Exam 1 Review Flashcards
Psychology
the scientific study of behavior using the scientific method
Psychobiology
- study of how the brain affects behavior
- biological psychology/behavioral neuroscience/ –> study of biological bases of psychological processes and behavior
What psychological processes and behaviors does biopsych study?
- learning
- memories
- emotions
- language
- movement
- consciousness
- thinking
- sleep
- dreams
- addiction
- hunger
- sex
What is Central Nervous System (CNS)
- brain and spinal cord
- encased within the skull and spinal column
What is Peripheral Nervous System (PNS)
- made up of nerve tissue located outside of the brain and spinal cord
Basic premise of brain, behavior, psychological processes
study the brain and we can understand the underlying biological mechanism of psychological processes and behaviors
Francis Crick –> “Astonishing Hypothesis”
“…that ‘You’, your joys and your sorrows, your memories and your ambitions, your sense of personal identity and free will, are in fact no more than the behavior of a vast assembly of nerve cells and their associated molecules”
- what we are able to do and what we are is the result of the activity of the brain
Early Perspectives of Mental Function
- some civilizations/ ancient Egyptians: gave little importance to brain
- other civilizations: thought brain was a “gift from God”
Early Perspectives of Mental Function (Aristotle)
- took psychology as the science which investigates the soul and its properties
- believed heart was center of sensation, movement, and responsible for mental abilities and emotions (not brain)
- believed was a cooling system for hot blood from heart
The Mind-Body Problem/Dualism
- Rene Descartes defended Dualism
- Dualism: The belief that the body and brain are physical (can be studied) but the mind is not physical (cannot be studied)
- mind and body/brain are separate from each other
- mind = consciousness, imagination, perception, judgment, etc
- Descartes also argues that our minds are immaterial and nonphysical (not bound to our body)
Concept of Reflexes
- Descartes thought brain and body worked like a machine, responding to things in our environment
- proposed concept of spinal reflexes and their neutral pathways
- explaining how body can perform automatic actions in response to external stimuli w/o conscious thought
- used idea of “animal spirits” flowing throught nerves, w/ pineal gland as central processing point –> (seat of the soul; third eye)
- actions of body are reflective in nature, but actions of mind are meaningful, conscious, and voluntary
Arguments supporting Dualism
- the creativity and spontaneity of human action cannot be replicated by machines or nonhumans (he lived in 17th century)
Descartes asked “what can we be sure of”
- he believed in a GOD, but how could he be sure there is one?
- he believed he lived in a rich country, but how did he know he was not being fooled?
- he believed he had a family, but how did he know he was not being fooled?
- what if an evil demon has tricked him into believing he is experiencing things that are not real?
Dualism - Arguments supporting it
- Descartes believed having a body was also uncertain
- one thing he could not doubt was the fact that he was thinking
“I think, therefore I am”
- Having a body is uncertain, but having a mind is not (cannot self-refute)
- concluded “I knew I was a substance, the whole essence or nature of which is to think, and that for its existence, there is no need of any place nor does it depend on any material thing. That is to say, the soul by which I am, when I am, is entirely distinct from body”
Dualism makes sense to us because…
- enmeshed in our language
–> ex. we say “my car”, “my house” to identify material possessions, but we extend that to our brain and body.
–> We own our brain and our body…so we say “my arm”, “my heart”, “my body”,”my brain”. - Dualism shows up in our intuitions about personal identity
–> we can imagine that someone can be the same person even if they go radical changes in their body
Dualism is common sense
we can also imagine more than one person in single body
–> Dissociative identity Disorder (Multiple personality disorder)
–> possession
- most people in the word believe that the self will survive after death
–> cultures differ in terms of where your self goes… but share the idea that what you are is separable from this physical thing you carry around…and the physical thing that you carry around can be destroyed while you live on
–> IMPLIES THE BODY IS SEPARATE FROM THE MIND
Introspection (early perspectives on mental function)
- a process by which someone examines their own conscious experience as objectively as possible
- also called “internal perception”, coined by the v first “psychologist” William Wundt
Structuralism (early perspectives on mental function)
- proposed by Wundt’s student, Edward Titchener, focusing on the mental processes themselves, instead of their function
Functionalism (early perspectives on mental function)
- developed by William James (first American psychologist), it focused on how mental activities helped an organism fit into its environment
Based on Darwin’s theory of evolution
Back to Crick’s hypothesis…
- Today: scientific consensus is dualism is wrong/ no “you” separable from your brain
- mind is what your brain does (monism)
–> belief that the world consists only of matter and energy and the mind must be part of it
–> mind and body can be studied: they are either matter or energy
Why is Dualism rejected?
