects brain from concussion
when you move quickly, allows the brain to float around→brain tissue is very soft) average 125 ml (not much)
Triple layered system also around the spinal cord→in a small canal inside the bone structures (vertebra)
2
,Blood supply of the brain
- Vital to cool the brain efficiently→vaste network
- Brain=high metabolism organ (needs a lot of nutrients) and creates a lot of waste product→taken out by the
blood stream→venes system (waste out), arteries (oxygen in)
Cerebrovascular accident (CVA, ‘stroke’)
Brain can become life threatening bc it’s very vascular and the skull cannot expand (fixed structure) →every
additional fluid or tissue results in brain damage (compression/loss of oxygen supply)
-Ischemic CVA (80%) Blockage of blood vessel by clot (part of the brain is deprived of oxygen)→a clot blocks
blood flow to an area of the brain→treatment: make the blood thinner, make the clot out of the way
-Hemorrhagic CVA (20%)→Burst of vessel bleeding into the brain→bleeding occurs inside or around brain tissue
treatment: surgery to stop the bleeding (more serious, less common) if it happens on one side it affects also the
other→can lead to displacement of the midline of brain (brain squashed against the skull in the opposite side)
NB: behavioral consequences of stroke are extensively covered in subsequent course ‘Brain Dysfunction’
The brain from the outside Main structures visible from the outside:
1. Cerebrum (brain in latin)
2. Cerebellum (‘little cerebrum’)→little brain underneath the big brain
3. Brainstem→all the structures are built up the brainstem, involved in all kinds of cardiac functions (breathing,
blood pressure) without brainstem the brain doesn’t work at all bc needs to get the oxygen, but still it’s the
primitive portion of the brain →NB: the higher a structure is located physically, the ‘higher’ its function. (higher in
the sense of more complex, more integrated)
Zombie→higher order cognitive functions impaired, lower (walking/breathing) still intact bc brainstem works
The Cerebral Cortex – the brain’s outer “bark” layer
The outer layer, resembles the bark layer of a tree
Different lobes→Frontal lobe, Parietal lobe , Temporal lobe, Occipital lobe (involved in vision) (all highly vascular)
→named by the bone located on top of that (first scientists were studying the skull (boundaries don’t necessarily
overlap with lobes)
Cerebral cortex has a distinct shape→consists of a bended and grooves surface wrapped around inside the skull
- Gyrus ≈ curve, bend (γύρος) e.g. superior temporal gyrus
- Sulcus = groove (Latin) e.g. central sulcus divides the frontal and parietal lobes
→thanks to the wrinkles big surface area in a small place →Total surface area: ~0.25 m 2 (non chiede)
- Fissure = deep sulcus e.g. lateral fissure divides temporal lobe from frontal and parietal lobe,
longitudinal fissure in between the hemispheres
Surface area of the cerebral cortex→surface of the book 4 times → ~40 x 62.5 cm, ~ 2- 4 mm, 4 x
Inside the brain (made of different tissues)
- Gray matter: nerve cells (no insulating layer) →outside of the cerebral cortex
- White matter: nerve fibers that connect all of brain regions (insulating layer=fatty myelin)→inside (white bc fat)
(Coronal section→dyslectic in the coronal plane→frontal view of the brain)
Regions made of a mixture of gray and white matter→reticular formation in the brainstem
Highest condensity of white matter in the Corpus callosum, structure that connects right and left hemispheres
Ventricle System
CSF flowing in the subarachnoid space, spinal cord and in the cavities (part of the ventricle system) 3D immage
4 interconnected cavities filled with cerebrospinal fluid (CSF) (1250ml) start in the:
