Lecture 1 (07-02)
Central nervous system: brain and spinal cord
peripheral nervous system: nerves related to touch for example
The brain is divided into four lobes (curved structure)
- Gyrus (hills): higher areas
- Sulcus (grooves): open areas in between
- Fissure: deeper groove, which separates lobes from each other
Size of the brain has no correlation with being smart, may vary from person to person
Phrenology: the idea that the shape of the skull tells you something about characteristics and personality
(old); there are certain areas on the brain that are connected to certain functions (new)
Broca: came up with idea that functions were coupled to areas in the brain; patient was unable to talk,
had a large damage (due to stroke or lesion; brain cells died) in region connected to speaking (Broca’s
area; motor aphasia); Wernicke’s area can speak (but not in a logical manner), cannot understand
language; dyslexia (sensory aphasia)
Brain imaging:
- CT scan (computed tomography); can see whether area is affected or not (not related to activity,
related to structure); reveals gross organization of white and gray matter, and positions of
ventricles
- MRI scan (magnetic resonance imaging); can see the structure more clearly (not related to
activity, related to structure)
- PET scan (positron emission tomography); activity is visible
- fMRI scan (functional magnetic resonance imaging); 3D structure of the brain, activity is visible
In serial killers: area in front of brain less active (prefrontal cortex), has dark patches
Anatomical references
- Sagittal (brain divided into equal left and right halves), coronal (perpendicular to ground and to
sagittal plane; cuts brain into anterior and posterior parts) and horizontal (parallel to the ground)
- Rostral (anterior): head; caudal (posterior); tail
- Ventral is the side of the belly, dorsal is the side of the back
Central nervous system consists of:
- Cerebrum: rostral-most; split into cerebral hemispheres; left hemisphere controls right side of
body
- Cerebellum: movement control center; right side of cerebellum controls right side of body
- Brain stem: relays information; regulates vital functions (breathing, consciousness, temperature)
- Spinal cord: communicates with the body via spinal nerves
Electrical activity is responsible for connections in the brain; memory is strengthening of connections
- Grey matter: dendrites and cell bodies
- White matter: axons
Other cells next to neurons: scavengers ‘clean up the mess’ of a stroke or brain damage
,The ventricular system: production CSF (cerebrospinal fluid) 500 ml/day (washes and protects the brain);
2 lateral ventricles, 3rd and 4th ventricle; pumped through cerebral aqueduct (when blocked, body
cannot get rid of excess CSF); choroid plexus generates CSF
→ enlargement of lateral ventricles sign of schizophrenia (indicates a loss of brain tissue)
- CSF is present in the subarachnoid space, which is the space between the pia mater and
arachnoid membrane (outermost membrane is the dura mater)
Neurophilosophy: the neuron as basic unit which can be studied by neuroanatomical techniques; no
mind-brain separation;
- Nissl staining; thought dendrites and cell bodies of neurons were not connected → basic dyes
can be used to stain nuclei of all cells as well as clumps of material surrounding nuclei of neurons
- Golgi staining; convinced that they were connected → one cell body visible with thin tubes that
radiate from it
Axons usually very long (up to 1 m) and dendrites very short (2 mm)
- Cajal said that dendrites and axons belong to one soma/neuron; proved that neurons are not
continuous with each other, but communicate by contact
One axon coming from a cell body
Axons collaterals; axons activate many other neurons
Neurites: axons + dendrites (all connections)
- Colocalized: yellow colour (in fluorescent labeling)
Classification based on neuronal structure
- Unipolar: neuron with a single neurite
- Bipolar: neurons with two neurites
- Multipolar: neurons with more than two neurites (most neurons are multipolar)
- Stellate cells (star shaped)
- Pyramidal cells (pyramid shaped)
- Spiny: neurons with dendrites that have spines
- Aspinous: neurons with dendrites without spines
Twice as many glia cells (astrocytes) as neurons; fill space not occupied by neurons or blood vessels
,Lecture 2 (08/02)
Amnesia: a serious loss of memory and/or the ability to learn
- Retrograde: memory loss for events prior to trauma; older memories usually stronger
- Anterograde: inability to form new memories
