PSYC 310 Lecture Notes - Lecture 4: Adrenergic Receptor, Adenylyl Cyclase, Basal Ganglia
7 May 2018
School
Department
Course
Professor
PSYC 318
Behavioural Neuroscience II
January 8th, 2018
Lecture 1/24: Introduction
• 20-30 papers from past 5 years: research articles from high-impact journals (no
textbook) from famous scientists and well-funded labs that will be posted on myCourses:
article and supplementary information (if you have particular questions)
o Don’t need to read articles in full ahead of time, but download paper off
myCourses and read abstract/introduction for general sense. After going through
paper in class go back and read the paper.
• Dr. Jonathan Britt: STBIO N8/9 jonathan.britt@mcgill.ca Office hours Thursdays 10-
11am and TA: TApsych31[email protected]
• Last 6 lectures in course taught by Wayne Sossin, he spends more time on cell biology
of learning and memory: kinases, protein translation, etc.
o TAs have cell biology review conferences for students during this time
• Course description
o Familiarize w/ ways scientists explore neurological basis of behavior
o Modern techniques, principles of neural circuits/physiology
o Social behavior, reinforcement learning, decision making, drug addiction, hunger,
anxiety, aggression, mating, sleep and memory
o Most papers to be presented are featured in popular press as well
▪ Newspaper articles highlight in an abstract way what scientists are
working on, but doesn’t offer any serious analysis of what the scientists
involved actually did
o Tests will be on the material covered in class: it is possible to get an A without
actually reading any of assigned readings, therefore
o Two in-class exams: Feb 7, Mar 14 and both are cumulative but focused on what
was most recently covered, preferentially. (25% each midterm, 50% final exam)
▪ Exams are mandatory, no makeup exams
o Three grad student TAs with office hours by appointment: Christopher Lafferty,
Jesse Mendoza, Matteo Bernabo and two undergraduate TAs Andrea Terceros
and Joseph Kates Rose with office hours by appointment
▪ Will host formal review conference sessions spread out throughout the
semester: review sessions every 3-4 classes, locations and times TBD
but on Tuesdays (jan 16, 30, feb 6, 20, mar 13, 20, apr 5, 11) see slides
for specific topics to be covered in them
• Your instructor
o Jonathan Britt, Department of Psychology (Behavioural Neuroscience)
o Lab in Stewart Bio studying motivational processes and reinforcement learning:
dopaminergic signaling in basal ganglia, using modern techniques like calcium
imaging and ontogenetics in different behavioral tasks on rodents
• We will discuss modern circuit mapping techniques: wiring of the brain
o We don’t understand exactly cell types in brain and how they are connected to
one another at this point: it is extremely difficult to figure out basic wiring diagram
of the brain.
o And we will then discuss how brain actually works: when specific neural circuits
are active and when they are consequential
o Different levels of learning and memory: circuit level, cellular level
find more resources at oneclass.com
find more resources at oneclass.com
• Learning & Memory
o Little pre-programmed knowledge at birth, we are evolved to focus on certain
stimuli through evolution but there are only a few instincts we are actually born
with
▪ Most other purposeful behaviors seem to be randomly generated at birth
▪ Learning how to move and engage with environment dictated initially be
reinforcement learning principles
▪ Reinforcement learning: how does animal judge successful behavior and
how does that shape future of that behavior?
o More elaborate decision-making goes on in the brain: thoughtful, reflective
decisions relying on intricate world models
▪ These cognitive actions often lead us to make the correct choice despite
never being in the situation before, by our general sense of how the world
works
▪ Cognitive maps of the world we use to guide our behavior in an intelligent
manner
• Basic neuroscience & cell biology principles
o Neurons are cells…
o What does a neuron consist of?
▪ Organized arrangements of hydrogen, oxygen, carbon
▪ 15% nucleic acids (RNA and DNA)
• store information on how to make proteins
▪ 50% amino acids (proteins)
• strings of amino acids create proteins dictated by DNA/RNA
instructions
• DNA stored in nucleus of eukaryotic cells, transcribed DNA ->
RNA -> protein which then do some function in the cell
• Humans have about 20,000 protein-coding genes in their genome
o Many genes can make variants of proteins
o Proteins typically characterized by their function: enzymes,
kinases, phosphatases, receptors, signaling molecules,
etc.
o They have regulatory, transport functions, make up
microtubules, involved in defense/storage
o When we talk about receptors, kinases, signaling
molecules, these are all proteins that can be encoded for
in DNA
o Important for considering cell manipulation to derive
insights on how brain works
o If we create foreign DNA and give it to cells we can get
them to start doing things they’ve never done before and
through this we can test our predictions on brain
functioning
▪ 10% lipids (cell membrane)
o Protein synthesis
▪ All eukaryotic cells have a nucleus in the cell body (soma) where there
are chromosomes, made of strands of DNA
• A gene is a functional unit of chromosome that encodes a specific
protein
• Humans have 20,000 coding regions
find more resources at oneclass.com
find more resources at oneclass.com
• When a gene is read it unravels in the nucleus, translated into
RNA so that information can leave nucleus
• Pieces of RNA float around the cell: one way to regulate cell
function is to see if DNA is transcribed into RNA, and once RNA is
made is it translated into protein or naturally degraded?
• Cells choose what RNA gets turned into protein
o Meets with ribosome, translated into string of amino acids
to make a protein
o Basics of the cell
▪ Soma and cell body are synonyms: it is where the nucleus is
▪ Where a neuron is located: where the cell body or nucleus is
• Hippocampal neuron: its cell body is located in the hippocampus
• Neurons have long processes that go far beyond cell body
• Dendrites and axons, often axons cross over brain regions or
extend to spinal cord, hindbrain, etc.
• Just tells us where body is but not where it projects to or who it
communicates with
▪ Microtubules important for protein transportation because neurons are so
long – lots of disorders associated with failure of this transport process
▪ Neurons have dendrites: tree-like extensions off cell-body that integrate
information, they have receptors for hundreds of different types of
signaling molecules
• Tons of protein-sensitive receptors
• Integrate lots of information: changes in ion conductance across
membrane that change the membrane voltage
• Cell is trying to answer: should it fire an action potential or not?
o Decision made initially at the axon hillock: concentration of
voltage-gated sodium channels
o Membrane can become hyper/de polarized
o If threshold of membrane potential is reached at axon
hillock than an action potential is started
▪ Release of synaptic vesicles, neuron is
communicating downstream
• Axon covered in myelin
• Axon terminals release signaling molecules typically into synapse
(junction between action terminal and membrane of downstream
neuron)
▪ Synapses can form anywhere
• Synapses can form between axon terminals and dendrites,
dendritic spines, the soma, other axon terminals
• In one paper to be covered next class: oxytocin signaling seems
to cause animals to find social interactions pleasurable, mice form
long-lasting social bonds
• If you block oxytocin signaling in body animals (rodents) don’t
form these bonds
• Complex synaptic interactions discussed in this paper ^
• At presynaptic terminals, electrical signals are transformed into
chemical signals
o Neurons are sensitive to many things in the environment,
but typically only release a couple different kinds of
find more resources at oneclass.com
find more resources at oneclass.com