- unscientific…“the mind is non-physical”…yet the mind and body interact
- dualism does not explain how or where the mind and body interact
Brain Function and Mental Life
- Evidence supporting the role of the brain in our mental life has accumulated over the years
–> disease can affect mental ability
–> chemicals can affect how we think
–> injury to head can change our mental ability
–> and now we can see using imaging techniques a correspondence between our mental life and our brain –> track blood flow (fMRI)
Mind = Brain
- Today: Scientific consensus is that all of mental life, including consciousness, emotions, choice, morality, etc. are the result of brain activity
- Goal of Biological Psych: to explain how brain can give rise to thought, emotion, memory, and what we think of as human behaviors and psychological processes by understanding how the brain works
- this is the underlying assumption in this class
Levels of Analysis
Three main approaches to studying brain - behavior relationship
–> somatic intervention - manipulating the body and/or the brain may affect behavior
–> behavioral intervention - manipulating the behavior may affect the body and/or the brain
–> correlation - measure how closely the body/brain and behavior measures covary
Somatic Intervention
Alteration of a brain structure or function to see how behavior is altered
- IV: the brain structure or function that is being altered
- DV: the response that is measured, such as a behavior
Behavioral Intervention
Intervention of a behavior to see how brain structure or function is altered
- behavior is the independent variable
- body/brain changes are dependent variables
Correlation
Compares how much a body measures varies w/ a behavioral measure
- if one measure goes up while the other goes down, there is a negative correlation
- if both measures increase or decrease together, there is a positive correlation
- a correlation experiment may show an association between variables but cannot prove causality
Reductionism
Biopsych approaches the study of behavior from a reductionist approach
- the strategy of breaking a behavior down into increasingly smaller parts to understand it
- the approach is to understand behavior by examining different levels of analysis – from behavioral to molecular
The True “Final Frontier”
- Consciousness: the personal, private awareness of our emotions, intentions, thoughts and movements
- How is it possible that you are aware of the words in the textbook, the classroom we are occupying, the goals we have in life, or even that we are alive?
- While some scientists have found some empirical
evidence of consciousness as a property of the
brain, some questions will remain unanswered
because of the nature of the scientific question.
Animal Research Pros
The study of brain and behavior requires research on other species
Pros:
- can examine brain mechanisms at the cellular and molecular level using animal models
- enables scientists to set up rigorously controlled research designs
- can allow us to test the effects of drugs/treatments on a living body before they are tested on humans
- improve veterinary care for pets
- animals are biologically v similar to humans - mice share 97.5% of our DNA
- animals are susceptible to the same health problems as humans
- have shorter life cycles than humans
Animal Research Cons
- generlizability to humans?
- ethical concerns
–> institutional animal care and use committee (IACUC) - similar to IRB but for animals
–> IACUC is responsible for the oversight of animal care and use programs - a lot of oversight from government as well
What’s inside the brain?
- Blood vessels – gives the brain a red appearance
- Network of fibers (axons) – allows for communication to different parts of the brain/body
- Cells
–> Neurons – transmit an electrochemical signal
–> Glial – support cells
Visualizing Cells
Santiago Ramón y Cajal
- pioneer in neuroscience that first demonstrated that the cells in the
nervous system are separate and
that they did not merge into each
other as previously believed.
- Used a technique developed by Golgi that allowed some cells to be
visualized
Neuron Doctrine - Santiago Ramon y Cajal
- Discovery by Santiago Ramón y Cajal lead to the neuron doctrine
–> Nervous system is made up of individual cells that are structurally, metabolically and functionally independent.
–> Information is transmitted from neuron to neuron across tiny gaps (synapses – junction between two cells). - Neurons transmit an electrochemical signal
Neuron Anatomy
Four distinct regions:
- Dendrites
–> Input zone
- Soma (Cell body)
–> Integration zone - Axon
–> Conduction zone - Terminal button (Synaptic bouton)
–>Output zone - Focus will be to understand how neurons communicate
with other neurons
–> What are the proteins that allow for that to take
place - We will focus on a single
neuron, but know that there
are billions of neurons in our nervous system
Neuron Membrane
- Like all cells, neurons have an internal environment called the cytoplasm – (a semi-watery fluid that fills the inside of the cell ) that is separated from the external environment by
the neuronal membrane. Membrane is made of lipids (fat). Membrane has embedded
Dendrites
- Usually, many dendrites per cell
- Rough surface
(dendritic spines) - Branch near the cell body
- Referred to as Input Zone
- Bring electrical information to the cell body (graded
potentials) - No insulation (myelin sheath)
Cell body (Soma)
Referred to as Integration Zone
Important structures (organelles) are
found in the soma:
–> Nucleus – genetic material (DNA)
–> Endoplasmic reticulum – protein
synthesis
–> Ribosome – protein synthesis
–> Golgi Body – Packaging proteins
–> Lysosomes – degrades proteins
–> Mitochondria – provides stored energy in the form of adenosine
triphosphate (ATP)
Protein synthesis is an
important function in
SOMA
What are Proteins?
