Download Brain and Behavior

Brain and Behavior
Chapter 1
Interview with Rodney Brooks
Human as machine, machine as human:
http://www.aaai.org/AITopics/html/show.html
http://news.bbc.co.uk/olmedia/cta/progs/02/hardtalk/brooks19aug.ram
Organizational Principles
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Two hemispheres – left, right
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Each with four distinct lobes:
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Frontal – thinking, planning, control of movement
Parietal – tactile sensation, body image, space
Occipital – vision
Temporal – hearing, learning and memory, emotion
Each lobe has folds:
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Gyri (gyrus) – crests (flat areas)
Sulci (sulcus) – grooves (areas folded in)
Organization (Cont.)
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Contralateral control:
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The left hemisphere controls the right side of the
body.
The right hemisphere controls the left side of the
body.
Sensory information from one side of the body is
interpreted by the opposite brain hemisphere.
Some brain functions are localized to a
hemisphere.
Localization of Language
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Aphasia – a difficulty of language caused by
brain injury (such as with stroke).
Broca – described patients who can
understand language but not speak.
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Results from damage to Broca’s area.
Wernicke – described patients who can speak
but not understand language.
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Results from damage to Wernicke’s area.
A Language Circuit
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Wernicke’s areas and Broca’s areas are part of
a connected circuit for receiving and
producing language.
Wernicke predicted conduction aphasia – a
disorder produced by breaking the connection
between the two regions.
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Results in paraphasia – omitting and substituting
parts of speech. Also, inability to repeat phrases.
Brodmann Areas
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Different areas of the brain with different
functions have different kinds of neurons.
Brodmann mapped the areas based on the
kinds of cells found:
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Cytoarchitectonic method
52 functionally distinct areas identified by
number.
Evolution and Neuroscience
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Darwin’s theory of natural selection states that
modern species of organisms evolved from a
common ancestor.
Animal models can be used because there are
important similarities with humans.
Specialization for an environmental niche
means there are also important differences.
Today animal welfare is closely monitored.
Levels of Analysis
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The reductionist approach breaks the brain
into smaller pieces for study:
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Molecular -- what molecules do
Cellular – how molecules work together in cell
Systems (vision, motor) – circuits that perform a
common function
Behavioral – how systems work together to
produce integrated behaviors
Cognitive – neural mechanisms of mental activity
Understanding Disorders
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An important goal of neuroscience is finding
treatment, prevention, or cure for serious
disorders:
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Alzheimer’s disease -- dementia
Parkinson’s disease –voluntary motor movement
Depression – 30,000 suicides per year
Schizophrenia – disrupts cognition, personality
Stroke
Alcohol & drug addiction