The Brain
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Lesion
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tissue destruction
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a brain lesion is a naturally or experimentally
caused destruction of brain tissue
Electroencephalogram (EEG)
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an amplified recording of the waves of
electrical activity that sweep across the brain’s surface
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these waves are measured by electrodes placed on
the scalp
Event Related Potential: ERP
PET Scan: detects where a radioactive
form of glucose goes while the brain performs a given task
MRI Scan (magnetic
resonance imaging)
a technique that uses magnetic fields and radio waves to produce
computer-generated images that distinguish among different types of soft tissue
MRI
Functional MRI (fMRI)
The Brain
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Brainstem
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the oldest part and central core of the brain,
beginning where the spinal cord swells as it enters the skull
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responsible for automatic survival functions
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Medulla
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base of the brainstem
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controls heartbeat and breathing
The Brainstem
Brainstem
Brainstem
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Reticular Formation
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a nerve network in the brainstem that plays an
important role in controlling arousal
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Circadian Rhythms
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Thalamus
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the brain’s sensory switchboard, located on top
of the brainstem
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it directs messages to the sensory receiving
areas in the cortex and transmits replies to the cerebellum and medulla
Brian Stem
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Cerebellum
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the “little brain” attached to the rear of the
brainstem
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it helps coordinate voluntary movement and
balance
The Limbic System
Limbic System
The Brain
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Limbic System
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a doughnut-shaped
system of neural structures at the border of the brainstem and cerebral
hemispheres
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associated with
emotions such as fear and aggression and drives such as those for food and
sex
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includes the
hippocampus, amygdala, and hypothalamus.
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Amygdala
[ah-MIG-dah-la]
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two almond-shaped
neural clusters that are components of the limbic system and are linked to
emotion
The Limbic System
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Electrode implanted in reward center
The Brain: Limbic System
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Hypothalamus
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neural structure lying below (hypo) the
thalamus; directs several maintenance activities
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eating
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drinking
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body temperature
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helps govern the endocrine system via the
pituitary gland
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is linked to emotion
The Cerebral Cortex
The Cerebral Cortex
Nobel Prize Winners: Hubel &
Weisel
Hubel and Wiesel
Hubel and Weisel
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There are cell that fire to only vertical lines
o
Others fire to only horizontal lines
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Others fire on to specific types of movements,
etc.
The Cerebral Cortex
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Functional MRI scan shows the visual cortex
activated as the subject looks at faces
The Cerebral Cortex
Temporal Lobe
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Visual perception, object recognition,
categorization
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Face Recognition: Face Fusiform Area (mainly the
right side)
Temporal Lobes
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Auditory perception, especially language and
names
Temporal Lobes
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Hippocampus– Transfer of information from STM to
LTM
The Cerebral Cortex
Parietal Lobe
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Integration of sensory information
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Integration of information and body knowledge
Parietal Lobe: Body knowledge
The Cerebral Cortex
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Motor Cortex
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area at the rear of the frontal lobes that
controls voluntary movements
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Sensory Cortex
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area at the front of the parietal lobes that
registers and processes body sensations
The Cerebral Cortex
The Cerebral Cortex
Frontal Lobe
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Higher Order Functions
n
Problem Solving
n
Reasoning
o
Planning and Executive Function
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Consciousness and Awareness
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Impulse Control
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Knowledge of time (past, present, future)
Association Areas
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More intelligent
animals have increased “uncommitted” or association areas of the cortex
Our Divided Brain
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Corpus Callosum
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large band of neural fibers
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connects the two brain hemispheres
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carries messages between the hemispheres
Split Brain
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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
Split Brain