Patient H.M most important study subject in biology; had a biking accident, and cracked his skull →
severe seizures (daily), blackouts, loss of bodily functions; met Dr. William Skoville, who removed the
hippocampus (region in the limbic system) → no more seizures, no change in personality, I.Q. improved +
loss of memories from 2 years before surgery (retrograde), unable to form new memories (anterograde);
working memory intact
How a memory is formed: memory acquisition → memory storage (short term changes to long term
memory, which could turn into long lasting memory)→ memory retrieval
- H. M. can repeat digits, provided that the time between learning and recall is within the duration
of short term memory
- In block-tapping test, he could tap 5 blocks
- Good retention in mirror drawing task; no recollection of having performed it before → brain
can get better at retention tasks without the hippocampus, but it cannot retain most of the tasks
when it is performed later
- Explicit memories are mostly affected (conscious memories, remembering facts), implicit
memories were not (unconscious memories)
Nonmatching-to-sample; subject needs to choose a novel object, with a delay (waiting a while before
test) → the more difficulties the longer the retention delay (mostly in medial temporal lobe lesions;
hippocampus, amygdala, prefrontal cortex)
In DNMS, recognition memory is required, because it involves the ability to judge whether a stimulus has
been seen before
Scientific contributions H.M. case
- Medial temporal lobe critical for memory
- STM, LTM and remote memory
- H.M. had severe memory consolidation problems for certain forms of memory
- Memories may exist but cannot be recalled; H.M can exhibit a skill he did not know he had
learned
Patient R.B. : damage to area CA1 of the hippocampus (no surgery to remove it) → Rey–Osterrieth test;
draw something, after 15 minutes draw it again; hippocampal damage is sufficient to produce amnesia in
explicit memories, were not able to reproduce drawing well
Clive Wearing: was able to play piano (do not need hippocampus for processing notes and motor
function); not able to recall information from seconds ago; does not remember ever seeing doctors,
although he met many of them; recognizes wife (probably because of strong emotional connection);
explicit memories affected
, Korsakoff’s syndrome (seen in alcoholics, lack of vitamin B): is able to do arithmetics, cannot recall how
long he has been in the hospital, can recall where he came from, but has not been there in ten years (can
recall stuff from a long time ago, but not stuff that happened in the past few years due to anterograde)
- Hypothalamic mammillary bodies not a factor
- Damage in thalamic mediodorsal nuclei is likely a factor in korsakoff syndrome
Amnesia of Alzheimer’s disease: major anterograde and retrograde amnesia in explicit memories, also
implicit memories are impacted (hippocampus gone, shrinkage);
What causes the damage seen in Alzheimer’s disease: impaired cholinergic system, medial temporal lobe
and prefrontal cortex involved, damage starts at bottom of brain in the hippocampus, and then diffuses
Concussions can also cause amnesia → causes retrograde amnesia for period before the blow and some
anterograde amnesia afterward
Phineas Gage’s prefrontal cortex was damaged when it was impaled, which changed his personality;
lobotomy: disruption of connections in the prefrontal cortex (to solve, psychological problems,
homosexuality, communism)
Hippocampal learning in mice and rats
- Morris water maze: mice learn that there is a platform, where it is, and then they can go straight
to it (need hippocampus to navigate themselves to platform)
Hippocampus (spatial learning), visual system (for orientation in the room) and motor cortex and
cerebellum (swimming steering coordination) are all important for learning this test
Control group also underwent surgery with another irrelevant part of the brain to see whether
the surgery itself had an effect on the outcome
- Behavioural flexibility (first affected by aging) is updating previously acquired information
Declarative memory (explicit): memory of facts and events → more easy to forget than implicit
memories; types of declarative memory:
- Long-term memory: memories that can be recalled a while ago after they have formed
- Short-term memories: vulnerable to disruption, disappear quickly
Memories go from ST to LT through memory consolidation
- Working memory: limited capacity, need for repetition, short duration
Nondeclarative memories (implicit); procedural: memory of skills, habits and behaviours
Central nervous system: brain and spinal cord
peripheral nervous system: nerves related to touch for example
The brain is divided into four lobes (curved structure)
- Gyrus (hills): higher areas
- Sulcus (grooves): open areas in between
- Fissure: deeper groove, which separates lobes from each other
Size of the brain has no correlation with being smart, may vary from person to person
Phrenology: the idea that the shape of the skull tells you something about characteristics and personality
(old); there are certain areas on the brain that are connected to certain functions (new)
Broca: came up with idea that functions were coupled to areas in the brain; patient was unable to talk,
had a large damage (due to stroke or lesion; brain cells died) in region connected to speaking (Broca’s
area; motor aphasia); Wernicke’s area can speak (but not in a logical manner), cannot understand
language; dyslexia (sensory aphasia)
Brain imaging:
- CT scan (computed tomography); can see whether area is affected or not (not related to activity,
related to structure); reveals gross organization of white and gray matter, and positions of
ventricles
- MRI scan (magnetic resonance imaging); can see the structure more clearly (not related to
activity, related to structure)
- PET scan (positron emission tomography); activity is visible
- fMRI scan (functional magnetic resonance imaging); 3D structure of the brain, activity is visible
In serial killers: area in front of brain less active (prefrontal cortex), has dark patches
Anatomical references
- Sagittal (brain divided into equal left and right halves), coronal (perpendicular to ground and to
sagittal plane; cuts brain into anterior and posterior parts) and horizontal (parallel to the ground)
- Rostral (anterior): head; caudal (posterior); tail
- Ventral is the side of the belly, dorsal is the side of the back
Central nervous system consists of:
- Cerebrum: rostral-most; split into cerebral hemispheres; left hemisphere controls right side of
body
- Cerebellum: movement control center; right side of cerebellum controls right side of body
- Brain stem: relays information; regulates vital functions (breathing, consciousness, temperature)
- Spinal cord: communicates with the body via spinal nerves
Electrical activity is responsible for connections in the brain; memory is strengthening of connections
- Grey matter: dendrites and cell bodies
- White matter: axons
Other cells next to neurons: scavengers ‘clean up the mess’ of a stroke or brain damage
,The ventricular system: production CSF (cerebrospinal fluid) 500 ml/day (washes and protects the brain);
2 lateral ventricles, 3rd and 4th ventricle; pumped through cerebral aqueduct (when blocked, body
cannot get rid of excess CSF); choroid plexus generates CSF
→ enlargement of lateral ventricles sign of schizophrenia (indicates a loss of brain tissue)
- CSF is present in the subarachnoid space, which is the space between the pia mater and
arachnoid membrane (outermost membrane is the dura mater)
Neurophilosophy: the neuron as basic unit which can be studied by neuroanatomical techniques; no
mind-brain separation;
- Nissl staining; thought dendrites and cell bodies of neurons were not connected → basic dyes
can be used to stain nuclei of all cells as well as clumps of material surrounding nuclei of neurons
- Golgi staining; convinced that they were connected → one cell body visible with thin tubes that
radiate from it
Axons usually very long (up to 1 m) and dendrites very short (2 mm)
- Cajal said that dendrites and axons belong to one soma/neuron; proved that neurons are not
continuous with each other, but communicate by contact
One axon coming from a cell body
Axons collaterals; axons activate many other neurons
Neurites: axons + dendrites (all connections)
- Colocalized: yellow colour (in fluorescent labeling)
Classification based on neuronal structure
- Unipolar: neuron with a single neurite
- Bipolar: neurons with two neurites
- Multipolar: neurons with more than two neurites (most neurons are multipolar)
- Stellate cells (star shaped)
- Pyramidal cells (pyramid shaped)
- Spiny: neurons with dendrites that have spines
- Aspinous: neurons with dendrites without spines
Twice as many glia cells (astrocytes) as neurons; fill space not occupied by neurons or blood vessels
,Lecture 2 (08/02)
Amnesia: a serious loss of memory and/or the ability to learn
- Retrograde: memory loss for events prior to trauma; older memories usually stronger
- Anterograde: inability to form new memories
