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The Cerebral Cortex
• Controls voluntary movement and cognitive
functions
• 4 lobes: frontal, temporal, occipital, parietal
– Frontal: association area, motor cortex,
Broca’s area (speech), motor cortex
– Temporal: hearing, auditory association
area, smell, Wernicke’s area (understanding
language)
– Occipital: Vision, Vision association area
– Parietal: Taste, reading, somatosensory
cortex, somatosensory association area
• Evolution: increase in size of the neocortex
= expansion of the association areas that
integrate higher cognitive functions and
make more complex behavior and learning
possible
Information Processing
• Based on the integrated sensory
information, the cerebral cortex may
generate motor commands that
cause specific behaviors.
– Action potentials in the primary
motor cortex travel along axons to
the brainstem and spinal cord 
motor neurons  skeletal muscle
cells
– The cortical surface area devoted to
each body part is related to the
number of sensory neurons that
innervate that part or to the amount
of skill needed to control muscles in
that part
• Phantom limb (plasticity- brain
reorganizes)
Lateralization
• Lateralization: segregation of functions in the
cortex of the left and right hemispheres of the
brain.
• Left: more adept at language, math, logical
operations, and the serial processing of sequences
of information
• Right: pattern recognition, face recognition, spatial
relations, nonverbal thinking, emotional
processing, simultaneous processing
• Working together: corpus callosum
– Split brain (control epileptic seizures)
HE•ART
Emotions
• Limbic system – central to some of
the behaviors that distinguish
mammals from most reptiles and
amphibians
– Amygdala (fear & aggression)
• Recognize emotional content – facial
expressions
– Hippocampus (encoding long term
memories)
• Mild shock  autonomic arousal
– Olfactory bulb (thalamus &
hypothalamus)
– Ex. Phineas Gage: frontal lobe damage
Memory and Learning
• Short-term memory: (frontal lobes)
the ability to hold information,
anticipations, or goals for a time
and then release them if they
become irrelevant
• Long-term memory: (hippocampus)
the ability to hold, associate, and
recall information over one’s life
• long-term potentiation (LTP): an
enhanced respnsiveness to an
action potential (nerve signal) by a
receiving neuron
– Kandel’s sea hare studies on the
cellular basis of learning see p. 1036
Diseases and Disorders
• Schizophrenia: a severe mental disturbance
characterized by psychotic episodes in which
patients lose the ability to distinguish reality.
About 1% of the world’s pop. suffers from this
– Symptoms: hallucinations, delusions, blunted
emotions, distractibility, lack of initiative, poverty
of speech
– Cause: unknown… most likely genetic, linked to
glutamate receptors
– Treatment: dopamine pathways
Diseases and Disorders
• Depression
– Bipolar disorder: involves swings of moods from
high to low and affects 1% of the world’s
population
– Major depression: low mood most of the time;
5% of the population
– both have genetic component
– Treatments: drugs- Prozac, electroconvulsive
therapy, lithium administration, talk therapy
Diseases and Disorders
• Alzheimer’s Disease: mental deterioration, dementia,
characterized by confusion, memory loss
– age related: 10% at age 65, 35% at age 85
– Neurons die in the brain  brain shrinkage
• Neurofibrillary tangles- degenerated neuronal and glial processes
• Parkinson’s Disease: a motor disorder characterized by
difficulty in initiating movements, slowness of
movement, and rigidity
– death of neurons in a midbrain nucleus called the
substantia nigra
– Degeneration of dopamine neurons
• L-Dopa