In 2003, he was the first recipient of the Virtual Nobel Prize in Psychology from the University of Klagenfurt "for his pioneering achievements in the experimental investigation of consciousness, initiation of action, and free will".

His initial investigations involved determining how much activation at specific sites in the brain was required to trigger artificial somatic sensations, relying on routine psychophysical procedures.

The EEG uses small electrodes placed at various points on the scalp that measure neuronal activity in the cortex, the outermost portion of the brain, which is associated with higher cognition.

They would affix the EEG electrodes to the participant's scalp, and would then instruct the subject to carry out some small, simple motor activity, such as pressing a button, or flexing a finger or wrist, within a certain time frame.

During the experiment, the subject would be asked to note the position of the dot on the oscilloscope timer when "he/she was first aware of the wish or urge to act" (control tests with Libet's equipment demonstrated a comfortable margin of error of only −50 milliseconds).

It was noted that brain activity involved in the initiation of the action, primarily centered in the secondary motor cortex, occurred, on average, approximately five hundred milliseconds before the trial ended with the pushing of the button.

That is to say, researchers recorded mounting brain activity related to the resultant action as many as three hundred milliseconds before subjects reported the first awareness of conscious will to act.

For instance, Susan Blackmore's interpretation is "that conscious experience takes some time to build up and is much too slow to be responsible for making things happen".

However, Max Velmans has argued: "Libet has shown that the experienced intention to perform an act is preceded by cerebral initiation.

"[15] In a study published in 2012, Aaron Schurger, Jacobo D. Sitt, and Stanislas Dehaene proposed that the occurrence of the readiness potentials observed in Libet-type experiments is stochastically occasioned by ongoing spontaneous subthreshold fluctuations in neural activity, rather than an unconscious goal-directed operation.

There is a small time delay due to the limited velocity of these many different signals that is indiscernible to people because it is extremely short.

[19]A more general criticism from a dualist-interactionist perspective has been raised by Alexander Batthyany[20] who points out that Libet asked his subjects to merely "let the urge [to move] appear on its own at any time without any pre-planning or concentration on when to act".

The contemporary philosopher Seyyed Jaaber Mousavirad argues that the Libet experiment is fully compatible with substance dualism.

[22] American philosopher, writer, and cognitive scientist Daniel Dennett argues that no clear conclusion about volition can be derived from Libet's experiment because of ambiguities in the timings of the different events involved.

Libet tells when the readiness potential occurs objectively, using electrodes, but relies on the subject reporting the position of the hand of a clock to determine when the conscious decision was made.

Libet's method presupposes, in short, that we can locate the intersection of two trajectories: so that these events occur side-by-side as it were in place where their simultaneity can be noted.

Libet's early theory, resting on study of stimuli and sensation,[25] was found bizarre by some commentators, including Patricia Churchland,[26] due to the apparent idea of backward causation.

Libet[27] argued that data suggested that we retrospectively "antedate" the beginning of a sensation to the moment of the primary neuronal response.

John Eccles[28] presented Libet's work as suggesting a backward step in time made by a non-physical mind.

They dispute an alternative explanation, suggested by Mackay in a discussion with Libet (1979, p. 219)[25] to the effect that 'the subjective referral backwards in time may be due to an illusory judgment made by the subject when he reports the timings', and more significant, Libet, et al. (1979, p. 220)[25] hint at 'serious though not insurmountable difficulties' for the identity theory (of mind and matter) caused by their data.Libet later concluded[30] that there appeared to be "no neural mechanism that could be viewed as directly mediating or accounting for" the subjective sensory referrals backward in time (emphasis Libet's).

We do not experience an infinite array of individual events but rather a unitary integrated consciousness, for example, with no gaps in spatial and colored images.

Thus the CMF is the entity in which unified subjective experience is present and provides the causal ability to affect or alter some neuronal functions.

Detailed description of the proposed experimental test is as follows: A small slab of sensory cortex (subserving any modality) is neuronally isolated but kept viable by making all the cortical cuts subpially.

[35] Robert W. Doty, professor of Neurobiology and Anatomy at the University of Rochester:[36] Benjamin Libet's discoveries are of extraordinary interest.

Libet's work is unique, and speaks to questions asked by all humankind.Susan J. Blackmore, visiting lecturer at the University of the West of England, Bristol:[37] Many philosophers and scientists have argued that free will is an illusion.

Unlike all of them, Benjamin Libet found a way to test it.Libet and his research into the delay is referenced several times in song titles by musical artist the Caretaker, who was influenced by some of his work.