What are neurons?
Brain cells that provide the foundation for the nervous system; 100 billion neurons in the human brain
Dendrites
Branches that extend from the top of the neuron; they receive information from other neurons
Cell Body/Soma
Contains the nucleus, which holds genetic information and contains energy and necessary resources
Axon
Main source of output in the neuron; carries signal
Myelin Sheath
A fatty, insulating substance that covers the axon and allows for messages to travel faster down the axon
Terminal Buttons
At the end of the neuron; sends messages out to other neurons
Synapse (synaptic gap and synaptic vesicles)
The space between two neurons; the message of one neuron gets picked up by another in this space
Neurotransmitter
Chemical message
Types of cells?
Neurons and Glial Cells
Neuron Types
Sensory, Motor, and Interneurons
Sensory Neurons
Unipolar; afferent; carries messages away to the central nervous system; helps us receives information form the world
Motor Neurons
Multipolar; efferent; carries messages from the central nervous system to the voluntary muscles and glands; helps us to initiate movement and interact in the world
Interneurons
Bipolar; connect the sensory and motor neurons
Glial Cells (and types)
Cells in the brain with several functions based on type; oligodendroglia, microglia, and astrocytes
Oligodendroglia
Forms the myelin sheath
Microglia and Astrocytes
Digest debris of dead neurons, carries nutrition to neurons and regulate ionic composition
Resting State (resting membrane potential)
Stable negative charge; the voltage of the neuron (~70mV) while it is at rest; negative charge before firing or when messages are sent
Action Potential (change in electrical charge)
Causes the neuron to fire; when messages are sent; current goes down axon
1) Threshold of excitation: specific membrane potential that must be reached for an action potential to occur, around ~50mV
2) Change in membrane potential: due to unequal distribut
Absolute Refractory Period
The time immediately after a neuron has fired in which it cannot fire again
All-or-none law
The neuron either fires or it doesn't
Ex: a gun
Communication within neurons
Electrical reaction
Communication between neurons
Chemical reaction; neurotransmitters
1) At synapse action potential causes the release of neurotransmitters; chemical messages transfer from one neuron to another after the action potential
2) Neurotransmitters cross the synaptic gap
3) Lock and key type
Types of messages carried by neurotransmitters?
PSP, EPSP, IPSP, and Reuptake
Postsynaptic Potential (PSP)
Voltage change at receptor on a postsynaptic cell membrane; change in voltage
Excitatory (EPSP)
Positive voltage shift and increase chance that PSP neuron will fire; depolarizes neuron, making it more positively charged
Inhibitory (IPSP)
Negative voltage shift that decreases the chance that PSP neuron will fire; hyper-polarizes the neuron making it more negatively charged
Reuptake
When the neurotransmitter doesn't bind to any receptors, it is broken down and deactivated or taken back into presynaptic terminal button; SSRI's allow neurotransmitters to remain active for longer periods of times
Acetylcholine (Ach)
Activates motor neurons that control skeletal muscles (peripheral nervous system); contributes to regulation of attention, arousal and memory: most common; lack of Ach - muscle paralysis
Glutamate (GLU)
Main excitatory neurotransmitter in the brain: learning and memory
Gamma-amino butyric acid (GABA)
Main inhibitory neurotransmitter in the brain; anxiety disorders; epilepsy
Dopamine (DA)
Control of voluntary movement; important in reward circuits; too much - Schizophrenia; too little - Parkinson's disease
Serotonin (SHT)
Emotion regulation; depression; aggression; SSRI's keep levels of serotonin active for longer
Endorphins
pain: analgesia; reward
Major Divisions of the Nervous System
Peripheral nervous system (PNS); Central Nervous System (CNS): brain and spinal cord
Peripheral Nervous System
1) Somatic division: necessary for voluntary actions (raising your hand); cranial nerves (12); spinal nerves (31)
2) Autonomic divison: important for involuntary actions (heart, lungs); sympathetic: energizes and causes action, "fight or flight" and "go";
Central Nervous System
1) Forebrain: thalamus, cerebrum (cortex and limbic system)
2) Midbrain
3) Hindbrain: pons, cerebellum, and medulla
4) Spinal cord: transmits messages between he brain and rest of the body (reflexes)
Electroencephalogram (EEG)
Measures electrical brain wave activity of many neurons in the brain; electrodes utilize when subject is performing a task
Functional Magnetic Resonance Imaging (fMRI)
Measures activity by studying changes in oxygen levels in blood; gauge normal functioning; takes rapid succession pictures
Position Emission Tomography (PET)
Studies brain activity via an injected radioactive substance; can deduce place in brain where activity is occurring via the colors from the substance
Transcranial Magnetic Stimulation (TMS)
Magnetic pulse applied to head and induce an electrical current in the brain; allows the study of when events in the brain occur; temporal resolution
Medulla
Important for breathing and heart beating
Pons
Transmits motor information
Cerebellum
The "small" brain; contains the highest number of neurons of any brain structure; important for balance
Reticular formation
Passes through the midbrain and into the forebrain; activates other parts of the brain; producing bodily arousal; hearing a fire alarm
Thalamus
The relay station for information about the senses
Hypothalamus
Focus on homeostasis; hunger, thirst, temperature control
Amygdala
Emotions and aggression
Hippocampus
Memory and learning emotional memories better remembered; if damaged, no memory formation
Cerebral Cortex
The largest, most visible part of the brain outer surfaces of the brain (two hemispheres); characteristic gray color and groves appearance
Frontal Lobes
In the front of the cerebrum
Functions: motor planning and output, language, judgement, memory search, decision making
Parietal Lobes
In the top, rear part of the cerebrum
Functions: visual attention, bodily sensations, spatial location, and integrating the senses
Ex: falling and feeling pain
Temporal Lobes
In the front, bottom of the cerebrum
Functions: vision, language, and auditory processing, memory, and integrating auditory and visual information
Occipital Lobes
At the bottom and back of the cerebrum
Functions: Visual processing
Ex: distinguishing between colors
Motor area of cortex
Responsible for voluntary movement; houses under the frontal lobe; giving someone a high
Sensory area of the cortex
Somatosensory area: responsible for bodily sensations house under the parietal lobe (touch and pressure)
Association of the cortex
Executive functions that are not specifically involved in sensation or motor processes
1) Broca's Aphasia (Frontal Lobe): problems speaking
2) Wernicke's Aphasia (Temporal Lobe): problems understanding speech/writing
Neuroplasticity
The brain continually reorganizing itself; ability of neurons to change in structure/function and to change location to help damaged areas
Neurogenesis
New neurons are created in certain areas of the brain throughout life
Hemispheric specialization
Specific functions reside in only one hemisphere; but both side work together; corpus callosum links them together
1) Left: language processing and logical analytical thought
2) Right: spatial relationships, abstract thought, creativity
Split-brain operation
Corpus callosum surgically severed (2 hemispheres aren't connected); as though person has two separate brain now
What we learned: each side and the brain and its functions can be studies less competition between the two hemispheres (can search for informa
What is psychology?
