CHAPTER 2 : Behavioral Neuroscience Essentials of Psychology, by Saul Kassin ©2004 Prentice Hall...

CHAPTER 2:

Behavioral Neuroscience

Essentials of Psychology, by Saul Kassin

©2004 Prentice Hall Publishing

Behavioral NeuroscienceBehavioral Neuroscience

The Body’s Communication Networks

The Neuron

The Brain

Prospects for the Future

Kassin, Essentials of Psychology - ©2004 Prentice Hall Publishing

The Body’s Communication The Body’s Communication NetworksNetworks

The Nervous SystemThe Nervous System• Central Nervous System(CNS)

– The network of nerves contained within the brain and spinal cord

• Peripheral Nervous System(PNS)– The PNS comprises the somatic and

autonomic nervous systems


The Body’s Communication The Body’s Communication NetworksNetworks Divisions of the Nervous SystemDivisions of the Nervous System


The Body’s Communication The Body’s Communication Networks Networks

• Endocrine system: Ductless glands that regulate growth, reproduction, metabolism, mood, and some behavior.

• Hormones: Chemical messengers secreted into the bloodstream.

Major Endocrine GlandsMajor Endocrine Glands


The NeuronThe Neuron

• Neurons– Nerve cells that serve as the building blocks of the

nervous system

• Sensory Neurons– Neurons that send signals from the senses, skin,

muscles, and internal organs to the CNS

• Motor Neurons– Neurons that transmit commands from the CNS

to the muscles, glands, and organs


The NeuronThe Neuron

The Withdrawal ReflexThe Withdrawal Reflex


The NeuronThe Neuron The Structure of a NeuronThe Structure of a Neuron


The NeuronThe Neuron The Neuron in ActionThe Neuron in Action• Action Potential

– An electrical impulse that surges along an axon, caused by an influx of positive ions in the neuron

• Threshold– The level of stimulation needed to trigger an

action potential

• Neurotransmitters– Chemical messengers that transmit information by

crossing the synapse from one neuron to another


The NeuronThe Neuron How Neurons CommunicateHow Neurons Communicate

• Impulse releases neurotransmitter from axon terminals.

• Neurotransmitter enters synaptic gap.

• Neurotransmitter binds to receptors on the receiving neuron.


The NeuronThe NeuronNeurotransmittersNeurotransmitters

Major Neurotransmitters• Acetylcholine (ACh)

• Dopamine

• Endorphins

• Norepinephrine

• Serotonin• Gamma amino butyric acid (GABA)


The BrainThe BrainTools of Behavioral NeuroscienceTools of Behavioral Neuroscience

• Clinical Case Studies

• Experimental Interventions

• Electrical Recordings

• Brain-Imaging Techniques



Electroencephalogram (EEG)Electroencephalogram (EEG)

•An instrument used to measure electrical activity in the brain through electrodes placed on the scalp



Positron Emission TomographyPositron Emission Tomography– A visual display of brain

activity, as measured by the amount of glucose being used

• Radioactive isotopes (small amounts) are placed in the blood.

• Sensors detect radioactivity.

• Different tasks show distinct activity patterns.



Magnetic Resonance ImagingMagnetic Resonance Imaging

– A brain-imaging technique that uses magnetic fields and radio waves to produce, clear three-dimensional images


Regions of Regions of the Brainthe Brain

The BrainThe Brain


The BrainThe BrainRegions of the BrainRegions of the Brain

The BrainstemThe Brainstem• Medulla– Vital involuntary

functions

• Pons– Sleep and arousal

• Reticular formation– Sleep, arousal,

attention

• Cerebellum– Motor coordination



The Limbic SystemThe Limbic System • Thalamus

– Sensory relay station

• Amygdala– Fear, anger, and

aggression

• Hippocampus– Memory formation

• Hypothalamus– Regulates glands,

autonomic NS


The BrainThe BrainRegions of the BrainRegions of the Brain The Cerebral Cortex in AnimalsThe Cerebral Cortex in Animals

•The outermostcovering ofthe brain, largelyresponsible for higher-ordermental processes


The BrainThe BrainRegions of the BrainRegions of the Brain The Four Lobes of the Cerebral CortexThe Four Lobes of the Cerebral Cortex


The BrainThe BrainRegions of the BrainRegions of the Brain Within the Lobes of the Cerebral Cortex Are:

• The Somatosensory Cortex– Receives sensory information

• The Motor Cortex– Sends impulses to voluntary muscles

• The Association Cortex– Houses the brain’s higher mental processes


The Somatosensory and Motor AreasThe Somatosensory and Motor Areas



Language ProcessingLanguage Processing• Broca’s Area

– Located in the left hemisphere, directs the muscle movements in speech production

• Wernicke’s Area– Located in the left

hemisphere, involved in the comprehension of language The brain operates as

an integrated system.Kassin, Essentials of Psychology - ©2004 Prentice Hall Publishing

The BrainThe BrainThe Split BrainThe Split Brain

The Corpus CallosumThe Corpus Callosum

– A bundle of nerve fibers that connects the left and right hemispheres

• If surgically severed for treatment of epilepsy, hemispheres cannot communicate directly.



Visual ProcessingVisual Processing• Both eyes send

information to both hemispheres.

• Images in the right half of the visual field go to the left hemisphere.

• Images in the left half of the visual field go to the right hemisphere.



Sperry’s Split-Brain ExperimentSperry’s Split-Brain Experiment

• Split-brain subjects could not name objects shown only to the right hemisphere.

• If asked to select these objects with their left hand, they succeeded.

• The left hemisphere controls speech, the right does not.



The Talking Left HemisphereThe Talking Left Hemisphere

• Brighter areas indicate higher activity levels.

• When hearing words, for example, auditory cortex and Wernicke’s area are the most active.



Neglect SyndromeNeglect Syndrome• A patient with a stroke

in the right hemisphere was asked to copy the drawings.

• Typical of neglect syndromes, the left side of the model is almost completely ignored.


Prospects for the FutureProspects for the Future

• Plasticity– A capacity to change as a result of

experience

• Richer environments lead to heavier, thicker brains, more synapses, and better learning.

• The cost of plasticity is the case of the phantom limb.

The Brain’s Capacity for Growth & Reorganization


Prospects for the FutureProspects for the Future

• Neurogenesis– The production of new brain cells

• Neural Graft– Technique of transplanting healthy tissue

from the nervous system of one animal into that of another

The Brain’s Capacity for Growth & Reorganization


CHAPTER 2 : Behavioral Neuroscience Essentials of Psychology, by Saul Kassin ©2004 Prentice Hall...

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