Patient H.M most important study subject in biology; had a biking accident, and cracked his skull →
severe seizures (daily), blackouts, loss of bodily functions; met Dr. William Skoville, who removed the
hippocampus (region in the limbic system) → no more seizures, no change in personality, I.Q. improved +
loss of memories from 2 years before surgery (retrograde), unable to form new memories (anterograde);
working memory intact
How a memory is formed: memory acquisition → memory storage (short term changes to long term
memory, which could turn into long lasting memory)→ memory retrieval
- H. M. can repeat digits, provided that the time between learning and recall is within the duration
of short term memory
- In block-tapping test, he could tap 5 blocks
- Good retention in mirror drawing task; no recollection of having performed it before → brain
can get better at retention tasks without the hippocampus, but it cannot retain most of the tasks
when it is performed later
- Explicit memories are mostly affected (conscious memories, remembering facts), implicit
memories were not (unconscious memories)
Nonmatching-to-sample; subject needs to choose a novel object, with a delay (waiting a while before
test) → the more difficulties the longer the retention delay (mostly in medial temporal lobe lesions;
hippocampus, amygdala, prefrontal cortex)
In DNMS, recognition memory is required, because it involves the ability to judge whether a stimulus has
been seen before
Scientific contributions H.M. case
- Medial temporal lobe critical for memory
- STM, LTM and remote memory
- H.M. had severe memory consolidation problems for certain forms of memory
- Memories may exist but cannot be recalled; H.M can exhibit a skill he did not know he had
learned
Patient R.B. : damage to area CA1 of the hippocampus (no surgery to remove it) → Rey–Osterrieth test;
draw something, after 15 minutes draw it again; hippocampal damage is sufficient to produce amnesia in
explicit memories, were not able to reproduce drawing well
Clive Wearing: was able to play piano (do not need hippocampus for processing notes and motor
function); not able to recall information from seconds ago; does not remember ever seeing doctors,
although he met many of them; recognizes wife (probably because of strong emotional connection);
explicit memories affected
, Korsakoff’s syndrome (seen in alcoholics, lack of vitamin B): is able to do arithmetics, cannot recall how
long he has been in the hospital, can recall where he came from, but has not been there in ten years (can
recall stuff from a long time ago, but not stuff that happened in the past few years due to anterograde)
- Hypothalamic mammillary bodies not a factor
- Damage in thalamic mediodorsal nuclei is likely a factor in korsakoff syndrome
Amnesia of Alzheimer’s disease: major anterograde and retrograde amnesia in explicit memories, also
implicit memories are impacted (hippocampus gone, shrinkage);
What causes the damage seen in Alzheimer’s disease: impaired cholinergic system, medial temporal lobe
and prefrontal cortex involved, damage starts at bottom of brain in the hippocampus, and then diffuses
Concussions can also cause amnesia → causes retrograde amnesia for period before the blow and some
anterograde amnesia afterward
Phineas Gage’s prefrontal cortex was damaged when it was impaled, which changed his personality;
lobotomy: disruption of connections in the prefrontal cortex (to solve, psychological problems,
homosexuality, communism)
Hippocampal learning in mice and rats
- Morris water maze: mice learn that there is a platform, where it is, and then they can go straight
to it (need hippocampus to navigate themselves to platform)
Hippocampus (spatial learning), visual system (for orientation in the room) and motor cortex and
cerebellum (swimming steering coordination) are all important for learning this test
Control group also underwent surgery with another irrelevant part of the brain to see whether
the surgery itself had an effect on the outcome
- Behavioural flexibility (first affected by aging) is updating previously acquired information
Declarative memory (explicit): memory of facts and events → more easy to forget than implicit
memories; types of declarative memory:
- Long-term memory: memories that can be recalled a while ago after they have formed
- Short-term memories: vulnerable to disruption, disappear quickly
Memories go from ST to LT through memory consolidation
- Working memory: limited capacity, need for repetition, short duration
Nondeclarative memories (implicit); procedural: memory of skills, habits and behaviours
