Download PSB 4002 - Developmental Psychobiology Laboratory

Introduction to Biopsychology
[PSB 4002]
Professor Robert Lickliter
DM 260 / 305-348-3441
[email protected]
website: dpblab.fiu.edu
PSB 4002 / INTRODUCTION TO BIOPSYCHOLOGY
T TH 12:30 – 1:45 pm / Fall Semester, 2012
Instructor: Professor Robert Lickliter
DM 260
email: [email protected]
webpage: http://dpblab.fiu.edu
Teaching Associate: Josh Herrington
email: [email protected]
Teaching Assistant: Gina Bretos
email: [email protected]
Instructor’s Office Hours: Tuesdays & Thursdays: 2 – 3:30 pm (DM 260)
or by appointment (email or 305/348-3441)
Prerequisites: PSY 2020 / Introduction to Psychology
(or equivalent)
Required Text: Biological Psychology (3rd edition)
by Frederick Toates
Prentice Hall Publishers (2011)
On-Line Text Supplement: Brain Facts: A Primer on the Brain and Nervous System
Society for Neuroscience (pdf format)
(available on the course webpage: dpblab.fiu.edu)
Course Goals: The combined scientific disciplines of behavioral and cognitive
neuroscience, physiological psychology, and psychobiology are often referred to as
biopsychology. This survey level course is designed to examine a variety of topics in the
domain of biopsychology and to explore how their understanding contributes to a better
understanding of behavior. These topics include evolutionary theory, organization and
development of the nervous system, sensing and moving, maintaining homeostasis,
biological rhythms, emotions, learning and memory, thinking and consciousness, and
disorders of the brain and behavior. While the primary emphasis of the course will be to
develop a better understanding of the complex relationship between the nervous
system, the body, and the environment, we will also explore such topics as the roles of
evolution and development in nervous system structure and function, the biological
foundations of consciousness, and the importance of comparative psychology to
advances in biopsychology and the neurosciences.
Course Format and Grading: There are two sources of
information you will be responsible for: the class lectures and
your assigned textbook readings. Your grade in this course will
depend on your performance on three midterms and a final
exam. The three midterm exams and the final exam will consist of
both multiple choice and true/false questions and each exam will
count 50 possible points. The final exam will not be cumulative
and will essentially be a fourth midterm. The material to be
covered in each exam will include both assigned readings in your
text and lecture material presented in class. This means you are
responsible for both sources of course information, the assigned
readings and the classroom lectures. Your final letter grade in the
course will be directly translated from your overall percentage,
which will be derived from the total number of points you
accumulate across the three midterms and the final out of the
possible 200 points.
Important: Since this is a survey level course and we must cover a large amount
of material over the semester, the assigned textbook readings and the lecture
material presented in class will rarely overlap in their content, so class
attendance is necessary for you to do well in the course.
No makeup exams will be provided without a valid medical release. Plan to be in
class for all four scheduled exams. The date of the exams will be announced at
least two weeks prior, and your will receive sample study questions and the
lecture powerpoint slides one week prior to each exam.
Please arrive to lecture on time (12:30 pm). It is distracting to both the
instructor and other students if you arrive after lecture begins. I appreciate how
challenging it can be to be “unplugged” for more than an hour – nevertheless, I
expect you to turn off your cell phones, social media, etc. and actively
participate in the lecture and discussion while you are in the classroom.
All aspects of your coursework are covered by the University’s Honor System. In
regards to cheating and plagiarism - don’t do it!
Big Questions for Biopsychology
• How is the nervous system structured and
organized? How does the nervous system
develop?
• How does the nervous system process and
represent information about an organism’s
internal and external environment?
• How does the brain change during learning
and how are memories stored and retrieved?
How does the brain “think”?
Big Questions Continued
• What brain sites and activities underlie
emotions and feelings?
• What brain regions are
involved in language?
• How does
consciousness emerge
from the activities of a
nervous system?
What is inside your head?
• Your cerebral cortex, critical to higher brain
functions such as speech, thought, complex
movement patterns, goals and planning, has
about 10 billion neurons (nerve cells)
• Each of these neurons
receives connections from
other neurons at sites called
synapses. There are roughly
one million billion of these
connections in just in your
cerebral cortex
What is inside your head?
• If you set out to count these connections, one
connection (synapse) per second, you would
finish counting 32 million years after you
began counting.