- Proteins (biggest):
Proteins are made up of
one or more polypeptide
that is twisted and folded
into a unique shape - Polypeptides (middle):
Polypeptides are a
string of amino acids
bonded together (less
than 50) - Amino Acids (smallest): Amino acids bond
together to form
polypeptides
Types of proteins
- transport
- channels
- antibody
- enzyme
- messenger
- signaling
- structural
Transport protein funct.
bind and carry molecules
Channel proteins funct.
allow the passages of ions across cells
Antibody protein funct.
bind to specific foreign particles
Enzyme protein funct.
carry out chemical reactions in cells
Messenger protein funct.
hormones or peptides that regulate biological processes
Signaling protein funct.
receptor proteins that recognize chemical signals
Structural protein funct.
provide structure and support of cells
Nucleus contains 23 pairs of chromosomes
A Gene is a segment of DNA that encodes for how to build proteins (i.e.,
the instructions on how to build the protein – provides the sequence of
amino acids)
* 23,000 genes
* 1.5% of genome
* 98.5% “Junk”
– No longer true
Protein Synthesis
- the instructions on how to assemble the amino acids together to form a protein are encoded within DNA
- 3 base code for an amino acid, but must be copied into mRNA
Transcription
- DNA is separated by an enzyme, which exposes a portion of a DNA strand.
- The strand is copied by RNA polymerase to synthesize mRNA (cannot transport DNA into cytoplasm – too large)
–> The copy is the same, except that Uracil (U) is used instead of Thymine (T)
Translation
- mRNA is transported to cytoplasm, where it interacts with Ribosomes (made up of rRNA)
- Ribosomes read mRNA strand to identify the amino acid that is needed.
–> 3 mRNA nucleotides or a “codon” encode for 1 of 20 amino acids
–> Amino acids are attached to tRNA, which have an “anticodon” which matches the codon on RNA
Essential function of the cell body
- Proteins are synthesized from amino acids that are linked together by ribosomes, which can then be shaped into complex structures.
- Proteins are essential for the cell to function– they allow the cell to carry out its functions.
Summary of Protein Synthesis
- DNA is transcribed to produce mRNA (transcription)
- mRNA is transported to cytoplasm
- Ribosome uses mRNA to assemble the chain of amino acids in order to form a protein (translation)
Axon
- Only found in neurons and is specialized to transfer information in the form of an electrical signal or action potential (Referred to as the conducting zone).
- Begins at axon hillock - membrane composition differs from soma membrane (i.e., specialized proteins are found here important for the action potential).
- Extends from less than a millimeter to a meter long and can have a fatty insulation around it called myelin sheath
- Axons branch out and are called axon collaterals
- Terminates at the terminal button (referred to as the output zone) – site where the axon makes contact with another neuron
- When an axons connects to another cells is referred to as a synapse
Cytoskeleton Proteins
- Internal scaffolding (structure)
- Not static – changeable , mobile, nonstationary
- Three “bones” of the neuron
–> Microtubules
–>Microfilaments
–> Neurofilaments
Axon Characteristics
- Take information away from the cell body
- smooth surface
- generally, 1 per cell
- can have myelin
- branch further from the cell body
Axoplasmic transport
- Microtubules allow for transportation of proteins across the neruon.
- Anterograde (soma to terminal)
–> Kinesin protein moves vesicle across the microtubule in an ATP dependent process.
–> Newly synthesized proteins - Retrograde (terminal to soma)
–> Dynactin protein transports back to soma across the microtubule in an ATP dependent process.
–>Way of communicating metabolic needs and waste material.
Dendrites characteristics
- Bring information to the cell body
- rough surface (dendritic spines)
- usually many per cell
- no myelin insulation
- branch near cell body
Synapse - Point of contact w another cell
The synapse consists of the axon terminal of a neuron (presynaptic neuron), a small gap (synaptic cleft), and the dendrite of a second neuron (postsynaptic neuron)
Synaptic Cleft - chemical signal
- Axons are not physically connected to other cells.
- The small space is called the synaptic cleft
- A chemical (referred to as the neurotransmitter) that is packaged in a vesicle at the presynaptic terminal button is released into the synaptic cleft to allow communication to the next cell
- Chemical travels to receptor proteins found on the postsynaptic membrane to transmit information (often triggering an electrical signal – graded potential)
Neuron Summary
- Dendrites (input zone) — structure which receives information from other neurons and transmits it towards the cell body (soma) via an electrical signal (graded potential)
- Soma (integration zone) — structure that processes the information and initiates an electrical signal (action potential).
- Axon or nerve fiber (conducting zone) — structure which transmits electrical signal (action potential) away from the cell body towards the terminal button. Sometimes insulated.
- Axon terminal or synaptic bouton (output zone) – The end of the axon which the neuron uses to transfers information to other cells via a chemical signal. The point of contact is called a synapse.
Where do transcription and translation take place?
transcription - (nucleus)
translation - soma/dendrites/axon
Visualizing Cells
- Nissl stain – organelles
- Golgi stain – cell body stain
- Immunocytochemistry –identify structure/proteins using antibodies
–> c-Fos protein – neuronal activity of cells - Tract tracing – tracing interconnections between neurons.
Neuronal types based on morphology
Neurons can be classified based on the number of neurites (axons and dendrites) they have.
- multipolar
- bipolar
- unipolar
ppt 2 slide 33
Brain by the numbers
Neurons
- There are about 100,000,000,000 neurons (100 billion) in our brain.
- There are 10 trillion synapses (connections between neurons)
- Neurons transmit information at 220 mph
- There are 100,000 miles of axons, enough to circle the earth four times
- The brain uses 20% of the body’s oxygen
- The brain does 10,000,000,000,000,000 calculations per second
Glial cells
- Glia refers to “glue” in Greek
- Glial cells are:
–> smaller than neurons (one-tenth the size)
–> more numerous than neurons (ten times) – 1 trillion.
–> not capable of an electrochemical signal (only neurons). - Glial cells provide support and nutrients to neurons.
- Several different types: astrocytes, microglia, oligodendrocyte, schwann cells
Astrocytes
- Star-shaped
- Most numerous of the glial cells
- Weave between neurons
- Provide physical support, transport nutrients, increase blood flow, help form synapses (neural plasticity)
Microglia
- Smallest glial cells
- Support neurons by removing debris, e.g., site of injury
Oligodendrocytes and Schwann cells
- Wrap around axons to insulate them with myelin – fatty insulation
- Oligodendrocytes (in brain and spinal cord) – myelinate multiple axons
- Schwann cells (in peripheral nervous system)– myelinate one axon
The Nervous System
Central Nervous System (CNS)
- Brain and Spinal Cord
- Encased within the skull and spinal column
Peripheral Nervous System (PNS)
- Made up of nerve tissue located outside of the brain and spinal cord
- Somatic nervous system
- Sensory and motor
- Autonomic nervous system
- Internal organs
Subdivisions of the Nervous Systems
ppt 2, slide 42
Functions of the Nervous System
Four main functions:
- Detect stimuli in the environment
- Recognize the significance of the environmental stimuli
- Make a decision based on the stimuli
- Execute a response
Simplified view
Functions are processed at different levels of the nervous system
Peripheral Nervous System (PNS)
- Detects environmental information inside and outside the body, which is then transmitted to the CNS
Central Nervous System (CNS)
- Recognizes and analyzes information from the PNS, makes decisions, and transmits decisions to glands, internal organs (e.g., heart), and muscles for execution
Peripheral Nervous System (PNS)
- Executes (or carries out) the decisions formed by the CNS
Sensory Processing by Afferent Nerves
- All animals have sensory organs containing receptor cells that sense some stimuli but not others.
- Sensory organs are very diverse, but all senses use the same type of electrical signal—action potentials.
- Sensory transduction—the conversion of energy from a stimulus into a change in membrane potential in a receptor cell to produce an action potential
Sensory transduction
Body sensations begin in the skin, where we have different types of skin mechanoreceptors.
ppt 2 slide 46
Neuron functions in Somatic Nervous System
ppt 2 slide 47
Autonomic NervousSystem Response
Sympathetic and Parasympathetic are typically antagonistic to each other (act in opposition to each other)
Sympathetic mobilizes energy so you can flee or fight.
Parasympathetic increases processes that replenishes energy (conserve)
ppt 2 slides 49,50,51,53
Electrical Potentials
- Resting Membrane Potential (RMP)
–> Resting does not mean inactive (still requires energy) - Graded Potentials
- Action Potentials
- Potential is a separation of charges across the membrane
- Measured in voltage (V) – the difference in electric potential between the inside and the outside of a neuron.
- The greater the voltage the more current (movement) you can see
