@Holiday20310401,
Holiday20310401 wrote:Benjamin Libet did that famous experiment which suggested (or proved, I dunno) that the brain predetermined the outcome of the awared thought because there was preceding brain activity before the awareness.
... does it? ... I can't say that I've read Libet's original papers, but Wegner spends several pages discussing Libet's and others' experiments in
The Illusion of Conscious Will ... here's an interesting passage from an experiment where subjects were asked to press a button as soon as they felt a tap:
Quote:Jenson (1979) asked people to try to deliberately to lengthen their reaction time little by little and found that they could not do so. Rather, their reaction times jumped from the usual minimum values (in this study, about 250 milliseconds) to much higher values, which at a minimum were 500 to 1000 milliseconds. One cannot slow down one's reaction until one becomes concious of the stimulus and of having reacted, and this takes lots of time. This suggests that a response and a conscious response are two very different things, the first one far speedier than the second.
... the interesting aspect here is that the experimental subjects were able to slow down their response times
at all! ... that is, if it takes only 250ms to respond and 500ms to become conscious of the response,
the response should already be done and over with before the subject has a chance to consciously slow the response! ... this leads to the following interpretation of these experiments:
Experiement I: Respond as fast as you can
1. The experimenters instruct the subjects that they need to respond as fast as they can to the stimulus
2. Having been told this, the subject's conscious will "primes" the unconscious for automatic execution of the response
3. When the stimulus is applied, the unconscious automatically responds and the conscious will is notified of the response
Experiment II: Consciously delay your response
1. The experimenters instruct the subjects that they need to consciously delay their response
2. Having been told this, the subject's conscious will cannot "prime" the unconscious for automatic execution of the response, else the response will be over before they can consciously delay it
3. When the stimulus is applied, it needs to be consciously perceived before the conscious will can initiate a response
This also leads to an alternative interpretation of Libet's original experiments in which the subjects were asked to spontaneously move a finger and simultaneously report the time at which they consciously willed the finger to move:
1. The experimenters instruct the subject on what to do
2. Having been told this, the subject's conscious will "primes" the unconscious for automatic finger movement at a spontaneous point in time in the future
3. At a spontaneous point in time in the future, the unconscious automatically initiates finger movement and then notifies the conscious will of said initiation
... so conscious will may play more of a leading role in these experiments than initially thought.
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