The study of behavior and the physiological and mental processes that go along with it; the scientific study of the human mind and its functions, mostly those affecting behavior
Where do most psychologists work?
Most work in academic settings or in private practice
Psychologist vs. psychiatrist
Not the same! Psychiatrists can prescribe medicine and must go to medical school, while psychologist cannot prescribe medicine, (both diagnose and treat mental disorders)
Roots of psychology are in...
Philosophy and physiology
Empiricism?
All knowledge comes from experience
John Locke
Famous empiricist (mission was to get rid of rationalism)
Hermann Helmholtz
Studied neural impulse and physiology of hearing and vision
Gustav Fechner
Studied psychophysics (relationship between physical stimuli and the human perception of stimuli)
Wilhelm Wundt
Credited with the formal beginning of psychology; established experimental psych as field, developed first psych lab in Germany; introspection
Introspection
Training the mind to focus deeper internal information
Structuralism
Sought to describe the elements of conscious experiment; Bradford Titchener- student of Wundt's, brought brand of experimental psych to America and founded Structuralism
Functionalism
Focused on mental processes and behavior, looked at how something happened (opposite to Structuralism)
William James
Functionalism Impact: Wrote Principle of Psych (1890); stream of consciousness - conscious thought as ever changing, continuous, personal thought
Stanley Hall
Functionalism Impact: Founded APA, made first psych lab in America, made first psych journal in American; studied adaption and development
James Cattell
Functionalism Impact: studied individual difference and the difference in individual intelligence
Gestalt Psychology
Focus on the whole experience; the whole is greater than a sum of its part; considered a precusros to cognitive psychology
Behaviorism
Focused on observable behavior and how to control it; no explanation of mental processes, opposes cognitive psych; created due to insufficiency of structuralism and functionalism
1) Ivan Pavlov - classical conditioning
2) John Watson - little Albert
3) B.
Cognitive Psychology
Behaviorism couldn't fully explain human behavior; focuses on mind and mental processes
- mind = "the black box"
1) F.C. Bartlett - use past frameworks/experience to understand new experiences
2) Jerome Bruner - different ways to study sensation and perce
Fact vs. Opinion
Fact is associated with scientific method while an opinion is associated with personal experience
Mental testing
A test for identifying children that need education support nature vs. nuture; highly debated
Scientific method
Approach to systematically acquire knowledge and understanding about behavior and other phenomena of interest
Systematic observation
Observing the natural world to gain knowledge
Theory
Broad explanation and predictions concerning phenomena of interest
Hypothesis
A testable prediction
Operational definition
Translation of a hypothesis into specific, testable procedures that can be measures/observes
Replication
Important to ensure accurate results
Ethics
Ways to ensure that participants are protected and the integrity of the experiment is safe
1) Benefits should out way risk
2) Confidentiality: secure from public
3) Right to privacy
4) Informed consent: written documentation about experiment presented fir
Archival Research
Past data; looking through newspaper, records, etc.
Case study
Looking at one or a few cases to apply to a whole population
Disadvantage: lack of generalizability
Naturalistic Observation/Ethnography
Watching an environment without manipulation anything
Survey Research
Polls, questionnaires
Correlational Research
The passive observation and measure of phenomenon; variables: behaviors, events, characteristic that can change/vary on some level; correlation coefficient (0-1) - positive (as one variable increase so does the other) and negative (as one variable increas
Does correlation cause causation?
No, there could be a third variable that is affecting the relationship; does show directionality
Experimental Research
Different from correlational research; investigation of relationship between at least two variables; IV and DV
1) Operational Definitions
2) Experimental Manipulations: manipulate variable to learn about another
3) Experimental and control groups: experim
Researchers Expectations
When researchers expect to find certain results' the study may be influenced
Double-blind procedure
Neither the researcher nor the participant knows about the group memberships
Participant Expectations
When participants know their group, expectations/membership, influences their behavior (or try to do what experimenter wants them to do/say)
Placebo
Participants do not know their group memberships, deception - then debrief
Quasi-Experimental designs
A design that does not require random assignment; rely on previous, existing group membership
Longitudinal studies
A design that follows the same people over time (can last years)