View
221
Download
0
Tags:
Embed Size (px)
Citation preview
Chapter 2
Neural Communication & The Brain
Psychology 101
Sara J. Buhl
Phrenology (1800s)Phrenology (1800s)
Neural CommunicationNeural Communication Biological Psychology
branch of psychology concerned with the links between biology and behavior
Neuron a nerve cell the basic building block of the nervous system
Neural CommunicationNeural Communication
Neural CommunicationNeural Communication Dendrite
the branching extensions of a neuron that receive messages and conduct impulses toward the cell body
Axon the extension of a neuron, through which messages
are sent to other neurons or to muscles or glands
Myelin Sheath a layer of fatty cells covering the axon of some
neurons greatly increases the speed of neural impulses
How do neurons How do neurons communicate?communicate?
Synapse junction between the axon tip of the sending neuron
and the dendrite or cell body of the receiving neuron tiny gap at this junction is called the synaptic gap or
cleft
Neurotransmitters chemical messengers that cross the synaptic gaps
between neurons when released by the sending neuron,
neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether it will generate a neural impulse
NeurotransmissionNeurotransmission
NeurotransmittersNeurotransmitters
Acetylcholine – Enables muscle action, learning, and memory
Dopamine – Influences movement, learning, attention, and emotion
Serotonin – Affects mood, hunger, sleep, and arousal
Endorphins – opiatelike neurotransmitters linked to pain control and to pleasure
Neural CommunicationNeural Communication
Neural CommunicationNeural Communication
Serotonin pathways
The Nervous SystemThe Nervous System
Central Nervous System (CNS) the brain and spinal cord
Peripheral Nervous System (PNS)
the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body
Peripheral Nervous Peripheral Nervous SystemSystem
Autonomic Nervous System the part of the peripheral nervous system that
controls the glands and the muscles of the internal organs (e.g., heart)
Two Parts: Sympathetic Nervous System
part of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations
Parasympathetic Nervous System Part of the autonomic nervous system that calms the
body, conserving its energy
Central Nervous Central Nervous SystemSystem
Spinal Cord – information highway; connects the peripheral nervous system to the brain
The Brain – enables the mind – seeing, hearing, smelling, feeling, remembering, thinking, speaking, dreaming.
ReflexReflex
a simple, automatic, inborn response to a sensory stimulus
The BrainThe Brain Brainstem
the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull
responsible for automatic survival functions
Medulla base of the brainstem controls heartbeat and breathing
The Brainstem and ThalamusThe Brainstem and Thalamus
The BrainThe Brain
Thalamus on top of brainstem the brain’s sensory switchboard
Reticular Formation a nerve network in the brainstem plays an important role in
controlling arousal
Electroencephalogram Electroencephalogram (EEG)(EEG)
an amplified recording of the waves of electrical activity that sweep across the brain’s surface
these waves are measured by electrodes placed on the scalp
MRI ScanMRI Scan
The BrainThe Brain
Cerebellum the “little brain” attached to the rear of the
brainstem it helps coordinate voluntary movement and
balance injury results in difficulty walking and keeping
balance; movements would be jerky and exaggerated
The BrainThe Brain
Limbic System a doughnut-shaped system of neural structures at
the border of the brainstem and cerebral hemispheres
associated with emotions such as fear and aggression and drives such as those for food and sex
includes the hippocampus (ch. 8), amygdala, and hypothalamus.
The Limbic System
The Limbic SystemThe Limbic System
Amygdala two almond-shaped neural
clusters that are part of the limbic system
linked to emotion influence aggression and fear
The Limbic SystemThe Limbic System
Hypothalamus neural structure lying below (hypo) the
thalamus directs several maintenance activities
eating drinking body temperature
helps govern the endocrine system via the pituitary gland
linked to emotion
The Limbic SystemThe Limbic System Electrode implanted in reward center of hypothalamus
The Cerebral CortexThe Cerebral Cortex
Cerebral Cortex (Cerebrum) the intricate fabric of interconnected neural cells
that covers the cerebral hemispheres the body’s ultimate control and information
processing center
Left & Right Hemispheres of the Cerebrum Left hemisphere receives input from & controls
the right side of the body Right hemisphere receives input from & controls
the left side of the body
The Cerebral CortexThe Cerebral Cortex
The Cerebral CortexThe Cerebral Cortex
Frontal Lobes Involved in speaking & muscle movements Important for planning and making judgments Damage can alter personality (e.g., Phineas
Gage)
Parietal Lobes Receives sensory input for touch and body
position
The Cerebral CortexThe Cerebral Cortex
Occipital Lobes
include the visual areas, each of which receives visual information from the opposite visual field
Temporal Lobes
include the auditory areas, each receives auditory information primarily from the opposite ear
The Cerebral CortexThe Cerebral Cortex
Functional MRI scan of the visual cortex activated by looking at faces
Brain ReorganizationBrain Reorganization
Plasticity the brain’s capability to
reorganize following damage (especially in children) and in experiments on the effects of experience on brain development
Brain ReorganizationBrain Reorganization
Corpus Callosum large bundle of neural fibers
connecting the two brain hemispheres and carrying messages between the hemispheres
Split Brain a condition in which the two
hemispheres of the brain are isolated by cutting the connecting fibers (mainly those of the corpus callosum) between them
Brain ReorganizationBrain Reorganization
Left visual field
Right visual field
Testing the divided Testing the divided brain:brain: