History of Neuropsychology
Overview of Topics
Very Early Developments
Early Solutions
Localization
The Crisis
Connectionism
Basic Concepts
Revised theory of localization
Luria's Approach
Mental Activity
concept of symptom
Very Early Developments
1. Aristotle - thought the mind was separate from the body & could not be destroyed.
2. Hippocrates - 400 B. C. -
a. Brain was organ of intellect.
b. Brain controlled senses & movement.
c. Lesion - contralateral effect.
d. Did not dissect skulls.
3. Herophilus - 3rd century B. C.
a. Brain - intellect
b. 3rd ventricle - cognition
c. posterior memory
d. 4th ventricle was seat of soul
4. Galen - 2nd century B. C. (influenced medical thought for 1000 years).
a. 1st experimental physiologist
b. Not ventricles but brain that was important.
c. Frontal lobes - seat of the soul.
5. Versalius - supported Galen's ideas initially but overcame it.
- mental functions in corpus alba.
6. Descarltes - soul in pineal gland.
7. Willis - 1664 - Mental functions in corpus striatum.
Early Solutions
1. Gall - 1758-1828
a. Faculties located in different organs or centers in the brain.
b. Centers in cortex were expansions of lower centers.
c. Centers were independent in function but able to interact.
d. Corpus collasum - joined the 2 hemispheres.
e. Phrenology
(1) based on idea that behavior (mind) can be divided into components (faculties)
(2) specific faculties related to specific cortical areas.
(3) use of faculty related to cell growth.
(4) growth produced buinp on skull.
f. Effector - more than one center could control its function.
g. Lateralization of motor function led to support for localization of function.
2. Spurzheim 1880's elaborated Galls theory
3. Flourens 1800's
a. First scientific studies related to brain function.
b. Found - brain functions as if composed of areas of specific functions.
c. But specific areas interact to function as a whole.
d. Ablation of pigeons & chickens.
e. Loss of function depends upon the extent of damage (equipotentiality).
4. Broca 1861
a. Expressive speech area.
b. Studied 8 patients. overall.
c. Posterior 1/3 of left inferior frontal gyrus "center for motor images of words."
d. First time a complex mental function - localized in a particular part of the cortex.
5. H. Jackson - 1868 postulated 2 types of language functions.
6. Bastian - 1869 - 2 interconnecting centers.
7. Wernicke - 1874 - receptive language related to posterior temporal cortex.
(idea that complex processes can be localized to specific brain areas aroused unprecedented enthusiasm.
a. "area for sensory images of words"
b. center for concepts - left inf. parietal.
c. center for writing - post left middle frontal gyrus.
d. many others
8. Meynert - "Frontal - motor - posterior sensory."
9. Lichtheim - 1885 - 7 types of speech.
10. Fritz & Hitzig - 1890 - motor areas.
Localization
1. With Gall's efforts localization came into vogue.
2. When he was refuted there appeared Broca & Wernicke to provide strong anatomical basis.
3. Overemphasis on localization from 1880 to 1930's.
4. Tendency was to narrowly localize functions.
5. Kleist 1934 - localized maps from gunshot wounds.
Idea that complex processes could be localized to specific brain areas aroused unprecedented enthusiasm.
a. center for concepts - left inferior parietal.
b. center for writing - posterior left middle frontal gyrus.
c. many others.
d. tendency was to narrowly localize functions.
The Crisis
1. Hughlings Jackson - resistant to localization.
a. approached the problem from the idea of level of construction rather than specific localization.
b. His ideas were too complex for the time.
2. Monakow, Head, Goldstein - many functions are the result of activity of the whole brain.
a. categoric behavior - highest level, dependent upon mass of brain rather than specific location.
3. Controversy between generalists and localizationalists
Generalist or Holists ( Equipotentiality)
1. Flourens data was there for a continual challenge.
2. Marie - 1906 - examined one of Broca's brains & found widespread damage attacking his theory.
3. Goldstein 1927, 44, 48 active in supporting holistic approach.
a. acknowledged localization but functions such as ability to deal with abstraction was total brain function.
4. During WWI localization was abandoned for holistic approach.
a. Localization based on Gall was destroyed (phrenology) & other became suspect.
b. Lashley - 1938 - found evidence for diffuse representation.
c. Gestalt psychology was influential.
d. Social & political influences were more important than newer scientific theories.
