1. CHAPTER 2
Neuroscience
& Biological
Foundations

2. Lecture Overview
• Our Genetic Inheritance
• Neural Bases of Behavior
• Nervous System Organization
• A Tour Through the Brain

3. Our Genetic Inheritance
• Behavioral Genetics: study of the relative
effects of heredity & environment on behavior &
mental processes

4. Our Genetic Inheritance
• Evolutionary
Psychology:
studies how natural
selection &
adaptation help
explain behavior &
mental processes

5. Our Genetic Inheritance
• Neuroscience:
scientific study of the
biology of behavior &
mental processes

6. Our Genetic Inheritance:
Genes & DNA
• The nucleus of every cell
contains genes, which
carry the code for
hereditary transmission.
These genes are arranged
along chromosomes
(strands of paired DNA).

7. Our Genetic Inheritance
• Malnourished children
may not reach their
full genetic potential,
which demonstrates
how environmental
factors interact with
genetic factors.

9. Pause & Reflect:
Critical
Thinking
• Given that height
has one of the
highest heritability
estimates (around
90%), what other
factors might help
explain the height
differences in this
mother & daughter?

10. Neural Bases of Psychology
• Our nervous system
consists of neurons
(cells responsible for
receiving & conducting
electrical impulses from
the brain).

11. Neural Bases of Psychology:
The Structure of a Neuron

12. Neural Bases of Psychology:
Neural Communication
• Within a neuron, communication results from an
action potential (a neural impulse that carries
information along the axon of a neuron).

13. Neural Bases of Psychology:
Neural Communication (Continued)
• Between neurons,
communication occurs
through transmission of
neural information across
a synapse by
neurotransmitters
(chemicals released by
neurons that alter activity
in other neurons).

14. Neural Bases of Psychology:
Neural Communication (Continued)
• Receiving neurons
receive multiple
messages from other
neurons. These
multiple messages
then determine if an
action potential
occurs or not.

15. Neural Bases of Psychology:
Neural Communication (Continued)
• Note how the axon
terminals of sending
neurons almost
completely cover the
cell body of the
receiving neuron.

16. Pause &
Reflect:
Assessment
• What happens to excess neurotransmitters
or to those that do not “fit” into the adjacent
receptor sites? (Answer appears on the
next slide.)

17. Pause &
Reflect:
• The sending
Assessment
neuron normally
reabsorbs the
excess
neurotransmitters
(called “reuptake)
or they are broken
down by special
enzymes.

19. Neural Bases of Psychology
• Key neurotransmitters:
• Serotonin
• Acetylcholine (ACh)
• Dopamine (DA)
• Norepinephrine (NE)
• Epinephrine (adrenaline)
• GABA (gamma aminobutyric
acid)
• Endorphins

20. Neural Bases of Psychology
• Endocrine
System:
collection of
glands that
manufacture &
secrete
hormones into
the bloodstream

21. Neural Bases of Psychology
• Hormones: chemicals
manufactured by
endocrine glands &
circulated in the
bloodstream to
produce bodily
changes or to
maintain normal
bodily function.

22. Why Do We Need Two Communication
Systems--Neurotransmitters + Hormones?

23. Pause &
Reflect:
Assessment
1. _____ receive information from other neurons.
The _____ carries the neuron’s messages to
other body cells.
2. How does neural communication within
neurons differ from communication between
neurons?

24. Nervous System Organization
• Central Nervous System (CNS): brain &
spinal cord
• Peripheral Nervous System (PNS): all
nerves & neurons connecting CNS to
the rest of the body
– PNS is subdivided into the somatic &
autonomic nervous systems
– Autonomic nervous system
subdivided into sympathetic &
parasympathetic nervous systems

26. Central Nervous System:
Important Terms
• Neuroplasticity: brain’s lifelong ability
to reorganize & change its structure &
function throughout the life span
• Neurogenesis: division &
differentiation of nonneuronal cells to
produce neurons
• Stem Cells: precursor (immature)
cells with the potential to develop into
almost any type of cell

27. Pause & Reflect:
Critical
Thinking
• Understanding neurogenesis,
neuroplasticity, & stem cells helps make us
better informed consumers of scientific
research & more knowledgeable
participants in political debates. Can you
explain why?

28. Nervous System Organization:
Central Nervous System (CNS)
• Brain
• Spinal Cord:
transmits
information into &
out of the brain

30. Nervous System Organization:
Central Nervous System (CNS)
• The spinal cord is
also responsible
for involuntary,
automatic
behaviors called
reflexes.

