Presentation is loading. Please wait.

Presentation is loading. Please wait.

© 2014 John Wiley & Sons, Inc. All rights reserved.

Similar presentations


Presentation on theme: "© 2014 John Wiley & Sons, Inc. All rights reserved."— Presentation transcript:

1 © 2014 John Wiley & Sons, Inc. All rights reserved.
Chapter two Neuroscience and Biological Foundations Our Genetic Inheritance Neural Bases of Behavior Nervous System Organization A Tour Through the Brain © 2014 John Wiley & Sons, Inc. All rights reserved.

2 © 2014 John Wiley & Sons, Inc. All rights reserved.
Things You’ll Learn in Chapter 2 Can our genes influence whom we vote for in presidential elections? Q1 Why can spending the first few months of life in an orphanage lead to long-term problems in cognitive functioning? Q2 Q3 How can a chemical in the brain lead rats to binge-eat M&Ms? Q4 How can stem cell injections lead to restored vision and improved recovery from strokes? Q5 Why are former NFL athletes at increased risk of depression, dementia, and suicide? © 2014 John Wiley & Sons, Inc. All rights reserved.

3 Our genetic inheritance
© 2014 John Wiley & Sons, Inc. All rights reserved.

4 © 2014 John Wiley & Sons, Inc. All rights reserved.
Behavior Genetics The study of how heredity and environment affect us Evolutionary psychology = the application of principles of evolution to explain behavior and mental processes Genes control the transmission of traits Modern research shows most human characteristics are polygenic (controlled by multiple genes, not merely one dominant or two recessive genes) Most serious genetic disorders are not transmitted by dominant genes. Why? © 2014 John Wiley & Sons, Inc. All rights reserved.

5 © 2014 John Wiley & Sons, Inc. All rights reserved.
Most people understand that genes affect our health, such as potential for heart disease, diabetes, and cancer Genes also affect our personality traits, behavioral habits, sexual orientation, and psychological disorders Q1 Can our genes influence whom we vote for in presidential elections? Genes can even influence which political party we side with, and our views on death penalty, unemployment, and abortion (Hatemi & McDermott, 2012) © 2014 John Wiley & Sons, Inc. All rights reserved.

6 Gene-Environment Interaction
Environmental factors – both physical and psychological – also influence our characteristics Malnourished children may not reach their full potential genetic height or maximum intelligence © 2014 John Wiley & Sons, Inc. All rights reserved.

7 © 2014 John Wiley & Sons, Inc. All rights reserved.
Genes vs. Environment Identical twins share all their genes, fraternal twins share about half of their genes (just like non-twin siblings) Twins raised together by birth parents share the same environment Identical twins should be more alike than fraternal twins (such as in intelligence) Research on adoptive children can trace characteristics to birth parents vs. adoptive parents Research shows many psychological traits (and disorders) run in biological families How can psychologists separate genetic causes from environmental causes? © 2014 John Wiley & Sons, Inc. All rights reserved.

8 © 2014 John Wiley & Sons, Inc. All rights reserved.
Heritability Heritability = the percentage of variation in a population attributable to heredity If no genetic influence, heritability would be 0% If no environmental influence, heritability would be 100% Heritability does NOT apply to INDIVIDUALS Heritability does not trump environment 1. Heritability does NOT apply to INDIVIDUALS. Ex: height is 90% heritable, but that doesn’t mean that 90% of YOUR height is due to genes. Instead, 90% of the differences in people’s height can be explained by genetics. 2. Heritability does not trump environment. Ex: if you inherit a gene known to increase your changes of developing emphysema from smoking, this doesn’t guarantee you’ll develop emphysema … especially if you never smoke! © 2014 John Wiley & Sons, Inc. All rights reserved.

9 Evolutionary Psychology
Many behaviors emerged and still exist because they helped our ancestors survive Natural selection = particular genetic trait gives an organism a reproductive advantage “Reproduction of the fittest,” not “survival of the fittest” © 2014 John Wiley & Sons, Inc. All rights reserved.

10 Neural bases of behavior
© 2014 John Wiley & Sons, Inc. All rights reserved.

11 © 2014 John Wiley & Sons, Inc. All rights reserved.
The Basics Building blocks of brain and nervous system: Neurons = responsible for receiving, processing, and transmitting electrochemical information Glial cells = provide structure, nutrition and other support to neurons © 2014 John Wiley & Sons, Inc. All rights reserved.

