Transcript Griggs Chapter 2: Neuroscience

General Psychology (PY110)
Chapter 2
Neuroscience
Neuroscience and Behavior
 All sensory
– Receptors
organs
 Muscles and
– Effectors
Glands
 Neurons
– Communication channel
The Structure of a Neuron
How Neurons Communicate
Communication
within
a neuron is
electrical
Communication
between
neurons is
chemical
Types of Neurons
Interneurons exist only in the central
nervous system
 Sensory neurons carry information to the
central nervous system from sensory
receptors in the eyes, muscles, and glands
 Motor neurons carry movement commands
from the central nervous system to the rest of
the body

Neurotransmitters,
Drugs, and Poisons
Key terms:
Agonists
Drugs and poisons
that increase the
activity of one or more
neurotransmitters
Antagonists
Drugs and poisons
that decrease the
activity of one or more
neurotransmitters
Neurotransmitters
1. Acetylcholine (ACh) is involved in both learning and
memory and muscle movement
2. Dopmaine impacts our arousal and mood states, thought
processes, and physical movement
3. Serotonin and norepinephrine are neurotransmitters
involved in levels of arousal and mood, and play a major role in
mood disorders such as depression
4. GABA is the main inhibitory neurotransmitter in the nervous
system; glutamate is the main excitatory neurotransmitter
5. Endorphins are a group of neurotransmitters that are involved
in pain perception and relief
Dopamine
Low levels are associated
with Parkinson’s disease,
and excessively high levels
are associated with schizophrenia
 L-Dopa is an agonist that increases production of dopamine
 Anti-psychotic drugs are antagonists that block the
receptor sites for dopamine so that this neurotransmitter
cannot send its messages
 Amphetamine acts as an agonist by stimulating the release
of dopamine from axon terminals
 Cocaine is an agonist that blocks the re-uptake of dopamine

Nervous System Subdivisions
The Central Nervous System
Consists of the spinal cord and the brain
◦ The spinal cord has two functions
 Conduit for incoming sensory data
and outgoing movement
commands
 Provides for spinal reflexes, which
are simple automatic actions not
involving the brain
◦ The brain is the control center for
the entire nervous system
The Peripheral Nervous System
Consists of two parts:
◦ The somatic (or skeletal) nervous system carries
sensory input from receptors to the CNS and relays
commands from the CNS to the skeletal muscles to
control their movement
◦ The autonomic nervous system regulates our internal
environment and consists of two parts
 The sympathetic nervous system is in control when
we are very aroused and prepares us for defensive action
(such as running away or fighting)
 The parasympathetic nervous system is in control
when the aroused state ends to return our body to its
normal resting state
Components of Emotion
An emotion is a complex psychological
state that involves three components:
Physical
Behavioral
Cognitive
A physiological
state of arousal
triggered by the
autonomic
nervous system
An outward
expression including
facial expressions,
movements and
gestures
An appraisal of the
situation to determine
which emotion we are
experiencing and how
intensely
Emotion Theory Comparison
•James-Lange Theory
Stimulus:
Sight of bear
Physiological
Arousal
Emotional
Response (Fear)
•Cannon-Bard Theory
Stimulus:
Sight of bear
Emotional
Response (Fear)
Physiological
Arousal
•Schachter-Singer Theory
Stimulus:
Sight of bear
Physiological
Arousal
Cognitive
Appraisal
Emotional
Response (Fear)
The Central
Core Brain
Structures
The Limbic System
The Four Lobes and the
Sensory-Motor Processing Areas
The Case of Phineas Gage
Phineas Gage was railroad worker
who survived when a metal tamping
iron flew through his left cheek and
head, exiting through his frontal
lobes
 He became irresponsible, impulsive,
disorderly, indecisive, and cursed,
leading neuroscientists to think the
frontal lobes are important in such
behaviors

Language
What we know…

Left hemisphere
◦ Language
◦ Math and logic skills
◦ More analytical,
analyzing wholes into
pieces

Right hemisphere
◦ Spatial perception
◦ Solving spatial
problems
◦ Drawing
◦ Face recognition

A band of neurons called the Corpus Callosum
joins the two hemispheres
◦ Allows communication and coordinates functions
Five
Stages of
Sleep
Brain wave taken by
Electroencephalogram
(EEG)
Sleep
Cycles
•Cycles last
about 90
minutes.
•4-6 cycles each
night
Nature of Sleep & Dreams
Stage Wave Form
Remarks
Sleep (Hrs) Awake (Hrs)
Adults 1
Babies 2
8 Alpha & Theta16 ‘Falling’ asleep
16 Theta
8 Light sleep
Non – 3
REM 4
Delta
3
Delta
2
Theta
REM
% REM
Delta
Deep Sleep
- Night terrors, Sleep walking, Sleep
talking, Etc.
Light sleep
Paradoxical Sleep
- Dreaming occurs
2 Types of Sleep – REM and Non-REM
 Non-REM = Quantity
REM = Quality
 REM Sleep reduced by alcohol and sleeping pills
 Sleep Deprivation (or Dream Deprivation)

◦ Moderate – Sleep rebound
◦ Severe – depression, impaired memory, decreased immune response

Circadian cycles – Biological clock