Download Neuroscience

Psychology as Science
• Psychology is the study of human thought and
behavior, and the application of the gained
knowledge.
• Areas of Study:
• Basic Research: Tries to acquire knowledge. Includes
neuroscience, developmental, social, cognitive, and
personality psychology.
• Applied Psychology: Uses acquired knowledge. Includes
clinical and industrial/organizational psychology.
The scientific method
•Construct a theory: an explanation of a
phenomenon using an integrated set of
principles that organizes observations and
predicts behavior.
•A good theory should produce testable
predictions called hypotheses.
Hypotheses
• Hypotheses are predictions of particular outcomes.
• Always hypothesize a difference.
• Hypotheses must be testable.
• You should include directionality in the hypothesis.
• Viewing more TV will increase anxiety.
• A hypothesis is usually formulated after careful
observation.
To test a hypothesis, we conduct an experiment.
Research Methods
• Experiments: Researchers directly manipulate one variable
(Independent Variable) and measure the resulting effects on
another variable (Dependent Variable) while keeping all other
variables constant.
• Confounding Variables:
• Placebo effects- changes in state due to receiving a
treatment when the treatment itself has no biological
effects.
• Subject variables- variables that human subjects bring in
with them, such as age, sex, occupation, etc.
• Random assignment: participants are randomly assigned to a
treatment condition, so all participants have an equal chance
of being assigned to every condition. Solves subject variable
confounds.
Research Methods Cont.
• Correlational Research: Indicates the extent to which two
variables vary together. (Use scatterplots to see trends)
• Does NOT imply causation.
• These methods are used when experiments are either impractical or
ethically impossible.
• If you know one variable you can then predict the other.
• Positive Correlation: as one variable increases so does the other.
• Negative Correlation: as one variable increases, the other variable decreases.
Correlation coefficient (r):
Ranges from -1 to +1.
0 = zero correlation
Behavioral Neuroscience
Collect
Transform
Transmit
Layout of nervous system
Nervous system
Peripheral
Autonomic (selfregulated action
of internal organs
and glands)
Sympathetic
(arousal)
Somatic
(voluntary
movement of
skeletal muscles)
Parasympathetic
(relaxation)
Central
Brain (further
divisions coming!)
Spinal Cord
Neuron structure
Signal:
Action
Potential
Neuron Resting State
• Neuronal membrane is fatty and won’t let ions in. Ions can
only go through special gates and pumps.
• Lots of potassium (K+) inside the cell
• Lots of sodium (Na+) and chloride (Cl-) outside the cell
• Overall, inside of the cell is more negative, outside is more
positive.
• Gates and pumps work to keep the right amounts of ions
inside/outside the cell.
Action Potential
• Depolarization happens when
Na+ rushes into the neuron,
making it more positive.
• If this brings the voltage to the
threshold potential, an action
potential happens.
• Runaway cascade of Na+ entry.
• Cell repolarizes as K+ reactively
rushes out of the cell.
• Pumps and gates work to
reachieve resting state.
• Cell cannot fire during this
period – refractory period.
Neurotransmitters
• Neurons “talk” to each other using chemical
neurotransmitters.
• Fast acting:
• Glutamate (excitatory), GABA (inhibitory), &
Acetylcholine (movement)
• Slow acting:
• Dopamine (pleasure), Serotonin (mood), Substance
P (runners high)
Synaptic Events
1) Action potential reaches axon terminal.
2) Vesicles containing neurotransmitter release their
contents into the synaptic cleft.
3) Neurotransmitters bind with receptors on receiving
neuron, causing change in its potential.
4) Neurotransmitters release from receptors and then
1) Are destroyed by enzymes in the synaptic cleft
2) Or are reabsorbed back into the presynaptic axon terminal
(“reuptake”)
Major Structures
• Hindbrain:
• Medulla: respiration/BP, vomiting
• Cerebellum & Pons: coordinated movement
• Midbrain:
• Reticular Formation: arousal, alertness
• Inferior Colliculus: auditory localization
• Superior Colliculus: visual localization
• Forebrain:
• Hypothalamus: homeostasis
• Thalamus: relay station
• Limbic System: emotion & memory
• Amygdala: emotion
• Nucleus Accumbens: rewards
• Hippocampus: memory
• Cortex: higher order cognition
Pp. 64-68
What to remember
when making an
educated guess:
1. Older & lower brain
structures are for more
survival based
functions like
breathing, seeing and
moving.
2. Higher/newer
structures are for more
advanced functions
such as cognition and
language.
The Four Lobes of the Cortex
The Brain
Cortex & Specialization of Function
Brain Plasticity
• Describes the brain’s capacity for remodeling itself,
brain is amazingly plastic in early life
• Case of hydrocephalus
• Limits of Plasticity
• Fetal Alcohol Syndrome disrupts genetically
preprogrammed neuron birth and migration
Human Development
Domains of Change During
Development
•Biological: physical development.
•Cognitive: development of thought and mind.
•Social: development of patterns of interaction
with others.
•Moral/Ethical: development of a sense of right
and wrong and personal responsibility.
Cognitive Development
• Piaget hypothesized the following:
• Thinking and reasoning develop in stages
• Each stage is genetically preprogrammed, so the environment
can only change the speed that we pass through the stages.
• Schema: framework for understanding the world around
us.
• Assimilation: fitting new information into an existing
schema.
• Accommodation: modifying or creating a new schema to
represent new information.
Piaget’s Four Stage Theory
• Sensorimotor: Child understands through sensing and
acting. Ages 0-2
• Limitations: Cannot distinguish past & future, no object
permanence, cannot think symbolically
• Milestone: object permanence, stranger anxiety
• Preoperational: Ages 2-6
• Limitations: Poor reasoning (conservation tasks)
• Milestone: symbolic thought, language
• Concrete Operational: Ages 6-11
• Limitations: Poor reasoning about the abstract
• Milestone: logical reasoning for observable things (can do
conservation tasks)
• Formal Operational: Ages 11-adulthood
• Milestone: logical reasoning for unobservable or abstract
events/things (calculus)
Social
Development:
Attachment
• Harlow’s Monkeys
• Preferred the “warm fuzzy” surrogate mother to the food
providing mother
• As adults, monkeys showed erratic behavior in groups. They
were also poor mothers at first, but with time, learned to
engage in responsive parenting.
• Effects of Daycare
• Attachment isn’t affected as long as you don’t have an
insensitive, unresponsive mother and low quality daycare
(NIH, 1996)