Friday, February 27, 2009

Quotes interesting from, about, re Luria and colleagues

Most taken from Human Brain and Psychological Processes

Gall was " a celebrated anatomist but an equally great dreamer. On a basis of incomplete observations and speculative conclusions he considered that faculties such as love of children, respect for parents, a sense of mental elevation or a feeling of self could be localized in circumscribed areas of the cerebral cortex" p.4

JC Eccles (1951) At what point does the mind "enter the brain" and begin to "interact with it"

"there is no evidence for isolated cerebral centers" Luria p.13

"A function which was initially shared by two people and bore the character of communication between them gradually crystallized and became a means of organization of the mental life of man himself" Vygotsky 1960 cf. p23

"The human brain does not contain any ready made mental faculties. The cerebral cortex is " the organ capable of making new functional organs." Le'ontiev 1961 p. 38

Deutsch (1953) summarized by Pribham (1960) cf p. 33 "Destruction or constant electrical stimulation of the hippocampus in animals leads to considerable disturbance of balanced behavior. Animals are unable to perceive signals giving information concerning its own erroneous reactions so that these are no longer corrected. The normal regulation of behavior is thus disturbed." Aden(1959) and Holmes and Adey (1960) did experiments of ele stimof hiipocampus showing same thing.

Sechenov-- idea that visual scanning was as important to visual perception as was reflection in retina

Yarbuss (1956) An object falling on a single point of retina ceased to be visualized after 2-3 seconds and to be kept as an image for longer than that the eye has to make small movements.

Analysis of Chinese writing bypasses phonology since writing incorporates idea of words rather than the sounds. Writing in Russian has many more mistakes if child is prevented from performing inner or silent speech while writing (Nazarova, 1952).

Structure of writing also changes during stages of learning to write versus already knowing how and doing it as an overlearned process.

Sechenov--1878 Mental processes fall into 2 categories: integration of elements in simultaenous groups, and placing elements in successive series. Simultaneous groups are essential for creating an adequate image of the outside world is generally associated with the visual, kinetic and vestibular apparatuses, responsible for the orientation of the body in space. Conversely, successive stimuli is primarily associated with the motor system on the one hand, and the acoustic system on the other.

Chronologic localization in development requires perfect concrete reflection of outside world (Perception = first signal) in order for speech (verbal semantics=second signal) to develop normally.

Vygotsky: In early development,the direction of dependence of psychological activities is bottom to top (primary simple processes are the basis for more complex ones) but in late stages its top to bottom . For example, a hearing deficit in a child will result in an inability to speak whereas in an adult it will not. Moreover, a lesion of the occipital cortex in a child will not give rise to optic agnosia alone or allowed the formation of other mental activity undisturbed.

A lesion of the brain at different stages of ontogenesis may have completely different consequences. Vygotsky's principle restated p. 62 " In a lesion of a particular 'center' in early childhood, the corresponding 'higher center' in closest relationship to it is secondarily affected, whereas in the case of a similar lesion in an adult it is the dependent lower 'center' that is primarily affected and the specific relationship between the centers is laid down during development. "The theory of constant specific functions of each organ is unsound " (Vygotsky, 1960 p 381.

"The concept (of localization) leads to pessimistic conclusions that the restoration of functions is completely impossible " p. 63. However these conclusions are contrary to the facts repeatedly observed.

Inhibition of wider area is Monakow's diaschisis. Luria interpreted diaschisis as meaning inhibition of the function of neurons situated within the focus and close to it, disturbing their synaptic conduction, and as a result the morphologically intact nerve cells become inactive. Pavlov interpreted the physiologic basis in terms of the theory in terms of limiting protective inhibition, and by Soviet neurologists in investigations of functional asynapsia (Graschchenkov 1946, 1948).

Those 2 studies above, plus others (Luria 1948, Perel'man 1946, Eidinova and Vinarskaya (1959) showed beneficial effects of prostigmine, eserine and galanthamine.

Lashley (1960) regarded speech as one of the most obvious examples of serially organized cerebral activity. Chomsky used Markov chains and mathematical principles to analyze serial or syntactic structures.

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