Neurocognitive free will is a process of generative self-construction

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Do human beings genuinely have free will?

Philosophers and theologians have wrestled with this question for centuries and have set out the ‘design features’ of free will – but how do our brains actually fulfil them?

A University of Warwick academic has answered this question for the first time in a new paper published today [31] in Proceedings of the Royal Society B.

Professor Thomas Hills from the Department of Psychology set out to bridge the gap between the philosophical arguments for free will and the neurocognitive realities.

In philosophy, elements of free will include the ability to do otherwise – the ‘principle of alternative possibilities’; the ability to deliberate; a sense of self; and the ability to maintain goals – ‘wanting what you want.”

Drawing on examples from making a morning coffee to taking a penalty kick, and considering organisms from human beings, e-coli, cockroaches, and even robots, Professor Hills argues that our neurocognitive abilities satisfy these requirements through:

  1. Adaptive access to unpredictability
  2. Tuning of this unpredictability to help us reach high-level goals
  3. Goal-directed deliberation via search over internal cognitive representations
  4. A role for conscious construction of the self in the generation and choice of alternatives.

Commenting on his paper, Professor Hills said: “Neurocognitive free will – the free will that we have as humans – is a process of generative self-construction.

I demonstrate that effortful consciousness samples from our experience in an adaptively exploratory fashion, allowing us to explore ourselves in the construction of alternative futures.

“There is evidence that people who believe in free will are more pro-social.

They adopt behaviour that benefits others and society as a whole, and have a greater sense of control of their future – they believe they can influence the future in positive ways. This is important.

Neurocognitive free will provides a basis for understanding why they are correct.

“Neurocognitive free will ties our understanding of free will to something real. It also helps us to understand what it means.

I suspect it’s not what most people think. As Sartre once said, “Freedom is not a triumph.”

But I think neurocognitive free will gives some hints to how it could be. That will be a focus of future work. “


Free Will: Definitions and Levels of Explanation

In most ages and cultures, free will has been considered a characteristic or capacity that human beings are generally endowed with and that has a special, if not unique, value (Van Inwagen, 1983). It was usually thought that the intrinsic freedom of individuals, distinct from the social and political one, was a prerequisite for dignity and moral responsibility (McKenna and Pereboom, 2016). Lay people generally think they have an intuitive idea of what free will is. However, scholars who have reflected on the topic from different perspectives have not agreed on a single definition of it, nor on necessary and sufficient conditions to exercise it. Moreover, philosophy has always raised the doubt that we might believe to be free even if we are not. Many thinkers, indeed, believe that the determinism we find in the physical world seems to be incompatible with freedom in the sense implied by free will.

Recently, science has brought new empirical evidence to support the thesis of the illusory nature of free will. And there is also a line of philosophical and political reflection that expresses skeptical optimism about free will (Pereboom, 20012013; Caruso, 20122013). According to these authors, the data at our disposal show that free will is an illusion, but this does not affect our lives (either individually or in society), because we can indeed do without the idea of free will and still defend ourselves against wrongdoers and reward the best individuals in the various fields of human activity, while reducing anger, resentment, and exasperated competition (Waller, 2011). However, there are reasons to doubt the groundedness of this perspective, whose undesirable consequences should not be underestimated (Lavazza, 2017a).

In this framework, which marks a break with respect to the past, the greatest challenge to realism about free will seems to come from epiphenomenalism. First of all, it might be useful to look at the terms under discussion, while stressing once again that there is no shared agreement on the definitions and, consequently, often philosophers and scientists end up talking about different things in the debate on free will. Once the scope has been circumscribed, we will see why epiphenomenalism is a greater challenge than classical determinism. Then, in the main part of the article, I will explain why not even epiphenomenalism seems able to bring decisive evidence to support the thesis that free will is an illusion.

In order to discuss the impact of epiphenomenalism on the idea of free will it is first necessary to define the key concepts. As mentioned, there is no universally shared definition of free will. According to a minimal definition, free will is “the variety of control distinctively required for agents to be morally responsible” (Vargas, 2011). Free will can also be more precisely defined by three conditions (cf. Walter, 2001). The first one is the ability to do otherwise. This is an intuitive concept: to be free, one has to have at least two alternatives or courses of action between which to choose. If one has an involuntary spasm of the mouth, for example, one is not in the position to choose whether to twist one’s mouth or not. The second condition is the control over one’s choices. The person who acts must be the same who decides what to do. To be granted free will, one must be the author of one’s choices, without the interference of people and of mechanisms outside of one’s reach. This is what we call agency, that is, being and feeling like the “owner” of one’s decisions and actions. The third condition is the responsiveness to reasons: a decision can’t be free if it is the effect of a random choice, but it must be rationally motivated. If I roll a dice to decide whom to marry, my choice cannot be said to be free, even though I will freely choose to say “I do.” On the contrary, if I choose to marry a specific person for their ideas and my deep love for them, then my decision will be free (Lavazza, 2016).