• Another way of getting a feeling for this
complexity is to consider that a match head’s
worth of your brain contains about 1 billion
connections.
What is inside your head?
• If we consider how the connections between
neurons might be variously combined, the
number becomes hyperastronomical = 10
followed by millions of zeros.
• So we have our first clue as to what makes the
brain so remarkable, because when one adds the
chemical factors (neurotransmitters, hormones)
that influence neurons, as well as billions of glial
cells that influence neurons, we are talking about
the most complex material object in the known
universe.
Complexity
• Complexity turns out to be difficult to define,
but there are five attributes that in
combination seem to be involved:
large number of parts, large number of levels
large number of interactions among parts and
levels
hierarchical organization (of multiple levels)
non-linearity (not A  B C D)
Complexity
• and perhaps most important, emergent
properties (the whole is greater than the sum of
the parts)
• emergent properties cannot be predicted based
on knowledge of the properties of the parts alone
(example of water, H2O)
• emergence will turn out to be important in how
we make sense of higher order mental functions,
such as thinking, dreaming, and consciousness
Introduction to Biopsychology
[PSB 4002]
Professor Robert Lickliter
DM 260 / 305-348-3441
[email protected]
website: dpblab.fiu.edu
• The brain is a complex temporally
and spatially multi-scale structure
that gives rise to complex molecular,
cellular, and neuronal phenomena
that together form a basis for
perception, movement, cognition.
A Systems Perspective
The brain’s job is to facilitate an adaptive
dynamic pattern of interaction among
brain, body, and the world
In other words, neural systems are
elements of a larger system that includes
the rest of the organism’s body and also its
situation in and interaction with the
environment
The Notion of Embodiment
• Proposes that all aspects of perception, movement,
cognition, and interactions with the environment are
based on the coupling of a brain, in a body, in an
environment.
• Embodiment thus refers to bodily interactions with
the world, which is a necessary precondition for
subjectivity, emotion, value and meaning. These
interactions are based on (and constrained by) the
actual shape and physical capacities and limits of the
body.
The overall function of the brain is to be well
informed about 1) what goes on in the rest of
the body, 2) about what goes on in itself, and 3)
what goes on in the environment.
This regulatory process is about the business of
homeostasis. This involves (at the very least)
the coupling of a number of complex systems
beyond simply the nervous system.
The Coupling of Levels
Meeting the challenge of homeostasis involves:
•
•
•
•
•
central nervous system
autonomic (peripheral) nervous system
endocrine system
immune system
limbic system
Important Insight
• Given that the brain’s primary job is to
coordinate our dealings with the
environment, it is only in the context of
the brain, body, and environment
”system” that the function of the brain can
be understood
Neurons
• Like all cells of the body, neurons contain:
1. nucleus
2. cytoplasm
3. cell membrane
• However, neurons are specialized to communicate
with other neurons, muscles, glands, and other
internal organs. This is achieved via:
4. axon
5. dendrites
6. synapses
Neurons
•Axons are coated
(insulated) by myelin,
improving the flow of
electrical events from cell
to cell
emergence
• The manner in which complex phenomena
arise from a collection of interactions between
system components
• The outcome is more than the sum of its parts
Self-Organization:
•Self-organization is the process in which
pattern at the global level of a system
emerges from numerous interactions among
the lower-level components of the system.
•Thus, self-organization is an emergent
property of the system, rather than imposed
on the system by a pre-specified program or
set of instructions.
The “instructions” for development don’t
reside or exist anywhere – they emerge out
of how an organism lives and interacts with
its world
This insight leads us to a key insight in our
exploration of development: the
minimum unit of analysis for
understanding the nervous systems is the
coupling of a brain, in a body, in a
complex physical and social environment
Principles at Play
•
•
•
•
Self-organization
Reducing degrees of freedom
Sensitive periods
Developmental cascades
Introduction to Biopsychology
[PSB 4002]
Professor Robert Lickliter
DM 260 / 305-348-3441
[email protected]
website: dpblab.fiu.edu
Neurons
• Nerve cells are arranged in circuits and these are
arranged in neural networks
• There are three basic types of neurons:
– sensory neurons (input)
– motor neurons (output)
– interneurons (integration)
The Language of the Nervous System
• There are two forms or channels of
communication between neurons
– electrical: action potentials / an all or nothing
mode
– chemical: neurotransmitters / many and
modulated
The Language of the Nervous System
• There are two forms or channels of
communication between neurons
– electrical: action potentials / an all or nothing
mode
– chemical: neurotransmitters / many and
modulated
HOW NEURONS COMMUNICATE WITH EACH
OTHER CHEMICALLY
• The connection between two neurons is called
a synapse
• The neurons are not in direct physical contact
at the synapse but are separated by a small
gap called the synaptic cleft
• The neuron transmitting to another is called
the presynaptic neuron
• The receiving neuron is the postsynaptic
neuron
The Synapse Between a Presynaptic Neuron and
a Postsynaptic Neuron
HOW NEURONS COMMUNICATE WITH
EACH OTHER
•A Presynaptic
Terminal Releases
Neurotransmitter at
the Synapse
Central Nervous System (CNS)
Development in utero
• The human ovum is the largest cell in the
body, roughly 15 times larger than other cells,
but it is still no larger than a dot, much much
smaller that the period at the end of this
sentence.
• Over about 277 days of gestation, this one
fertilized cell will become trillions of cells, all
organized into the various glands, tissues,
organs, etc. that constitute our brain/body
system.
Development of the Nervous System
•The human genome has approximately 25,000
genes; the brain and spinal cord (CNS) has more
than 100 billion neurons. Clearly these numbers
indicate that nervous system development cannot
be simply “genetically determined” or prescribed.
• Gene expression is certainly involved in all
aspects of nervous system activity and the
behavior it supports, but many other factors and
processes must be at play
Development is an historical process
- initial conditions are powerful
- one thing leads to another
- what happens before guides and constrains
what can happen next
- particular pathways taken promote or make less
likely other pathways becoming available
Two Key Concepts in Making Sense of
Developmental Processes:
- self-organization
- loss of degrees of freedom
Self-Organization
Example: termite mounds
Loss of Degrees of Freedom:
The emergence of structure or pattern at any
point in a developmental sequence constrains
or limits what structure or pattern can occur
next.
Example: moving into a new apartment
Introduction to Biopsychology
[PSB 4002]
Professor Robert Lickliter
DM 260 / 305-348-3441
[email protected]
website: dpblab.fiu.edu
Midterm #1
• Thursday, September 13 (50 questions, multiple
choice and true/false format)
• sample study questions and powerpoint slides will
be available on the course website (dpblab.fiu.edu)
by Thursday, September 06
• Exam will cover textbook chapters 1, 3, and 6 and
lecture material through Tuesday, September 11.
Some perspective:
How old are you?
• As it turns out, not a straightforward question, as
the egg that developed following fertilization into
you was formed when your mother was a fetus –
so, at least from our mother’s side of the story,
you are as old as your mother.
• Human development before birth takes place in
three stages:
– zygote (first 2 weeks following conception)
– embryo (3-8 weeks following conception)
– fetus (8-38 weeks following conception)
• This process of prenatal development consists of a
cascade of many thousands of events – a cascade is
a succession of sequentially interdependent events,
with each event both triggered/influenced by the
event(s) preceding it and in turn itself acting as a
trigger for the next event(s).
• The cascade of prenatal development involves gene
expression events, chemical events, cellular events,
and their interactions. No surprise - these events are
influenced by factors both internal and external to
the developing embryo or fetus.
Key Processes in the Prenatal
Development of the Nervous System
1. Induction: cells on the ectoderm form a
neural tube, induced by cells below it in
the mesoderm
2. Proliferation: cell division results in an
incredibly rapid generation of tens of
thousands of cells per minute (during the
last half of gestation, over 250,000 cells
per minute)
Key Processes (continued)
3. Migration: moving from the neural tube
to the location where the cell will form a
part of the brain and become functional,
with help from glial cells
4. Aggregation: similar cells come together
by means of chemical and electrical
gradients produced by surrounding cells
Key Processes (continued)
5. Differentiation: sprouting axon and
dendrites by means of a growth cone
6. Circuit and Network Formation: connecting
synapses and axons and producing
neurotransmitters, thereby establishing
channels of communication across the NS
Circuit Formation
• During circuit formation, the axons of
developing neurons grow toward their target
cells and form functional connections.
– To find their way, axons form growth cones
at their tip which sample the environment
for directional cues.
– Chemical and molecular signposts attract or
repel the advancing axon, coaxing it along
the way.
Key Processes (continued)
7. Cell Death (apoptosis): based on patterns
of activity, experience, and use
DEVELOPMENT AND CHANGE
IN THE NERVOUS SYSTEM
8. The next stage of neural development, circuit pruning,
involves the elimination of excess neurons and synapses
• the developing nervous system refines its organization and
continues to correct errors by eliminating large numbers of
excessive synapses over time.
Prenatal Development of the Nervous
System
(summary of eight processes)
•Induction
•Proliferation
•Migration
•Aggregation
•Differentiation
•Circuit formation
•Cell death (apoptosis)
•Circuit pruning
Prenatal Development
Principles at Play
• Self-organization
• Reducing degrees of freedom
• Developmental cascades
Introduction to Biopsychology
[PSB 4002]
Professor Robert Lickliter
DM 260 / 305-348-3441
[email protected]
website: dpblab.fiu.edu
POSTNATAL DEVELOPMENT IN THE NERVOUS SYSTEM
•patterns of increased connectivity and organization, and synchronization of
activity
•increased number of dendrites, axon branches, synapses
•increased brain weight, increased thickness of cortex
•increasing degree of mylenation of axons
•all of these processes involve experience and activity-dependent competition and
selection
POSTNATAL DEVELOPMENT IN THE NERVOUS SYSTEM
• The neural networks of the brain are made during
development by cellular movement, extensions,
and connections
• The number of cells being made, dying, and
becoming incorporated into the nervous system is
huge. The entire situation is a dynamic one,
depending on signals, proteins, cell movement,
divisions, gradients, and cell death, all interacting
at many levels.
POSTNATAL DEVELOPMENT AND CHANGE
IN THE NERVOUS SYSTEM
• Stimulation continues to shape synaptic
construction and reconstruction throughout an
individual’s life.
• Much of the change resulting from experience in
the mature brain involves reorganization, a shift in
connections that changes the function of an area of
the brain.
Introduction to Biopsychology
[PSB 4002]
Professor Robert Lickliter
DM 260 / 305-348-3441
[email protected]
website: dpblab.fiu.edu
Nervous System
•The process of nervous system development is
cumulative (builds on itself) – events occurring in one
place require that previous events have occurred at
other places. In other words, brain structure and
function is
• historical
• situated
• contingent
Nervous System
•The KEY mechanisms involved in the process of
nervous system development are :
• competition
• selection
Nervous System
•The notion of experience-dependent development
-interactions with the environment modify gene
activity and expression and shape the course of
nervous system construction and modification
Postnatal Maternal Care in Rodents
Variations in care lead
to variations in
offspring phenotype
stress
responsivity
response to
reward
natural variations in
maternal care
High vs. Low
levels of licking/grooming
stimulation of pups
cognition
social
behavior
Real Time/ Developmental Time
•Real Time: firing patterns of diverse neural networks;
cell groups transmit information to each other;
activities of brain regions cohere or synchronize it real
time (we can now observe this with neural imaging
technology)
•Developmental Time: increasing specification of
structure; increased levels of organization based on
real time use. The overall cumulative effects of
activity and experience over time sculpts the nervous
system.
THE CENTRAL NERVOUS SYSTEM
• The central nervous system is arranged in a
hierarchy.
– As you ascend from the spinal cord through the
hindbrain and midbrain to the forebrain, the
neural structures become more complex and so
do the behaviors they control.
• The hemispheres are divided into four lobes –
frontal, parietal, occipital, and temporal – each
named after the bone of the skull above it.
Same Basic Design:
Genes (at least most)
Neurons and neural networks
Action potentials
Neurotransmitters
Ion channels
Hormones
The Brain
•The human brain is mostly distinguished from the
brains of other mammals, including other primates, by
the number of brain cells and the patterns of their
interconnections.
•The two regions of the brain that differ most between
humans and other primates are the frontal and parietal
lobes of the cortex. These structures are 5-8 times
larger in humans and remain highly open to shaping by
the environment and experience for 5 to 10 times
longer during postnatal development than other
primates.
Midterm #1
• Powerpoint slides and sample study questions
will be available on the course website
(dpblab.fiu.edu) on
• Exam will cover textbook chapters 1, 3, 5 and
lecture material through
What determine the structure and behavior of
a system are particular relational conditions of
the system and the environment over time
Self-organization can be contrasted to the
notion of organization by design.
Example: A car or a computer - in order to
work, every detail must function according
to a preconceived plan or design.