- 1 st and 2 nd = lateral ventricles→one in each hemisphere, and then they drain in the:
- Third ventricle→diencephalon; between right and left thalamus, more or less in the middle of the brain
→3-4 ventricles connected by the cerebral aqueduct (tiny canal)
- Fourth ventricle→between the cerebellum and the pons (lowest one)
Fluid is generated throughout the day→we have 125 ml in total at any given time and it’s refreshed 4 times a
day, total amount produced is about 500ml and drains from the lateral ventricles in the bloodstream→direction of
flow is one way, sometimes there is a blockage of the ventricle system that usually occurs in the aqueduct (most
narrow part), →Waterhead syndrome in babies→skull expands in newborns, ventricle system blocked but the
3
, cells that produce CSF continue producing it→fluid blows up the ventricles and the skull starts expanding→can
result in brain damage if not treated immediately
Can happen also in elderly people→problem=you don’t see it from the outside+skull fixed, different symptoms
Technical term of waterhead syndrome is Hydrocephalus
Presumed function of CSF in the ventricles→maintaining brain metabolism, excretion of metabolic waste out of
the blood system (one way traffic system), cushion the brain
Recap Part 1 – Brain anatomy and physiology
→ meninges, arteries & stroke, cerebrum, cerebellum, brainstem (main structures under the meninges)
gyri, sulci and fissures, gray matter, white matter, ventricle system→to get out all the waste the gray tissue
→brain we see in books/laboratories is fixed brain→protein structures are fixated to make it easier to slice it into
small pieces (//egg, you have to boil it first, denature)→in operations the brain is unfixed and very soft (unfixed)
Part 2 – Brain anatomy and physiology
- Organization of the human nervous system
- Cells and Fibers – Gray and White matter
- Spinal cord, Brainstem, Forebrain
The human nervous system – organization
Anatomic organization→Nervous system:
-Central nervous system (CNS) →Brain+Spinal cord
-Peripheral nervous system (PNS) →Somatic nervous system+Autonomic n.s.+ (Enteric n.s.)
Functional organization→Nervous system:
-CNS (mediates behavior)→Brain+Spinal cord
-Somatic n.s. (transmits sensation, produces movement)→Cranial nerves (emerge from the brain)+Spinal nerves
-Autonomic n.s. (balances internal functions)→Sympathetic division (arousing)+Parasympathetic div. (calming)
-(Enteric nervous system) NB: Skip Enteric Nervous System (ENS) pp. 64-66
NB: knowledge of the classifications and structures is required for the exam!
memorize figure 2-14 p48
Ontogenetic organization (evolution of brain development) from the moment of fertilization to adulthood
Greek: έν = in κεφαλή =
head encephalon = “in the head” In Brain and Behavior, we discuss brain anatomy from the bottom up:
1. Spinal cord 2. Brainstem 3. Forebrain
NB: the higher a structure is located physically, the ‘higher’ its function. (higher in the sense of more complex,
more integrated, processes more information)
Cells and Fibers – wiring up the brain
Brain tissue consists of 2 types of nerve cells
- neurons, major brain functions - glia, support cells (lit. glue) provide structure
Cells are connected through nerve fibers (axons) (white matter consists of nerve fibers)
4
Chapter 1 Introduction
What is the brain? The brain is an organ, It consists of nervous tissue
The cells within this tissue are called nerve cells (neurons and glial cells)
What is behavior? Definition used in the book: Behavior consists of patterns in time
Examples: Movement, speech, attitude, blushing, thinking
→More practical definition: Any form of observable action or reaction of a person or animal in response to
external or internal stimuli→Most behaviors consist of a mix of inherited and learned actions.
