Download - WT 9e Chap 04
-
8/3/2019 WT 9e Chap 04
1/45
The brain:The source of mind and self
4
-
8/3/2019 WT 9e Chap 04
2/45
OverviewThe central nervous system
The peripheral nervous system
Communication in the nervous system
Chemical messengers in the nervous system
Mapping the brain
A tour through the brain
Two stubborn issues in brain research
4
-
8/3/2019 WT 9e Chap 04
3/45
The central nervous
systemBrain
Spinal cordA collection of neurons and
supportive tissue running from thebase of the brain down the center
of the back
Protected by spinal column
4
-
8/3/2019 WT 9e Chap 04
4/45
The withdrawal reflex4
-
8/3/2019 WT 9e Chap 04
5/45
Organization of the
nervous system4
-
8/3/2019 WT 9e Chap 04
6/45
Structure of a neuronDendrites
Receive information from other
neurons and transmit toward the
cell body
Cell body
Keeps the neuron alive and
determines whether it will fire
AxonExtending fiber that conducts
impulses away from the cell body
and transmits to other cells.
4
-
8/3/2019 WT 9e Chap 04
7/45
Types of neurons4
4
-
8/3/2019 WT 9e Chap 04
8/45
4Structure of a neuron
4
-
8/3/2019 WT 9e Chap 04
9/45
Your turnWhich part of a neuron is tree-like or branchy?
1. Dendrites
2. The axon
3. The cell body
4. The nucleus
4
4
-
8/3/2019 WT 9e Chap 04
10/45
Your turnWhich part of a neuron is tree-like or branchy?
1. Dendrites
2. The axon
3. The cell body
4. The nucleus
4
4
-
8/3/2019 WT 9e Chap 04
11/45
Neurons in the newsNeurogenesis
The production of new neurons
from immature stem cellsStem cells
Immature cells that renew
themselves and have the
potential to develop into maturecells
4
4
-
8/3/2019 WT 9e Chap 04
12/45
Stem-cell researchEmbryonic stem cells appear most useful yet federalfunding faces resistance from some advocates.
In 2001, President Bush signed executive orderpreventing creation of new cell lines.
Some scientists advocate for ban to be lifted because
stem cell research shows promise in helping thosesuffering from diseases of the brain.
4
4
-
8/3/2019 WT 9e Chap 04
13/45
How neurons
communicateAxon terminals releaseneurotransmitter.
Neurotransmitter enterssynapse.
Neurotransmitter binds to
receptors that it fits.
4
4
-
8/3/2019 WT 9e Chap 04
14/45
Action potentialA brief change in electrical voltage thatoccurs between the inside and outside of anaxon when a neuron is stimulated.
4
4
-
8/3/2019 WT 9e Chap 04
15/45
NeurotransmitterChemical released by a transmittingneuron at the synapse and capableof affecting the activity of a receiving
neuron
4
4
-
8/3/2019 WT 9e Chap 04
16/45
Major neurotransmitterSerotonin
Dopamine
Acetylcholine (Ach)
Norepinephrine
Gamma aminobutyric acid (GABA)
Glutamate
Endorphins
4
4
-
8/3/2019 WT 9e Chap 04
17/45
Opioids and Substance P4
4
-
8/3/2019 WT 9e Chap 04
18/45
The endocrine systemEndocrine glandsrelease hormonesinto the
bloodstream
4
Hormones regulate
growth, metabolism,
sexual developmentand behavior, and otherfunctions.
-
8/3/2019 WT 9e Chap 04
19/45
The endocrine system
4
-
8/3/2019 WT 9e Chap 04
20/45
HormonesMelatoninRegulates daily biological rhythms
Adrenal hormonesInvolved in emotions and stress
Cortisol, epinephrine, and norepinephrine
Sex hormonesRegulate development and functioning of reproductive organs
Androgens, estrogens, and progesterone
4
4
-
8/3/2019 WT 9e Chap 04
21/45
Mapping the brainLesioningInvolves damaging and removing sections of brain in
animals, then observing their effects.
4
4
-
8/3/2019 WT 9e Chap 04
22/45
ElectroencephalogramA recording of neural activity detected byelectrodes
4
4
-
8/3/2019 WT 9e Chap 04
23/45
Transcranial magnetic
stimulation (TMS)
Involves delivering a large current througha wire coil on a persons head
Can be used toProduce motor responses
Temporarily inactivate an area of the brain
Treat depression
4
4
-
8/3/2019 WT 9e Chap 04
24/45
Positron emission
tomography
Active areas have increasedblood flow.
Sensors detect radioactivity.
Different tasks show distinctactivity patterns.
4
A method for analyzing biochemical activity in the brain, usinginjections of a glucose-like substance containing a radioactiveelement
4
-
8/3/2019 WT 9e Chap 04
25/45
Magnetic resonance
imaging (MRI)
Magnetic fields align certainions and compounds.
When field is removed, thesemolecules release energy asradio waves.
Computer calculates tissuedensity from radio waves.
