Outlines of physiological psychology : A text-book of mental science for academies and colleges / by George Trumbull Ladd.

  • George Trumbull Ladd
Date:
1891 [©1890]
Catalogue details

Licence: Public Domain Mark

Credit: Outlines of physiological psychology : A text-book of mental science for academies and colleges / by George Trumbull Ladd. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    attenuated line, with no ])readtli or possible variation in breadth, is most misleading; and yet this form of represen- tation has been the accepted one with a large number of English psj^chologists. If we are to assist our imaginations to a knowledge of the truth by such partially inapt figures of speech, it is better to represent the field of conscious- ness by a series of overlapping circles having a large pos- sible variation in their diameters; or by what we see of change in a kaleidoscope when we turn it slowly before the eye. The Physical Basis of Consciousness. — Little can be added on this point to what has already been said regarding the physical basis of the different forms of consciousness. It has been concluded that, in man's case, the cerebrum is probably the sole, as it is certainly the chief, organ of consciousness (see p. 179 f.). By this we can mean nothing intelligil)le, however, except this: that the constitution and molecular changes of the nervous matter of the cere- brum are the only immediate antecedents or concomitants of the phenomena of consciousness; and so that, whatever takes place in the body outside of the cerebrum has an effect upon consciousness only in case it gets itself represented, as it were, within that supreme organ. A recent writer (Herzen) holds that the physical basis of consciousness rests on the biological law which condi- tions the activity of a tissue on its decomposition and ensuing regeneration. The intensity of consciousness, as a neural function, depends on the intensity of the decompo- sition of the brain tissue ; and it is inversely as the ease and rapidity with which the inner work of one nerve-ele- ment is transmitted to another. This theory explains some facts. It does not appear, however, that the amount of the work of decomposition in the brain-tissue is a measure of the breadth, height, and depth, of the field of con- sciousness.