As shown on their BP/RP diagram, the rise in the readiness potential was clearly visible at about 550 milliseconds before the flex of the wrist (blue arrow).

The neurobiologist John Eccles had speculated that the subject must become conscious of the intention to act before the onset of this readiness potential.

The neurologist Benjamin Libet decided to test Eccles's idea. He performed a sequence of remarkable experiments in the early 1980's that were enthusiastically, if mistakenly, adopted by determinists and compatibilists to show that human free will does not exist.

Libet found that although conscious awareness of the decision preceded the subject's finger motion by only 200 milliseconds, the rise in the Type II readiness potential was clearly visible at about 550 milliseconds before the flex of the wrist. The subject showed unconscious activity to flex about 350 milliseconds before reporting conscious awareness of the decision to flex (the red arrow above). Indeed an earlier slow and very slight rise in the readiness potential can be seen as early as 1.5 seconds before the action.

This earlier rise is a Type I RP/BP, as explained in a personal communication from Lüder Deecke.

When you are saying: “Indeed an earlier slow and very slight rise in the readiness potential can be seen as early as 1.5 sec before the action.” this is indeed so. This is the BP1, the bilaterally-symmetrical early BP/RP component generated by both SMAs. The SMA is on the mesial surface of the hemisphere, behind it is the M1/Area 4 of the lower extremity leg and foot. So both SMAs are contributing to BP 1, and this is so even with unilateral movements. This is why we named the potential readiness potential, because this makes the brain ready for the intended movement or action.

And we later found the full explanation, I mean why this is so important, so early, and so necessary. Hans Kornhuber and I postulated that there has to be a CMA as well, and made sure there is. CMA means cingulate motor area, and the cingulate gyrus (cingulum is belt) you can look it up on brain maps. This is our emotional brain. It is like a belt running from anterior to posterior on the inner surface of the hemispheres around the corpus callosum (black). I labelled SMA and CMA into Karl Kleist’s brain map, which unfortunately is only available in German.

The book has a wonderful historical review of the concept of free will, including its twists and turns when twentieth-century behaviorists denied the existence of the mind, which had been the centerpiece of nineteenth-century psychology.

The Preface is well worth reading closely.

Why is it so important that this book appears in English and, what is more, is published in the United States? There are many reasons, here are three of them:

(1) To tell the full Bereitschaftspotential story. This slow brain potential, which precedes all our voluntary movements and actions, was discovered by the authors (Kornhuber and Deecke, 1964, 1965). We offered the translated term “readiness potential” in our publication, but the “tongue twister” Bereitschaftspotential (BP) was preferred. The Bereitschaftspotential can be found in the list of German words in the English language. It had quite an impact; it revived the opinion about will and volition and also about freedom as opposed to total determinism.

(2) A further discovery is that we have shown experimentally that the frontal lobes are initiating and steering a movement or particular task we perform. But the frontal lobe does not execute the task. It delegates the execution of the task to the expert systems in the brain, mostly to the motor-cortex-basal- ganglia-loop, but in case of visually-guided tracking movements even to the visual cortex itself. The reader of the book will get at least an idea, a feeling, what the human frontal lobes are and what they are doing. As we expound in our book, there is one important statement: The frontal cortex is the seat of the will. This is by no means widely recognized, and the main route of argumentation—what happens when the frontal cortex is destroyed?—is almost forgotten. That is to say, it is essential to incorporate the numerous classical lesion studies in our argumentation. By careful studies of frontal lesions in patients we can leam what the normal functions of the frontal cortex are. This is all classical heritage of Clinical Neurology. It was the discipline of Clinical Neurology that collected the largest body of experience about the abilities of man and his brain. This experience had led to two theories (models) of how the brain functions: (a) a hierarchical system of centers ordered side by side or on top of each other, and (b) a distributed system, in which, by nerve fibers, most of the brain is connected with many other centers, and this system achieves its performances always by distributed cooperation. The two models were heavily debated over decades. But this was on an either-or-basis: “Localisationists” fought against “network advocates.” As the reader will see in the book, we now teach that both principles are realized in higher brains.

(3) What then is will? As the present authors conceive it, will is a complex function, beginning with consideration, planning and thereafter, decision, all this taking place in the bright light of consciousness and with self-critical connection to reality, then shifting parts of the processing into unconscious routines but with accompanying supervision, surveillance, control and, if necessary, correction until the goal is reached.

We hope that our book may fall on fertile ground: There is a tradition also in the United States, where a movement against total determinism began, promoted by Edward Deci, Frederick Kanfer and others, which revived the tradition of William James, and also by Wayne Hershberger 1989. Deci and Kanfer’s key words are self-regulation, self-determinism and even self-management, terms implying free will. In philosophy too, a new discussion on the will and its freedom began. A book written by Sir Karl Popper and Sir John Eccles discussed the Bereitschaftspotential and Kornhuber’s ideas, and in the “Oxford Handbook of Free Will” the discovery of the Bereitschaftspotential is also discussed (Kane 2002). In the United States it is in particular the philosopher Daniel Dennett, who is writing important books and is an eminent promoter of will evolving in freedom.

The reader will find all this in the present book “The Will and its Brain,” he also may consult its index. In the end, he or she may agree with the authors in saying that it is extremely necessary to counteract the dogma of total determinism i. e. that we are totally determined in all our actions and doings. This would have the consequence that we are not responsible for what we are doing. Such an all too easy exculpation (“te absolvo"), some call it “self-corruption” is what people and the media may like to hear. However, it is not so. We do have freedom, inner freedom. Thus, we have responsibility for our deeds, and we can put a veto to bad intentions, e.g. when pursuing unethical goals.

The Will and Its Brain, p.xiii

But Lüder Deecke explains that early brain activity does not deny human freedom.

Decisions in the brain are mostly not made abruptly—except we are forced by the situation, for instance when skiing—rather they are made gradually. Even simple decisions—for instance the pressing of a right or a left button—need some time and a few seconds go by until we start the movement. The matter is different, if we are under time pressure or with rapt attention to a stimulus. This can be so because we were not yet absolutely determined or because the way from the frontal cortex does not go directly to motor cortex, which was earlier belief, but needs the cooperation of a phylogenetically old subcortical part of the brain that provides learned and stored movement programs, the basal ganglia. Functional magnetic resonance imaging then shows vague activities, which can be interpreted as if up to 10 s prior to the movement in the prefrontal brain a change in activity occurred that might lead to a decision a bit later, i.e., it looks as if an unconscious decision had been made [64]. This is not a sign of a lack of freedom, rather it signals insufficient attention or shortage of memory in conjunction with the absence of haste. The resulting movement is consciously controlled in any case.

Brain Sciences, 2012, 2, 414;