Examples: Sucking reflex in newborns = inherited, Eating later in life = strongly influenced by learning/culture
This mixture varies considerably from species to species:
- Smaller, simpler nervous system→narrower range of behaviors that depend mainly on heredity, less
neuroplasticity→less learning processing possible
- Larger, more complex nervous systems→more complex behavioral patterns that depend on learning
The mind-body problem
Dualistic versus monistic philosophical views, Spiritualistic versus materialistic views (TL;DR: Nobody knows)
Brain and behavior
The brain is an organ, a physical object, living tissue. Behavior is action, not physical, but observable
This course is about the relationship between brain and behavior based on evidence from:
1. Evolution of brain and behavior in diverse animal species
2. Brain-behavior relationship in typical people
3. How brain changes in people with brain damage/dysfunction
A brief history of humankind
We do not descend from chimpanzees! → Men and chimpanzees do share a common Hominin ancestor
Hominins→ common ancestor originated ~ 5 million years ago, primates who walked upright, all hominins
evolved from this ancestor, humans only surviving hominin species
Some well-known ancestors (no details needed)
→at a certain point ancestor’s brain started to wave to have a bigger volume/size
-Australopithecus “southern ape” →originated ~ 4 million years ago in Africa (particularly south and east), brain
size ~400 cm 3 (0.4 kg), e.g.: australopithecus afarensis (Afar, Ethiopia): “Lucy”
-Homo habilis “handy man” →~2.5 – 1.5 million years ago, Africa, larger brain volume than australopithecus:
~800 cm 3 (0.8 kg), used simple stone tools, ate animal food
-Homo erectus “upright man” → ~1.5 million years ago, larger brain (900-1200 cm 3 – 0.89-1.18 kg), better
tools than homo habilis, migrated to Europe (Neanderthal) and Asia
-Homo sapiens “knowing man” →~120,000 years ago, originated in Africa, ~100.000 years ago, migrated to
Europe (Cro-Magnon, SW France), perhaps responsible for extinction of Neanderthal, cave art, the oldest are
aged ~30,000 years, brain volume about 1500 cm 3 (1.48 kg)
Evolution of human brain size
Encephalization quotient (EQ) = actual brain size / expected brain size (relative to body weight)
cat = average domestic animal EQ1, Australopithecus EQ2.5, Homo sapiens EQ 7.0 (way more than ancestor)
Our brain weight ~tripled in 4 million years time!
What is so special about the human brain? Modern humans have the largest brain size relative to body weight
How did our brain get so big? Theories:
- Lifestyle adjustments→social group size (~150) hunter-gatherer, eating fruit (more difficult to get than e.g. grass
but has more nutrients→to distinguish a green and a yellow banana you need color vision), use of fire (cooking),
more time for social interaction
- Efficient brain cooling→circulating blood functions as a radiator (like in a car engine, without cool system stops
working all together), enabled homo sapiens to maintain high metabolism (= more horsepower)→2% weight,
25% oxygen, 70% glucose
- Neoteny→(maturita’ sessuale) retention of juvenile features in the adult animal, adult humans closely resemble
the infants of gorillas and chimpanzees (e.g. large head relative to body size) +tend to explore more/curiosity
1
,Is a larger brain also a better brain (within species)? Answer: no
-Einstein's brain weighed only 1.2 kg, which is less than the average adult male brain (~1.4 kg)
-Men have ~10% more brain volume than women, but are not more intelligent
-Perhaps it is the (number of) connections between brain cells that matters?
NB: Most behavior is not innate but acquired during life and culturally determined!
Chapter 2 Brain anatomy and physiology
What is the nervous system’s functional anatomy?
This chapter describes the basic structure and function of the brain
Although the brain has structure, the brain is not a static organ; we are not born with a brain that remains
unchanged for the rest of our lives.
The brain is a plastic organ; neural tissue has the ability to adapt to the world→neural plasticity
Example: learning (without neural plasticity we wouldn’t be able to learn)
Navigating the brain – different orientation systems vedi bene immagine
- Brain-Body Orientation→illustrates brain structure location from the frame of reference of the human face
From Latin: “aimed towards or located” (arrows pointing different directions)
- Dorsal: dorsum→back (structures atop the brain or a structure within the brain are dorsal) ↑
- Ventral: venter→belly (structures toward the bottom of the brain or one of its parts are ventral)↓
- Medial: mediālis→middle (structures towards the brain’s midline are medial)→
