1. Neuroscience &
Psychology

2. Objectives
 Gain a general understanding of the nervous system
 Gain knowledge of the structure and function of the neuron
 Navigate your way around the major brain areas and
understand their function

3. Nervous System Hierarchy

4. Central nervous system
 Brain
 ~2% of body weight, uses ~20% of resources
 Composed of bunches of neurons, which form nerves
 Spinal cord
 Complex tangle of nerves that stretch from brain to tailbone
 Collects & transmits info between brain and peripheral nervous
system
 Also initiates reflexes: automatic responses to an event

5. Peripheral Nervous System
 PNS links the CNS to the organs, muscles, and glands of
the body
 PNS has two parts
 Somatic (SNS): nerves controlling voluntary muscle
movements
 Autonomic (ANS): controls glands, organs, blood vessels
 ANS has two parts
 Sympathetic: arouses body to prepare for action (fight or flight)
 Parasympathetic: slows down body to reserve energy

6. Sympathetic and Parasympathetic

7. The Neuron
 All brain activity originates with the neuron
 The messengers of the brain-world
 These cells receive signals from neurons or sense organs,
process the signals, and send them to other neurons, muscles,
or organs
 Three types
 Sensory: respond to sensory organ input
 Motor: send signals to muscles to control movement
 Interneurons: the go-between of sensory and motor neurons
 We have about 100 billion neurons
 Most, but not all, can be re-grown (severe spinal cord injury vs.
cutting your finger)

8. The Neuron

9. The Neuron: Structure
 Cell body: houses nucleus
 Cell Membrane: skin of the cell
 Axon: cable extending from the cell body
 Impulse from cell body travels along axon to its end, where
terminal buttons release neurotransmitters (chemical
messengers), received by other neurons
 Axon is covered by myelin sheath, which is composed of a fatty
substance that helps impulses travel the length of the axon
 Dendrite
 Branches extending from cell membrane that receive
neurotransmitters from other neurons

10. The Dendrite
 Increases receptive surface of the neuron
 Contacts occur along surface of dendrite

11. The Axon
 Axon hillock
 Myelin sheath
 Nodes of Ranvier
 The points just
between the myelin
sheaths

12. The Neuron in Action
 When a neuron receives impulses from other neurons, the
cell membrane allows open exchange of positively and
negatively charged ions
 Action potential (change in electrical charge) runs down axon
to terminal buttons
 This all starts with the axon hillock – the gatekeeper of the
neuron
 Terminal buttons release neurotransmitters
 Neurotransmitters cross the synaptic cleft to the dendrite of the
receiving neuron

13. The Neuron in action

14. Communication in the Neuron
 All-or-nothing
 The action potential either happens or it doesn’t
 Non-decremental
 Action potentials don’t change in amount (voltage) as they
travel
 Refractory period
 Neurons need 2ms to recover before they can transmit again
 Threshold
 The minimum level of stimulation required to trigger a neural
impulse
 Once you reach the threshold, the action potential doesn’t get
bigger

15. Important Neurotransmitters
 Acetylcholine (Ach)
 Slows down the body, memory, and attention (involved in Alzheimer’s
disease)
 Dopamine (DA)
 Voluntary movement, attention, and learning; high levels are
associated w/schizophrenia
 Endorphin
 Reduce sensitivity to pain; linked with pleasure (opiate-like)
 Serotonin
 Arousal, sleep; Prozac increases levels of serotonin
 Norepinephrine
 Helps control alertness and arousal; low levels can depress mood

16. History of Studying the Brain
 Franz Joseph Gall (1758 – 1828)
 Phrenology
 The study of the structure of the skull to determine a person’s
character and mental capacity
 26 ‘organs’ on the surface
of the brain

17. History of Studying the Brain
Phrenological
Map of the Skull

18. History of Studying the Brain
 Flourens (1794 – 1867)
 Emphasized the importance of experimental research of the
brain
 Carefully controlled experiments on animals to determine
localities of brain and their functions
 Moved the field of brain research into a more scientific arena

19. Areas of the Brain

20. Five Major Brain Areas
 CEREBRAL CORTEX is involved in your higher mental functions
of perceptual awareness, recognition and interpretation of sensory
stimuli (mostly based on memories).
 PREFRONTAL CORTEX is involved in your conscious thinking
processes, especially making choices by using your brainpower
 LIMBIC SYSTEM is involved in the expression of your instincts
and feeling processes, including your moods, since it includes your
hypothalamus and amygdala parts;
 CEREBELLUM is involved in your posture and many coordinated
movements;
 BRAINSTEM controls your body's most basic unconscious life-
sustaining functions, including your breathing and heartbeat.

21. Cerebral Cortex
 Two halves, four lobes
 Frontal lobe (seat of intelligence)
 Motor cortex (walking, chewing)
 Parietal lobe
 Sensory cortex
 Prosopagnosia (face blindness)
 Unilateral neglect (only realize half)
 Temporal lobe
 Auditory areas (opposite ear)
 Occipital lobe
 Visual areas (opposite eye)

22. Prefrontal Cortex
 The prefrontal cortex (PFC) is the very front of the brain,
located right beneath the forehead. It is in the anterior (front)
region of the frontal lobes.
 It is responsible for the executive functions, which include
mediating conflicting thoughts, making choices between
right and wrong or good and bad, predicting future events,
and governing social control — such as suppressing
emotional or sexual urges.
 The prefrontal cortex is the brain center most strongly
implicated in qualities like sentience, human general
intelligence, and personality.

23. Limbic System
 Hormonal system*
 Hypothalamus
 Feeding
 Reproductive behavior
 Temperature
 Hippocampus
 Memory
 Amygdala
 Feeding
 Memory
 Emotion

24. Cerebellum
 The cerebellum (Latin for little brain) is a region of the
brain that plays an important role in motor control. It is
also involved in some cognitive functions such as
attention and language, and probably in some
emotional functions such as regulating fear and
pleasure responses.

25. Brain Mapping
 How your brain is laid out. Actually, how any animals
brain is laid out.
 Two parts, linked together, but functioning as one
unit/different units.
 Distinct differences between hemispheres. Left
handed-ness or right handed-ness.

26. Left & Right Functions

27. Two Cerebral Hemispheres
 Contralateral arrangement
 Corpus callosum
 Thick band of nerve fibers connecting the hemispheres
 It’s how the 2 hemispheres communicate
 Right-brained vs. left-brained? Bicamerialism??
OR

28. Brain Stem
 Region of the brain where the spinal cord enters the skull
and swells
 Medulla
 Regulates heart-rate, breathing, blood pressure, and motor
movements
 Cerebellum
 Controls skilled motor movements

29. Brain Stem
 Pons
 Connects the two hemispheres of the cerebellum
 Reticular formation
 Sleep
 Attention
 Thalamus
 Relay center
 Filters & organizes information from senses

30. Preserve Your Brain
This is a “normal”
brain firing
This is a brain
that has just done
ecstasy