early ideas about brain and behavior l.
Skip this Video
Download Presentation
Early Ideas about Brain and Behavior

Loading in 2 Seconds...

play fullscreen
1 / 18

Early Ideas about Brain and Behavior - PowerPoint PPT Presentation

  • Uploaded on

Early Ideas about Brain and Behavior. Mind, Brain and Behavior. Neuroscientists want to unify the science of the mind with the science of the brain. Actions of the brain underlie all behavior. What we call mind is a range of functions carried out by the brain.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Early Ideas about Brain and Behavior' - marlon

Download Now An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
mind brain and behavior
Mind, Brain and Behavior
  • Neuroscientists want to unify the science of the mind with the science of the brain.
    • Actions of the brain underlie all behavior.
    • What we call mind is a range of functions carried out by the brain.
  • Neural science explains behavior in terms of brain activities.
  • Where does psychology fit?
where does mind reside
Where Does Mind Reside?
  • Which part of the body is the seat of the soul, the repository of memory?
  • Aristotle (384-322 B.C.) said the heart.
  • Hippocrates (460-379 B.C.) said the brain.
  • Galen (130-200 A.D.) agreed with Hippocrates:
    • Cerebrum vs cerebellum
    • Ventricles do the work
19 th century views
19th Century Views
  • By the 1800’s, the nervous system had been completely dissected and gross anatomy described.
  • Injury to the brain disrupts functioning.
  • Brain communicates with the body via nerves.
  • The brain has parts that probably perform different functions.
  • The brain follows laws of nature and operates like a machine.
understanding by analogy
Understanding by Analogy
  • Metaphors have always been drawn from discoveries in the physical world: fluid mechanics, windmills, man as machine.
  • Modern analogies:
    • Mind as switchboard
    • Mind as computer
discarded theories
Discarded Theories
  • Fluid in ventricles, flow of humors
    • Galen
  • Body as machine explained by mechanics
    • Nerves as hollow tubes full of gas or fluid
    • Descartes
  • Nerves as “wires”
    • Galvani, du Bois-Reymond, Muller, Helmholtz
the discovery of the neuron
The Discovery of the Neuron
  • Golgi developed a silver staining method that revealed the cell body and projections of the neuron.
  • Ramon y Cajal used the technique to show that neurons do not quite touch.
    • Neurons are a network of separate (discrete) cells that communicate.
  • Galvani showed that the signaling is electric.

Nissl Stain

Golgi Stain

localization vs distribution
Localization vs Distribution
  • Are specific functions carried out in specific regions of the brain?
  • Are functions an emergent property of brain activity as a whole?
  • Today’s neuroscience still debates this.
    • The answers appear somewhere between the two extremes.
two alternative views
Two Alternative Views
  • Cellular connectionism:
    • Individual neurons are the signaling elements of the nervous system, arranged in functional groups
    • Supported by empirical observations of Ramon y Cajal, Wernicke, Jackson, Sherrington.
  • The aggregate field view:
    • All regions of the brain participate in all mental functions.
    • Mind is NOT completely biological
the localization debate
The Localization Debate
  • Gall – the brain consists of 35+ organs corresponding to mental faculties.
    • Observable through bumps on the head.
    • Phrenology – anatomical basis for personology
  • Flourens – “…all perceptions, all volitions occupy the same seat…”
    • Aggregate field view
    • A reaction against strict materialism (mind not completely biological).
the discovery of localization
The Discovery of Localization
  • Imaging techniques that show the brain in action confirm that certain functions are carried out in specific areas of the brain.
  • This was difficult to see early on because of parallel processing
    • Each function is subserved by more than one neural pathway.
    • When one pathway is damaged, others may compensate, making localization harder to see.
support for the field view
Support for the Field View
  • Lashley found that the greater the lesions, the greater the impairment in functioning.
    • No matter where lesions were made, learning was impaired.
    • Mass action -- brain mass, not specific regions was most important to functioning.
  • Maze learning involves multiple functions, so it is unsuitable for studying localization.
the current view
The Current View
  • Functions consist of multiple processes that occur in specific areas of the brain.
    • Imaging studies reveal the different processes, called elementary operations.
    • Processing is both serial and parallel.
  • Even the simplest mental activity requires coordination of processes in multiple areas of the brain.
    • Such processing appears introspectively seamless.