Provides clear 3D images
4
Method for studying body and brain tissue
4
-
8/3/2019 WT 9e Chap 04
26/45
A tour through the brainBrain stem
Cerebellum
ThalamusHypothalamus and pituitary gland
Amygdala
Hippocampus
Cerebrum and lobes of the cerebral cortex
4
4
-
8/3/2019 WT 9e Chap 04
27/45
The brain stemPonsInvolved in sleeping, waking,and dreaming
MedullaResponsible for certainautomatic functions such asbreathing and heart rate
Reticular activatingsystemArouses cortex and screensincoming information
4
4
-
8/3/2019 WT 9e Chap 04
28/45
The cerebellumRegulates movement andbalance
Involved in rememberingsimple skills and acquiredreflexes
Plays a part in
Analyzing sensory informationSolving problems
Understanding words
4
4
-
8/3/2019 WT 9e Chap 04
29/45
The thalamusRelays sensory messagesto the cerebral cortex
Includes all sensorymessages except thosefrom olfactory bulb
4
4
-
8/3/2019 WT 9e Chap 04
30/45
Hypothalamus and
pituitary gland
Involved in emotions anddrives vital to survivalFear, hunger, thirst, and reproduction
Regulates autonomicnervous system
Pituitary gland
Small endocrine gland which releases
hormones and regulates otherendocrine glands
4
4
-
8/3/2019 WT 9e Chap 04
31/45
The amygdalaResponsible forArousal
Regulation of emotion
Initial emotional response to sensory
information
Plays important role inMediating anxiety and depression
Emotional memory
4
4
-
8/3/2019 WT 9e Chap 04
32/45
The hippocampusResponsible forStorage of new information in memory
Comparing sensory information with
what the brain expects about the world
Enabling us to form spatial memories
for navigating the environment
4
4
-
8/3/2019 WT 9e Chap 04
33/45
The cerebrumLargest brain structure
Two cerebral hemispheres connected by the
corpus callosum.
In charge of most sensory, motor, andcognitive processes
Surrounded by cerebral cortex, a collection ofseveral thin layers of cells (gray matter)
4
4
-
8/3/2019 WT 9e Chap 04
34/45
Lobes of the cerebral
cortex
Occipital lobes (visual cortex)
Parietal lobes (somatosensory cortex)
Temporal lobesMemory, perception, emotion, and auditory cortex
Left lobe: Wernickes area
Frontal lobes
Emotion, planning, creative thinking, and motor cortexLeft lobe: Brocas area
4
4
-
8/3/2019 WT 9e Chap 04
35/45
Lobes of the cerebral
cortex
4
4
-
8/3/2019 WT 9e Chap 04
36/45
Your turnJenny bumps her head and is suddenly unable to see,
although the doctor says there is nothing wrong with her
eyes? Which part of her brain did Jenny damage?
1. The amygdala
2. The hippocampus
3. The occipital lobe of the cerebral cortex
4. The parietal lobe of the cerebral cortex
4
4
-
8/3/2019 WT 9e Chap 04
37/45
Your turnJenny bumps her head and is suddenly unable to see,
although the doctor says there is nothing wrong with her
eyes? Which part of her brain did Jenny damage?
1. The amygdala
2. The hippocampus
3. The occipital lobe of the cerebral cortex
4. The parietal lobe of the cerebral cortex
4
4
-
8/3/2019 WT 9e Chap 04
38/45
Phineas GageGage was a railroadconstruction foreman
An 1848 explosionforced a steel tampingrod through his head
Others said he wasno longer Gage
Lost his job, workedas a sideshow exhibit
4
4
-
8/3/2019 WT 9e Chap 04
39/45
The corpus callosumMillions of myelinatedaxons connecting thebrains hemispheres
Provides a pathway forcommunication
If surgically severed to
treat epilepsy,hemispheres cannotcommunicate directly
4
4
-
8/3/2019 WT 9e Chap 04
40/45
Split-brain experiment 4
4
-
8/3/2019 WT 9e Chap 04
41/45
Split-brain experiment
Subjects were presented information toone or the other side of their brains.
Patients identified verbally the pictures tothe right (e.g., boy).
When patients were asked to point to theface seen, the patients pointed to the leftpicture.
4
4
-
8/3/2019 WT 9e Chap 04
42/45
Allies or opposites?Research on split-brain patientsshows us. . .
4
Nearly all right-handed and the majority of left-handed
individuals process language mainly in the lefthemisphere.
Many researchers believe in left-hemisphere dominance.
Others insist right-hemisphere is important for spatialvisual problem solving, comprehending non-verbalsounds, and some language abilities.
4
-
8/3/2019 WT 9e Chap 04
43/45
Where is the Self?Modern brain scientists explain the mind orsoul in physical terms as a product of thecerebral cortex.Mind is a series of independent brain parts dealing with different
aspects of thoughts (Dennett 1991).Mind is a loose confederation of mental systems all workingwithout conscious awareness (Gazzaniga, 1998; Roser &Gazzaniga, 2004).
Frontal lobes may play a critical role.
Many still question the relationship betweensubjective experience and physicalprocesses of the brain.
4
-
8/3/2019 WT 9e Chap 04
44/45
4
-
8/3/2019 WT 9e Chap 04
45/45
What do differences
mean for behavior?
Supposed differences are stereotypes.
Brain difference does not necessarilyexplain behavior or performance.
Sex differences in the brain could be the
result rather than the cause of behavioraldifferences.
4