12 © 2014 John Wiley & Sons, Inc. All rights reserved.
Parts of a Neuron Dendrites = branching fibers that receive impulses from other neurons and send them to the cell body Cell body = AKA soma, contains cell nucleus Axon = long, tube-like structure that sends impulses away from cell body to other neurons (or to muscles, glands) © 2014 John Wiley & Sons, Inc. All rights reserved.

13 © 2014 John Wiley & Sons, Inc. All rights reserved.
Action Potential © 2014 John Wiley & Sons, Inc. All rights reserved.

14 © 2014 John Wiley & Sons, Inc. All rights reserved.
Action Potential Sequence of depolarization and repolarization moves the action potential from the cell body to the axon terminal buttons like the “wave” © 2014 John Wiley & Sons, Inc. All rights reserved.

15 © 2014 John Wiley & Sons, Inc. All rights reserved.
Speed of Thought Electricity moves 36 million meters/second Nerve impulses move 10 meters/second Nerve impulses move 10x faster through axons with myelin sheath Why can spending the first few months of life in an orphanage lead to long-term problems in cognitive functioning? Q2 Social isolation during early weeks/months of life (as for babies in orphanage) prevents proper growth of myelin, leading to long-term cognitive impairment © 2014 John Wiley & Sons, Inc. All rights reserved.

16 Communication Between
Communication WITHIN neuron is electrical, but communication BETWEEN neurons is chemical Sending neuron gets close to receiving neuron at synaptic gap, where neurotransmitters (chemicals) cross the gap to deliver the message © 2014 John Wiley & Sons, Inc. All rights reserved.

17 How Neurotransmitters Work
Reuptake © 2014 John Wiley & Sons, Inc. All rights reserved.

18 © 2014 John Wiley & Sons, Inc. All rights reserved.
Lock and Key © 2014 John Wiley & Sons, Inc. All rights reserved.

19 Common Neurotransmitters
© 2014 John Wiley & Sons, Inc. All rights reserved.

20 © 2014 John Wiley & Sons, Inc. All rights reserved.
Endorphins Common neurotransmitter elevate mood, reduce pain Opium-based drugs mimic the body’s natural endorphins How can a chemical in the brain lead rats to binge-eat M&Ms? Q3 Endorphins affect memory, learning, appetite, and sexual activity. Rats injected with endorphins ate 5% of their body weight in M&Ms! © 2014 John Wiley & Sons, Inc. All rights reserved.

21 Hormones & the Endocrine System
Endocrine system = network of glands located throughout the body that secretes hormones into the bloodstream Neurons send messages to certain receptors; hormone messages are carried by the blood to any cell that will listen Regulates and maintains long-term body processes, such as growth, sexual characteristics, digestion, and elimination Controls response to emergencies: adrenal glands release cortisol, epinephrine, and norepinephrine © 2014 John Wiley & Sons, Inc. All rights reserved.

22 Nervous system organization
© 2014 John Wiley & Sons, Inc. All rights reserved.

23 © 2014 John Wiley & Sons, Inc. All rights reserved.

24 Central Nervous System (CNS)
CNS is powerful, but fragile Neuroplasticity = brain can reorganize its functional structure due to usage and experience Q4 How can stem cell injections lead to restored vision and improved recovery from strokes? Neurogenesis = lost cells can be replaced by neural stem cells (rare immature cells that can migrate and grow into any type of cell). No cell transplant for spinal cord injuries in humans, but animal research shows stem cell treatment leads to improvement in paralyzed limbs © 2014 John Wiley & Sons, Inc. All rights reserved.

25 Spinal Cord Relays AND initiates vital information to other parts of the body Reflexes = automatic behavior in response to stimuli Allows immediate action without delay of routing through brain What is the evolutionary benefit of the reflex arc? © 2014 John Wiley & Sons, Inc. All rights reserved.

26 © 2014 John Wiley & Sons, Inc. All rights reserved.
Newborn Reflexes A Rooting reflex – Lightly stroke the cheek and watch how the infant automatically (reflexively) turns toward the stimulation and attempts to suck B Grasping Reflex – Place your finger or an object in the infant’s palm and note the automatic grasp Engage Your Students! What might happen if infants lacked these reflexes? Why do most infant reflexes disappear within the first year? C Babinski Reflex – Lightly stroke the sole of the foot, and the big toe will move toward the top, while the other toes fan out. © 2014 John Wiley & Sons, Inc. All rights reserved.