This is a very thick definition of free will, with very demanding conditions. It borders on the idea of Ultimate Authorship, which however captures all the traditional insights and reflections on freedom understood in the “metaphysical” sense. From here it is possible to restrict the scope of free will to a thinner definition, one that is also suitable for the scientific data emerging from the laboratories. In fact, the idea of free will could be summarized in, and circumscribed to, that of “conscious control” on one’s choices and decisions, where the qualification of “conscious” does not entail constant and relentless behavioral control but can also rely on habits or brain processes triggered at a time prior to the exercise of control. Even though this definition is unlikely to find general consensus, it could still be a good starting point.

Whatever idea of free will we may consider, physical determinism has always presented a particularly pressing challenge to it. Determinism—although many definitions of this concept have been proposed—can be taken to state that the initial conditions of the world and the laws of physics influence every single state of the universe at every subsequent instant, including therefore everything related to the human being as a physical entity. If determinism is true, human beings can be equated with pool balls, or with the victims of an evil surgeon who manipulates our brain states to produce our choices and our actions (Vihvelin, 2003/2017; Cashmore, 2010). Historically, an answer to this challenge has been offered by compatibilism, which affirms the existence of a certain type of free will in spite of determinism.

If compatibilists are happy with the choice being freely caused by one’s conscious desires (while desires might be determined by the law of physics), this response, which draws on a relevant and large philosophical tradition, has not always been considered satisfactory, except for pragmatic reasons. However, recent developments in the research on the interpretation of determinism and physical causation appear to reduce the scope of the determinist challenge. Ismael has, for example, made a convincing attempt at showing “how microlaws create the space for emergent systems with robust capabilities for self-governance,” arguing against the “threats to freedom that come from notions of causal necessity that physics has outgrown” (Ismael, 2016). The main idea is that “global laws do not imply strict necessity, nor do they impose a specific path on the universe given its initial conditions. This is because global laws have neither temporal asymmetry nor direction of influence. And the causal direction is given by modifying a variable in a subsystem that causes changes in another variable, within a framework in which there is a choice between exogenous and endogenous variables” (Lavazza, 2017b).

This does not mean that the challenge of determinism is outdated, but that today there are other threats to the traditional idea of free will that are more pressing and, apparently, more scientifically grounded, because they are not based on general laws but on the specific functioning of the mind/brain. Here we can distinguish—at least in general terms, because the levels are not clearly distinguishable—between the arguments that refer to metaphysical explanations and arguments that refer to epistemological explanations. If classic determinism if a genuine metaphysical claim, epiphenomenalism is related to psychological functioning of human beings and the interpretation of empirical data.

Epiphenomenalism is the thesis that seemingly causally relevant conscious processes, such as intention formation or decisions, do not play any active causal role in the production of the correspondent action. In general, the scientific arguments for epiphenomenalism start from the shared idea that free will implies a causal role of conscious mental processes. From this perspective, on the one hand, conscious mental processes should be explained in terms of scientific naturalism (which sets science as the sole measure of what exists and as the only method of knowledge) and this has turned out to be extremely difficult; on the other hand, in any case—most, if not all—our choices and decisions are taken to be guided by unconscious processes.

Following the useful clarification drawn by Nahmias (2014), even if it is objected that conscious mental processes can be naturalized as supervenient on underlying neuronal processes, the deflationary scientific perspective can answer the two following strategies. On the one hand, it can state, based on conceptual arguments, that the real causation is carried out by neuronal processes, and that conscious mental processes are only epiphenomenal. On the other hand, it can support, on the basis of empirical evidence, that the neuronal processes underlying conscious mental processes are not correctly “hooked” to the causal processes that bring about behavior, because, for example, they come too late (as in Libet’s experiments), or in the wrong place (as in Wegner’s experiments).

Nahmias calls the first scenario metaphysical epiphenomenalism. Like determinism and naturalism, it is relative to the form of causation; therefore, it is informed and affected only indirectly by the discoveries of cognitive sciences. In fact, all these theoretical positions are based on the general truth of knowledge about nature and of the brain in particular, but do not refer to single laws or explanations of cerebral functioning. Nahmias calls the second scenario modular epiphenomenalism. According to it, modules (a shorthand for somewhat encapsulated cognitive systems or processes) involved in conscious decisions or intention formation do not produce one’s behavior, which instead is produced by modules that do not involve conscious states.

