Promoters of activity

Usage examples of stimuli.

The larger the neopallium, which is the center of a great variety of coordinations among stimuli and responses, the more complex the potentialities of behavior.

When two stimuli occur together, one of them, occurring afterwards, may call out the reaction for the other also.

In fact, it is not an isolated stimulus that leaves an engram, but the totality of the stimuli at any moment.

The observable fact is that, when a certain complex of stimuli has originally caused a certain complex of reactions, the recurrence of part of the stimuli tends to cause the recurrence of the whole of the reactions.

What we observe is that certain present stimuli lead us to recollect certain occurrences, but that at times when we are not recollecting them, there is nothing discoverable in our minds that could be called memory of them.

Otherwise we shall be compelled to believe that all our knowledge, all our store of images and memories, all our mental habits, are at all times existing in some latent mental form, and are not merely aroused by the stimuli which lead to their display.

The second point concerns the relating of our point of view to that which regards sensations as caused by stimuli external to the nervous system (or at least to the brain), and distinguishes images as "centrally excited," i.

It is clear that a sufficiently ingenious person could manufacture a machine moved by olfactory stimuli which, whenever a dog appeared in its neighbourhood, would say, "There is a dog," and when a cat appeared would throw stones at it.

The factors open to external observation are primarily habits, having the peculiarity that very similar reactions are produced by stimuli which are in many respects very different from each other.

A good instrument, or a person with much knowledge, will give different responses to stimuli which differ in relevant ways.

This boy and weather-cock have the opposite defect to that of the previous pair: they give different responses to stimuli which do not differ in any relevant way.

Omitting some of the niceties of our previous discussion, we may say that an instrument is ACCURATE when it avoids the defects of the two boys and weather-cocks, that is to say, when-- (a) It gives different responses to stimuli which differ in relevant ways.

It is clear that knowledge is displayed by accuracy of response to certain kinds of stimuli, e.

There are, nevertheless, three types of stimuli that will bring about depolarization without injuring the cell (if the stimuli are sufficiently gentle).

At periodic intervals along the length of the cords, there emerge nerves that receive stimuli from or deliver impulses to various specific body regions.