INTRODUCTION -- HISTORY
Overview of Topics
Lesson Objectives
Early Developments
Philosophical Roots
Biological Roots
Contributions of Modern Psychology
Lesson Objectives --- Introduction
- Describe the significant early developments which contributed to our current understanding of brain-behavior relationships.
- Discuss the phrenology story and indicate the hypotheses that were correct versus those which wern't and explain why.
- What is the current status of the mind body problem?
- Explain the evidence for and against localization of function.
- Explain what Pierre Florens meant by equipotentiality.
Early Developments Related to Physiological Psychology
Aristotle: Thought the mind was separate from the body & could not be destroyed.
Hippocrates (400 BC):
a. Brain was organ of intellect.
b. Brain controlled senses and movement.
c. Lesion produces a contralateral effect.
Herophilus (3rd century BC):
a. Brain was organ of intellect.
b. Third ventricle responsible for cognition.
c. Fourth ventricle was seat of soul.
Galen (2nd century BC): Influenced medical thought for 1000 years.
a. First experimental physiologist.
b. Concluded it was not the ventricles but the brain that was important.
c. Frontal lobes was seat of soul.
Vesalius:
a. Initially supported Galen's ideas but overcame this thinking.
b. Thought mental functions were in corpus alba.
Willis (1664): Thought that the corpus striatum was responsible for mental functions.
Gall (1758-1828):
a. Faculties located in different organs or centers in the brain.
b. Centers in the cortex were expansions of lower centers.
c. Centers were independent in function but able to interact.
d. Corpus collosum joined the 2 hemispheres.
Phrenology:
a. Based on the idea that behavior (mind) can be divided into components (faculties).
b. Specific faculties related to specific cortical areas.
c. Use of faculty related to cell growth.
d. Growth produced a bump on the skull.
Spurzheim (1880's): Elaborated Gall's theory.
Philosophical Roots of Physiological Psychology
Animism: Basic theory that all things are controlled by animating spirits.
Mind-Body Question
- Dualism - belief that reality was divided into 2 categories: material & spiritual. (Thought mind and body were separate).
Descarte:
a. Believed ventricles controlled body via hollow tubes (nerves).
b. Pineal body was thought to be the controlling mechanism.
c. Thought the soul was in the pineal gland.
- Monism - belief that reality consists of an unified whole. (Belief that mind and body were the same.)
Free will - able to control our behavior; mind not constrained by physiology. In the lab must act like determinists (look for physical causes of behavior).
- Pluralism - mind, brain, and scientific knowledge.
Psychoneural Identity Hypothesis - mental and brain processes are one and the same (without brain there can be no mind).
Biological Roots of Physiological Psychology
Galvani - found that electrical stimulation of nerve caused muscle to contract. Even if separated from nerve, stimulation caused contraction.
Experimental Physiology
- Muller - first to advocate use of experimental techniques to physiology. Also developed the doctrine of specific nerve energies.
- Florens (1800's)
a. First scientific studies related to brain function.
b. Found that the brain functions as if composed of areas of specific function.
c. But specific areas interact to function as a whole.
d. Studying pigeons & chickens, he found that loss of function depends upon the extent of damage (equipotentiality).
- Broca (1861)
a. Investigated expressive language area in patient named Tan.
b. Studied 8 patients overall.
c. Found that the posterior 1/3 of the left inferior frontal gyrus functioned as the center for motor images of words
d. This was the first time that a complex mental function had been localized in a particular part of the cortex.
- H. Jackson (1868) Postulated two types of language functions.
- Wernicke (1874)
a. Discovered the receptive language area in the posterior 1/3 of the superior temporal cortex.
b. This area was identified as the area for the sensory images of words.
- Meynert - Frontal - motor and the posterior - sensory.
- Fritz & Hitzig (1890) - mapped the motor strip (pre-central gyrus of the frontal lobes).
- Helmholtz - measured speed of conduction of nerves (90 ft/sec)
- Localization
a. With Gall's efforts, localization came into vogue.
b. When his fourth point was refuted, there appeared Broca & Wernicke to provide strong anatomical basis for localization of function.
c. There was an overemphasis on localization from the 1880's to the 1930's.
- The Crisis
- Hughlings Jackson was resistant to localization.
a. He approached the problem from the idea of level of construction rather than specific localization.
b. His ideas were too complex for the time.
- Monakow, Head, & Goldstein
a. Many functions are the result of activity of the whole brain.
b. Categoric behavior - highest level, dependent upon mass of the brain rather than specific localization.
- Equipotentiality
- Flourens' data was there for continual challenge.
- Marie (1906) examined one of Broca's brains and found widespread damage attacking his theory.
- Goldstein (1927, 1944, 1948) acknowledged localization but stressed that brain functions such as ability to deal with abstraction resulted from the interctions of the brain as a whole.
- During WWII localization was abandoned for wholistic approach.
- Connectionism
- H. Jackson emphasized levels of function.
- Luria discussed functional systems.
- Geschwind held theory of brain function oriented toward connection.
- Functionalism: Natural selection and Evolution
- Functionalism - assumes characteristics of living organisms perform useful functions.
- Mutations - occur frequently and a few offer a selective advantage.
Contributions of Modern Psychology
The Goals of Research - Two forms of scientific explanation (generalization & reduction)
- Generalization - explain behavior as examples of general laws.
- Reduction - explain phenomena in terms of simpler phenomena.
- Levels of Analysis - cellular, intercellular, behavioral, and social.
Physiological research involve both generalization & reduction.
The Scientific Method:
Objectivity,
Observation,
Experimentation,
Controls,
Statistical Evaluation,
Independent verification of results.
The Value of Research with Animals
Terms to Know
| Aristotle |
dualism |
Meynert |
| Hippocrates |
monism |
Fritz & Hitzig |
| Herophilus |
pluralism |
Helmholtz |
| Galen |
Wernicke |
equipotentiality |
| Versalius |
Florens |
Geschwind |
| Willis |
Broca |
Goldstein |
| Gall |
Muller |
Luria |
| Phrenology |
H. Jackson |
psychoneural indentity hypothesis |
| Spurzheim |
Localization |
Generalization |
Links to Associated Areas