31. Nervous System Organization:
Peripheral Nervous System (PNS)
• PNS connects CNS to the rest of the body;
subdivided into:
– Somatic Nervous System (SNS): connects
sensory receptors & controls skeletal muscles
– Autonomic Nervous System (ANS): controls
involuntary bodily functions; subdivided into:
»Sympathetic Nervous System (arouses)
»Parasympathetic Nervous System (calms)

33. Nervous System Organization
 Anatomy & functions of the sympathetic (arouses)
& parasympathetic (calms) nervous systems

34. Pause &
Reflect:
1. You touch a hot stove & then
Assessment pull away. This
immediately & reflexively
action was controlled by _____.
2. After being startled by the sight & sound
of a fierce dog rushing toward you, it is
most likely that your _____ is dominant.

35. A Tour Through the Brain
• Lower-level brain
structures:
– Hindbrain
– Midbrain
– Parts of the
Forebrain

37. A Tour Through The Brain:
Hindbrain
• Key structures & functions of the hindbrain:
– Medulla: life survival functions
– Pons: respiration, movement, waking,
sleeping, & dreaming
– Cerebellum: coordination of fine muscle
movement, balance, & some aspects of
perception & cognition

38. A Tour Through The Brain
(Continued)
• Midbrain: collection of brain structures in the
middle of the brain; coordinates movement
patterns, sleep, & arousal
• Reticular Formation: runs through the
hindbrain, midbrain, & brainstem; filters
incoming information & controls arousal

39. A Tour Through The Brain
(Continued)
• Forebrain: collection of upper-level brain
structures, including the thalamus, hypothalamus,
limbic system, & cerebral cortex
– Thalamus: relays sensory messages to the
cerebral cortex
– Hypothalamus: responsible for drives,
hormones, & regulating the body’s internal
environment

40. A Tour Through The Brain
(Continued)
• Limbic System:
interconnected group
of forebrain
structures involved
with emotions,
drives, & memory

41. Structures of the Forebrain

42. Pause &
Reflect:
1. What are the three key structures of the
Assessment
hindbrain?
2. The _____ includes the thalamus,
hypothalamus, & limbic system.

43. Pause & Reflect:
Assessment

44. A Tour Through The Brain:
Cerebral Cortex
• Cerebral Cortex: thin
surface layer on the
left & right cerebral
hemispheres;
regulates most
complex behavior,
including sensations,
motor control, & higher
mental processes

45. A Tour Through The Brain:
Lobes of the Cerebral Cortex

46. A Tour Through The Brain:
Lobes of the Cerebral Cortex
•Frontal Lobes: receive &
coordinate messages
from other lobes;
responsible for motor
control, speech
production, & higher
functions, such as
thinking, personality,
emotion, & memory

47. Pause & Reflect:
Critical
Thinking
• Do you recall from Chapter 1
Phineas Gage’ s mining
accident, which sent a 13-
pound tamping iron through
his frontal lobes? How did
this affect his short- & long-
term behavior & mental
processes?

48. A Tour Through The Brain:
Lobes of the Cerebral Cortex (Cont.)
• Parietal Lobes: located at the
top of the brain directly behind
the frontal lobes; responsible for
interpreting bodily sensations
• Temporal Lobes: located on
each side of the brain above the
ears; responsible for audition,
language comprehension,
memory, & some emotional
control

49. A Tour Through The Brain:
Lobes of the Cerebral Cortex (Cont.)
• Occipital Lobes:
located at the back
of the brain;
responsible for
vision & visual
perception

50. A Tour Through The Brain:
Motor Cortex & Somatosensory Cortex

51. Pause & Reflect:
Critical
Thinking
• Why are the hands
& face on this
drawing so large?
What do they
represent?

52. A Tour Through The Brain:
Split-Brain Research
• Severing the
corpus callosum,
for medical
reasons, also
provides
information on
the role &
functions of the
left & right
hemispheres.

53. A Tour Through The Brain:
Split-Brain Research

54. A Tour Through The Brain:
Lateralization
• The left & right
hemispheres
specialize in
particular (but often
overlapping)
operations.

55. Pause &
Reflect:
1. What are the major functions of the four
Assessment
lobes of the brain?
2. The _____ hemisphere is primarily
responsible for language, & it controls
the right side of the body.

56. End of CHAPTER 2
Neuroscience
& Biological
Foundations