- Lateral: laterālis side (structures located toward the sides are lateral)→
- Anterior: anterior before / in front of
- Posterior: posterior after / behind
- Spatial Orientation→illustrates brain structure location in relation to other body parts and body orientation
- Rostral: rostrum→beak (becco) =anterior
- Caudal: caudum→tail =posterior
- Superior: superior→above =dorsal
- Inferior: inferior→below =ventral
Animal brains are oriented similarly, but spinal-cord orientations may differ because many animals stand on ‘all
fours’. Compared with head orientation of a four-legged animal, dorsal and ventral take a 90* turn
counter-clockwise when describing the human or the bird brain→terminology shifted depending on the location
→Both ventral and dorsal seem to take a 90* turn because in the spinal cord ventral structures are still located
towards the belly side, but in the brain those structures are located toward the bottom side/below
- Anatomic Orientation→illustrates the direction of cut/section through human brain from the perspective of a viewer
Coronal section→cut in a vertical plane, from crown of the head down→frontal view of brain internal structures |
Horizontal section→cut falls along the horizon, looking down on the brain from above→dorsal view —
Sagittal section→cut lengthways from front to back, viewed from the side→medial view (sagitta=arrow, if you
want to kill someone you throw the arrow between their eyes→where the plane is, separate 2 hemispheres)
Brain protection – meninges & cerebrospinal fluid (CSF)
Meninges→triple layered membrane system that protects the brain from chemical and mechanical influences
from the outside, under the skull, before the brain tissue
1. Dura mater→outer layer, toughest one bc it’s double layered membrane (dura=tough mother), highly vascular
2. Arachnoid (+ Pia mater a.k.a leptomeninges, from λεπτός (Greek) leptos = thinner layers of the meninges)
if you take arachnoid apart it would look like a spider web (arachno), not highly vascular, consists of collagen and
other structures (elastic) but there are holes to allow veins from the dura mater to go through
3. Pia mater→highly vascular and sensitive, very soft (pia=soft), no receptors there (brain doesn’t have pain
receptors) headache→feeling not in the brain (it produces pain) but in the vascular system around it.
Subarachnoid space→space between arachnoid holes (below the arachnoid space)→filled with fluid CSF,
Cerebrospinal fluid, bc it runs between the brain (cerebrum) and the spinal cord (protects brain from concussion
when you move quickly, allows the brain to float around→brain tissue is very soft) average 125 ml (not much)
Triple layered system also around the spinal cord→in a small canal inside the bone structures (vertebra)
2
,Blood supply of the brain
- Vital to cool the brain efficiently→vaste network
- Brain=high metabolism organ (needs a lot of nutrients) and creates a lot of waste product→taken out by the
blood stream→venes system (waste out), arteries (oxygen in)
Cerebrovascular accident (CVA, ‘stroke’)
Brain can become life threatening bc it’s very vascular and the skull cannot expand (fixed structure) →every
additional fluid or tissue results in brain damage (compression/loss of oxygen supply)
-Ischemic CVA (80%) Blockage of blood vessel by clot (part of the brain is deprived of oxygen)→a clot blocks
blood flow to an area of the brain→treatment: make the blood thinner, make the clot out of the way
-Hemorrhagic CVA (20%)→Burst of vessel bleeding into the brain→bleeding occurs inside or around brain tissue
treatment: surgery to stop the bleeding (more serious, less common) if it happens on one side it affects also the
other→can lead to displacement of the midline of brain (brain squashed against the skull in the opposite side)
NB: behavioral consequences of stroke are extensively covered in subsequent course ‘Brain Dysfunction’
The brain from the outside Main structures visible from the outside:
1. Cerebrum (brain in latin)
2. Cerebellum (‘little cerebrum’)→little brain underneath the big brain
3. Brainstem→all the structures are built up the brainstem, involved in all kinds of cardiac functions (breathing,
blood pressure) without brainstem the brain doesn’t work at all bc needs to get the oxygen, but still it’s the
primitive portion of the brain →NB: the higher a structure is located physically, the ‘higher’ its function. (higher in
the sense of more complex, more integrated)
Zombie→higher order cognitive functions impaired, lower (walking/breathing) still intact bc brainstem works
The Cerebral Cortex – the brain’s outer “bark” layer
The outer layer, resembles the bark layer of a tree
Different lobes→Frontal lobe, Parietal lobe , Temporal lobe, Occipital lobe (involved in vision) (all highly vascular)
