Post on 12-Jan-2016
Overview of the Day
Neuroscience - Part 2 The BrainThe Brain and BehaviorGenetics and Behavior
Why Has the Brain Been so Difficult to Study?
Most of it is enclosed in the skullIt just sits there and makes no obvious
movements [electrical/chemical, not mechanical, like the heart or skeleton]
Appears undifferentiated (all of it looks about the same
Ethics of studying human brainsDifferences between human an animal
brain function
How Can We Figure out How the Brain Works ?
Clinical observations of illnesses and damage to brain injuries in war or work damage to back of brain disrupted vision Phinous Gage, damage to frontal cortex resulted in DPC
Manipulating the brain
create brain injuries destroy parts of brain (lesions) and see what happens [ethical on
humans?--when done for other reasons: e.g., split brain, corpus callosum to ameliorate epilepsy]
stimulate it chemically or eclectically (Delgato and bulls)
Observe it
What about the Brain Would You Observe?
What it looks like (3D, X-ray) brain structure, shapes of different
types of peopleBrain activity
what parts of the brain are firing when people are engaged in different tasks
Brain Imaging Techniques:Technologies for Observing the Brain
CT (computed tomograph) scan X-rays of brain in 3d
PET (positron emission tomograph) scan Depicts activity of different brain areas by showing each
area's consumption of its chemical fuel (glucose). Active areas consume most fuel
MRI (magnetic resonance imaging) scan Detects signals from atoms in brain to give detailed
picture of brain's soft tissue
Major Parts of the Brain
Brainstem (oldest, evolved first)ThalamusCerebellumLimbic systemCerebral Cortex (evolved last)
Brainstem
Since it evolved first, what functions do you think it controls?
Medulla Heartbeat and breathing
Reticular formation arousal and sleeprelays information to other areas of the brain
Thalamus
Switchboard receives information from sensory
neurons and routes it to the higher brain regions that deal with seeing, hearing, tasting, and touching.
Cerebellum
Coordinates voluntary movement
Limbic System
Primarily deals with emotion Amygdala (aggression, fear)
Would psycho-surgery for violent criminals (modifying amygdala) be a good idea?
• Varied results: brain parts not completely isolated in terms of function• Easy to err when trying to localize brain functions
Hypothalamus (hunger, thirst, body temperature, and sexual behavior, pleasure center)
Hippocampus (memory)
Cerebral Cortex
Layer of cells on the top of the brain structure: body's control and information-processing center. that part of the brain most associated with our humanity (thought, planning, language, symbols)
Motor cortex (fine voluntary movements)Sensory cortex (this is where incoming
messages reach the cortex)Association areas (integrate
information) the more intelligent the animal, the greater
the amount of uncommitted association areas electrically probing these areas does not
trigger any specific response
Association areas
Frontal lobe judging, planning, personality, social
skills (Phinehas Gage-DPC)
Auditory and visual cortexes
Divided Brain
Right Half of the brain controls which side of the body? Pictures, faces, visual-spatial What percentage of gifted artists are-left
handedLeft Brain
language, numbers, analysisCorpus callosum (connects right and left
hemispheres of the brain)
Genetics and Behavior
Basic Units Genes: biochemical units of heredity
Chromosomes: egg and sperm cells each have 23 chromosomes: when they combine, the 46 chromosomes contain master plan for an individual's development
Genes and Human Development
Genes influence (G x E) Physical development: height, hair color,
skin color, ear lobe, curl tongue, bend thumb back
Behavioral tendencies: personality (anxiety, sensation seeking, shyness, physical and mental abilities
Individual differences (behavior genetics)Universal human characteristics
(evolutionary psychology)
Behavior Genetics
Hereditary influences on individual differences How we differ from one another (personality
and ability)
To what extent are we a product of our genes vs. our environment? Estimate heritability: the extent to which
differences among individuals is due to genes
Adoption studiesIdentical and fraternal twins, siblings
(natural and adopted) reared together and reared apart (separated
at birth)
Identical twins reared apart are more similar than natural or adopted siblings reared together in: intelligence and personality
Evolutionary Psychology
Why we are all the same: universal human tendencies just as our bodies were designed by natural
selection, so to natural selection designed they way people tend to think and behave--particularly with respect to behaviors and thinking that affects reproduction and survival
universal behavioral tendencies passed on through adaptive genes we all share
Study commonalties among people raised in different cultures preference for sweets, fats, salt fear of snakes and spiders women's preference for men who have status and wealth;
men’s preference for young, attractive females men in groups (coordinated action to achieve a goal,
dominance hierarchies); women in groups (independent, less competitive, more egalitarian)
strong bond between biological parents and their children (children with stepparents 40 more likely to be abused than children who are raised by both biological parents)
Summary
Studying the brainParts of the brainParts of the brain and behaviorDivided brainGenetics and behavior
behavior genetics evolutionary psychology