Lecture 1 Flashcards
The three different communication systems are
The nervous, endocrine and immune systems
Toward the nose
Rostral
Toward the tail
Caudal
Superior
Dorsal (sharks fin)
Central/not
Medial/lateral
Humans rostral/dorsal
Rotated 90 degrees
Close/far
Proximal = closer to the body's center Distal = further
Same/different side
Iplilateral/contralateral
3 planes
Coronal sections divide brain front to back (like a crown)
Sagittal sections are parallel to the midline
Horizontal sections divide from top to bottom
Meninges
Dura matter
Arachnoid
Pia
What is there none of on the PNS
Arachnoid matter
Ventricles
2 lateral
3rd and 4th
passes from the choroid plexus, circles the brain and the central canal of the spinal chord and is reabsorbed.
Cushions the brain
3 types of neurons
Sensory (afferent)
Motor (efferent)
Interneurons
Spine
Has reflex arcs and is like the information superhighway
Has protective reflex arcs but also has reflexes which maintain posture
Medulla
Has things important for life
HR, breathing
Pons
Sleep
Cerebellum
Motor control
Reticular formation
Arounsal
Hindbrain
Medulla
Pons
Cerebellum
RF
Midbrain
Tectum
○ Superior colliculi: visual processing, eye movements
■ Main key visual area for non-mammals
■ Just the start of the visual system in mammals
○ Inferior colliculi: auditory processing
● Tegmentum
○ Periaqueductal gray: lies around cerebral aqueduct
■ Experience of pain
○ Substantia nigra: black substance
The forebrain: Diencephalon
Contains the thalamus which is like a relay station and the hypothalamus which is responsible for many homeostatic processes
The forebrain: Telencephalon
Contains structures associated with higher functions:
The basal ganglia, limbic system and cerebral cortex
Basal ganglia
Receives input from the substantia nigra
Caudate nucleus
Putamen
Globus Pallidus
These work on voluntary movements and procedural movements. Eventually these allow habits
This makes things efficient but also as some are repeated for reward, can cause addiction
The limbic system
Emotion, learning and memory
Nucleus accumbens/septal area is involved in reward. It has connections to the Globus palladis so you can automate reward seeking behavior
The hypothalamus and amygdala are responsible for rewarding/scary input
The hippocampus is involved in memory
The cingulate gyrus does error monitoring
If you tried for a reward and failed, this would be important to remember so you try better next time
The cerebral cortex
As normal
Frontal lobe has input from all other, makes choice and then uses motor cortex to act accordingly
Connections between hemisphere
Corpus callosum - wrist thick
Anterior commissure
How many neurons
100 billion in a human
350 in a leech
Neuron structure
Cell body, nucleus, dendrites, axon, terminal bouton
Neurons are specialized for
Communication
Information processing
Glia are support cells
The neuron doctorine
Nervous system is composed of separate cells
Glia:neuron
Kandel said 10:1
Actually 1:1 across whole brain
10: 1 in hind and midbrain - most similar to the snails he studied
1: 4.5 in cerebellum
4: 1 in cerebral cortex
Neural cytoskeleton
Microtubules do…
Microfilaments do…
Neurofilaments provide support
Microtubules provide transport
Microfilaments may change the structure of the neuron in response to learning
3 configurations of neurons
where are their soma relative to their axon/dendrites?
Unipolar have one process leaving body which splits into two
Bipolar have 2 leaving (classic nerve)
Multipolar have many, usually many dendrites and an axon
Astrocytes
Structurally support neurons
Make the blood brain barrier
Isolate synapses so that only desired NT can interact with them
Collect molecules form the synapse
Have a role in neurogenesis
Extracellular/Intracellular fluid
ECF is like salt water
ICF has more K than CL or Na
Resting membrane potential maintained by
Negative peptides, Na/K pump
Forces on ions across neural membrane
Negative protein molecule - cant leave even though diffusion and electrostatic force wants it to
K+ Diffusion out, electro in
Cl- Electro out, diffusion in
Na+ Electro out, diffusion in
Action Potential
-70 mV Gets to threshold (typically -55mV) Na+ voltage gated channels open Na+ enters cell K+ channels open At +40mV Na+ channels close K+ leaves due to electrostatic force Returns to below resting in a refractory period K+ Channels close Na+/K+ pumps restore resting potential
Paracrine communication
Glands making chemicals that affect adjacent cells
Forebrain
Telencephalon - hemispheres + limbic system
Diencephalon - thalamus + hypothalamus
Midbrain
Tectum - (roof)
Tegmentum - covering - sub nig/ red nucleus (has motor fx)
Hindbrain
Cerebellum, medulla, pons
What makes a NT ex or inhib
The fx of its postsynaptic receptors
Ach
In muscles its excitatory
It does learning in the CNS
It is inhibitory in the autonomic system
Monoamines
Have their cell bodies in the brainstem and are distributed widely
Dopamine, adrenaline and noradrenaline
Dopamine
Reward
Planning
Learning and memory
Movement (parkinson’s)
Adrenaline
Increased alertness
Noradrenaline is made from adrenaline
Ideloamines
Serotonin and melatonin
Mostly inhibitory
Mood/eating/pain/sleep/arousal
Amino acids
Glutamate is typically excitatory
AMPA is fast conduction
NMDA does long term potentiation
Both are ionotropic
GABA is typically inhibitory
Peptides
Can include natural opiates among others