→named by the bone located on top of that (first scientists were studying the skull (boundaries don’t necessarily
overlap with lobes)
Cerebral cortex has a distinct shape→consists of a bended and grooves surface wrapped around inside the skull
- Gyrus ≈ curve, bend (γύρος) e.g. superior temporal gyrus
- Sulcus = groove (Latin) e.g. central sulcus divides the frontal and parietal lobes
→thanks to the wrinkles big surface area in a small place →Total surface area: ~0.25 m 2 (non chiede)
- Fissure = deep sulcus e.g. lateral fissure divides temporal lobe from frontal and parietal lobe,
longitudinal fissure in between the hemispheres
Surface area of the cerebral cortex→surface of the book 4 times → ~40 x 62.5 cm, ~ 2- 4 mm, 4 x
Inside the brain (made of different tissues)
- Gray matter: nerve cells (no insulating layer) →outside of the cerebral cortex
- White matter: nerve fibers that connect all of brain regions (insulating layer=fatty myelin)→inside (white bc fat)
(Coronal section→dyslectic in the coronal plane→frontal view of the brain)
Regions made of a mixture of gray and white matter→reticular formation in the brainstem
Highest condensity of white matter in the Corpus callosum, structure that connects right and left hemispheres
Ventricle System
CSF flowing in the subarachnoid space, spinal cord and in the cavities (part of the ventricle system) 3D immage
4 interconnected cavities filled with cerebrospinal fluid (CSF) (1250ml) start in the:
- 1 st and 2 nd = lateral ventricles→one in each hemisphere, and then they drain in the:
- Third ventricle→diencephalon; between right and left thalamus, more or less in the middle of the brain
→3-4 ventricles connected by the cerebral aqueduct (tiny canal)
- Fourth ventricle→between the cerebellum and the pons (lowest one)
Fluid is generated throughout the day→we have 125 ml in total at any given time and it’s refreshed 4 times a
day, total amount produced is about 500ml and drains from the lateral ventricles in the bloodstream→direction of
flow is one way, sometimes there is a blockage of the ventricle system that usually occurs in the aqueduct (most
narrow part), →Waterhead syndrome in babies→skull expands in newborns, ventricle system blocked but the
3
, cells that produce CSF continue producing it→fluid blows up the ventricles and the skull starts expanding→can
result in brain damage if not treated immediately
Can happen also in elderly people→problem=you don’t see it from the outside+skull fixed, different symptoms
Technical term of waterhead syndrome is Hydrocephalus
Presumed function of CSF in the ventricles→maintaining brain metabolism, excretion of metabolic waste out of
the blood system (one way traffic system), cushion the brain
Recap Part 1 – Brain anatomy and physiology
→ meninges, arteries & stroke, cerebrum, cerebellum, brainstem (main structures under the meninges)
gyri, sulci and fissures, gray matter, white matter, ventricle system→to get out all the waste the gray tissue
→brain we see in books/laboratories is fixed brain→protein structures are fixated to make it easier to slice it into
small pieces (//egg, you have to boil it first, denature)→in operations the brain is unfixed and very soft (unfixed)
Part 2 – Brain anatomy and physiology
- Organization of the human nervous system
- Cells and Fibers – Gray and White matter
- Spinal cord, Brainstem, Forebrain
The human nervous system – organization
Anatomic organization→Nervous system:
-Central nervous system (CNS) →Brain+Spinal cord
-Peripheral nervous system (PNS) →Somatic nervous system+Autonomic n.s.+ (Enteric n.s.)
Functional organization→Nervous system:
-CNS (mediates behavior)→Brain+Spinal cord
-Somatic n.s. (transmits sensation, produces movement)→Cranial nerves (emerge from the brain)+Spinal nerves
-Autonomic n.s. (balances internal functions)→Sympathetic division (arousing)+Parasympathetic div. (calming)
-(Enteric nervous system) NB: Skip Enteric Nervous System (ENS) pp. 64-66
NB: knowledge of the classifications and structures is required for the exam!
memorize figure 2-14 p48
Ontogenetic organization (evolution of brain development) from the moment of fertilization to adulthood
Greek: έν = in κεφαλή =
head encephalon = “in the head” In Brain and Behavior, we discuss brain anatomy from the bottom up:
1. Spinal cord 2. Brainstem 3. Forebrain
NB: the higher a structure is located physically, the ‘higher’ its function. (higher in the sense of more complex,
more integrated, processes more information)
Cells and Fibers – wiring up the brain
Brain tissue consists of 2 types of nerve cells
- neurons, major brain functions - glia, support cells (lit. glue) provide structure
Cells are connected through nerve fibers (axons) (white matter consists of nerve fibers)
4