Connectionism
1. H. Jackson - emphasized levels of function.
2. Luria - discussed functional systems.
3. Geschwind - theory of brain function oriented toward connection.
There have thus evolved 3 theoretical camps: Mosicist, Holist, & Connectionist.
1. Mosicist - Localization
2. Holistic - Entire brain paticipates in all function.
3. Connectionist - combined view.
a. some functions are strongly localized other functions are the result of interconnections between various brain areas.
b. a function may be selectively localized in one hemisphere and diffuse relations exist with other hemisphere.
(1) Lashley's vision experiment.
c. most neurological syndromes are the result of interactions between 2 or more basic disorders.
(1) anatomical locus of lesion
(2) fibers of passage
A fresh Look at the Basic Concepts
1. Lesion research is directed at assessment of function of particular tissue.
2. Understand other organs by thinking of complete functional systems.
a. example of performance of movement may be accomplished by large number of ways.
b. example of writing - pen, pencil, right, left, etc.
Revision of the Concept of Localization
1. Ex. respiration - diaphragm, intercostal - larynx, etc.
a. first thought of respiratory center
b. Now found to be elusive, climbing up into the brain and down into the spinal cord and at present nobody can draw its boundaries at all accurately.
2. With other functions - "must be organized in systems of concertedly working zones, each of which performs its role in complex functional systems."
3. Vygotsky (60) - referred to "extracortical organization of complex mental functions"
a. conscious activity formed with the support of external aids.
4. Localization - never static or constant but moves about essentially during development.
a. at first requires many external aids and later becomes more automatic.
b. writing - first learn every letter
c. later converted into "kinetic melody".
d. later auditory and visual areas get involved
5. Theory of dynamic localization - a lesion in a particular part of the brain in a child has a systematic effect on the higher cortical areas superposed above it, a lesion in the same region in an adult affects lower zones of the cortex which now depend upon them. (acquisition vs. retention)
6. The task, then, is not to localize functions to limited areas but to ascertain which groups of concertedly working zones of the brain are responsible for the performance of complex mental activity; what contribution is made by each of these zones to the complex functional system, and how the relationship between these areas changes with development.
7. Such an approach necessitates a careful study of the structure of the psychological process studied.
Luria's Approach
1. Lesion research is directed at assessment of function of particular tissue.
2. Can best understand other organs by thinking of complete functional systems.
a. example - movement may be accomplished by large number of ways.
b. writing - pen, pencil, brush, right, left, foot, mouth. etc.
3. Revision of the concept of localization.
a. Respiration - first thought of center
b. Now found to be elusive
c. Climbing up into the brain and down into the spiral cord & at present nobody can draw its boundaries at all accurately.
FUNCTIONAL ORGANIZATION AND MENTAL ACTIVITY
1. How are neural processes organized which enable sensory input to be received, analyzed, stored, retrieved and used.
2. Shifted away from thinking of the brain as a series of passively responding devices whose function determined by past experience.
Now clear -- system is an active process
3. "Models of the brain" don't really help in obtaining truly scientific knowledge of the brain as the organ of behavior.
4. Avoid moving too fast lest we develop a baseless field based on premature schemes.
Progress must be based on real facts and real knowledge.
Neuropsychology - a new branch of science with the specific and unique aim of investigating the role of individual brain systems in complex forms of mental activity.
In past decades neuropsychology has become an important field of practical medicine with the consequent introduction of new methods to facilitate the early and more exact topical diagnosis of local brain lesions.
Revision of the concept of symptom
1. Study started with simplified assumption that a disturbance in function localized this missing function in the part of the brain destroyed.
2. If function is dependent upon several areas, a loss in one area may not abolish but only modify function.
3. Need detailed qualification of the symptom observed.
Syndrome Analysis
1. The functional system as a whole can be disturbed by a lesion of a very large no. of zones, and also that it can be disturbed differently in lesions in different locations.
2. Each area introduces its own particular factor essential to its performance.
3. Must first ascertain what factors are actually involved and what structures constitute its neuronal basis.
4. Teuber - principal of double dissociation of function -- (lesion disturbs some processes and leaves others intact).