27 Peripheral Nervous System (PNS)
The part of the nervous system outside the brain and spinal cord Carries information to and from the CNS Links brain and spinal cord to body’s sense receptors, muscles and glands Somatic nervous system (SNS): carries sensory information to the brain and instructions back to skeletal muscles Autonomic nervous system (ANS): responsible for involuntary tasks like heart rate, digestion, and breathing © 2014 John Wiley & Sons, Inc. All rights reserved.

28 Autonomic Nervous System
Sympathetic division: mobilizes energy to respond to stressor (fight or flight) Parasympathetic division: calms body to conserve energy, returns body to normal functioning after stress © 2014 John Wiley & Sons, Inc. All rights reserved.

29 A tour through the brain
© 2014 John Wiley & Sons, Inc. All rights reserved.

30 Biological Tools for Research
© 2014 John Wiley & Sons, Inc. All rights reserved.

31 Biological Tools for Research (cont.)
© 2014 John Wiley & Sons, Inc. All rights reserved.

32 © 2014 John Wiley & Sons, Inc. All rights reserved.
Forebrain Limbic System – The interconnected group of forebrain structures involved with emotions, drives, and memory, as well as major physiological functions Cerebral Cortex– The thin surface layer that regulates most complex behavior (i.e. sensations, motor control). © 2014 John Wiley & Sons, Inc. All rights reserved.

33 © 2014 John Wiley & Sons, Inc. All rights reserved.
Limbic System Hippocampus– Seahorse shaped part of the limbic system involved in forming and retrieving memories Amygdala– Part of the limbic system that controls emotions, like aggression and fear. © 2014 John Wiley & Sons, Inc. All rights reserved.

34 © 2014 John Wiley & Sons, Inc. All rights reserved.
Cerebral cortex = surface layer of the brain Responsible for most complex behaviors and higher mental processes Damage to cerebral cortex linked to substance abuse, dementia, and suicide Q5 Why are former NFL athletes at increased risk of depression, dementia, and suicide? Trauma is particularly common in contact sports, like football, ice hockey, boxing, and soccer © 2014 John Wiley & Sons, Inc. All rights reserved.

35 © 2014 John Wiley & Sons, Inc. All rights reserved.
Lobes © 2014 John Wiley & Sons, Inc. All rights reserved.

36 © 2014 John Wiley & Sons, Inc. All rights reserved.
In 1848, 25-year-old railroad worker Phineas Gage had a metal rod accidentally blown through the front of his face, destroying much of his brain’s frontal lobe Experienced drastic personality changes; became impatient and lacked concern for coworkers He eventually obtained a job driving a stagecoach, which required high motor, cognitive, and interpersonal skills Engage Your Students! Based on the information provided, did the researchers use descriptive, correlational, and/or experimental research? If descriptive, is it naturalistic observation, survey/interview, case study or archival? If correlation, is this a positive, negative, or zero correlation? If experimental, label the IV, DV, experimental groups and control group What does modern research about neuroplasticity tell us about Gage’s possible recovery? © 2014 John Wiley & Sons, Inc. All rights reserved.

37 © 2014 John Wiley & Sons, Inc. All rights reserved.
Two Brains in One? Each hemisphere controls the opposite site of the body Corpus callosum = thick band of nerves, connects the two hemispheres Although each side of the brain might have a specialty (like Broca’s area for speech in the left hemisphere), when specific regions of the brain are injured or destroyed their functions can be assumed by neighboring region – or even opposite hemisphere © 2014 John Wiley & Sons, Inc. All rights reserved.

38 © 2014 John Wiley & Sons, Inc. All rights reserved.
Popular myth says left brain is analytical and right brain manages creativity Research shows both hemispheres work together in an integrated manner, like teammates playing soccer; each area might have specialties, but everyone knows what the other is doing and can help when needed © 2014 John Wiley & Sons, Inc. All rights reserved.

39 © 2014 John Wiley & Sons, Inc. All rights reserved.


Download ppt "© 2014 John Wiley & Sons, Inc. All rights reserved."

Similar presentations


Ads by Google