I will address this second form of epiphenomenalism, trying to show that it is not a knock-out argument against free will. I will not address the challenge of metaphysical epiphenomenalism instead. Surely, this is a major challenge to free will in purely philosophical-conceptual terms. According to Kim’s exclusion argument (Kim, 1998), if our conscious mental states have no causal power, how can they guide our choices and our decisions based on a conscious reflection that answers to reasons? But upon closer inspection, one might maintain that not even the exclusion argument seems to have the final word on mental causation—let alone on free will (cf. Giorgi and Lavazza, 2018).

Since this article focuses in particular on the form of epiphenomenalism which implies that our choices are only consequences of external factors affecting our decision-making processes, it is useful to frame the rise of epiphenomenalism and its arguments both historically and conceptually. I will then try to show why both the empirical data and the arguments drawn therefrom do not seem sufficient to support the conclusion that our freedom is completely illusory.Go to:

Free Will and Empirical Psychology

In order to clarify and address the challenge of epiphenomenalism to free will, I’ll now very briefly retrace the history of the scientific research on the mind, from the perspective of the debate on free will. In my understanding, empirical psychology is part of the cognitive sciences (another view, for example, might take educational psychology to use empirical methods but not to be subsumable under cognitive sciences), which also include cognitive neuroscience. I will seek to highlight some core points that have led those who study free will to read the new experimental data as a basis to describe human behavior in terms of non-awareness and substantial automaticity. The premise is that the cognitive science studies conducted in the laboratory did not deal directly and specifically with free will, at least until Libet (Libet et al., 1983), and even after Libet they have mainly followed in his footsteps, so to speak (Saigle et al., 2018).

The basic assumption of classical cognitive sciences, of course, placed special emphasis on cognition, i.e., on all those conscious processes that contribute to making the agent aware of their environment and situation, evaluating their behavioral alternatives and deciding on the basis of intentions that may be the result of more general purposes, either given or consciously chosen at the time. This does not mean that classical cognitive sciences—with their representational-computational theory of mind—followed the general framework of intentional or folk psychology. Rather, they corrected the latter in many respects. Contemporary empirical psychology, which is fully part of the cognitive sciences, has helped to highlight how the so-called cognitive unconscious is not only an evolutively functional mode of action but also reflects an architecture of mind organized in modules with closed and automatic functioning. This acquisition has been inserted into more general views of the functioning of mind, for example the one elaborated by Fodor (19832001), which alongside modularity also claims there is a central top-down processing that presides over the central functions and, from the perspective that interests us here, over the most relevant choices for the agent.

Another relevant strand is that which describes our mental architecture, and its consequent functioning, as fundamentally bipartite (Kahneman, 2011). According to this view, there are two mental/cerebral systems that divide cognitive work and often operate in competition. One is quick and automatic—automatic precisely in order to be quick—and substantially unconscious. It allows us to manage environmental situations that require reaction speed according to established behavior patterns and is probably the result of an evolutionary-adaptive path. The other system is slower, fully conscious and the result of a processing that also considers new and more functional behavioral schemes to respond to the environment. It goes without saying that in this framework conscious control is ensured by the “slow system,” whereas when the “fast system” takes over, our choices and actions tend to lose the typical characteristics of free choices and actions.

More recently, the most important development in the field of so-called new cognitive sciences has been the replacement of the “computer metaphor” with the perspective of embodied cognition: a set of theoretical proposals (on a broad experimental basis) united by idea that most of higher cognitive processes occur through the control systems of the agent body (or, in neuroscientific terms, of the motor brain), with the related limits and potentialities (Shapiro, 2010). The dynamic and embodied models, in the most radical theories, give up the representations considered neither really existent nor useful to postulate from the heuristic points of view (Chemero, 2009), canceling the distinction between subject and environment and introducing a single dynamic system (Port and van Gelder, 1995).

In this sense, the brain is considered a dynamic system in which the activity of the different neuronal populations (more or less active over time) synchronizes on different frequency bands that can operate in parallel or enter into competition. It is argued that cognitive processes such as attention, preparation and facilitation arise from phase synchronization between different frequency bands or phase-resetting phenomena in some frequency bands based on specific stimuli (Caruana and Borghi, 2016). For example, this would explain the top-down control of non-hierarchical type: in this case the attentive processes are not explained by a hierarchical structure of upper and lower areas but in terms of local self-organized phenomena.

The various oscillatory frequencies give rise to transient states that each have a different response to a stimulus of the same type and intensity. When, for example, there is a motor behavior, the stimulus is processed differently according to the oscillatory phase of the brain in which it is received. Consider a go signal (like a traffic light): according to the phase of the alpha rhythm in which this signal arrives, the beginning of the movement and the reaction times vary. This indicates that motor behavior must be interpreted within a situation of changing equilibrium that reflects multiple dimensions of the internal situation of the brain immediately preceding it. It should be noted that these are intra-individual variations in response that are detectable in an instrumental way and do not determine a significant effect except in particular situations (the reaction time at the start of a professional sprinter may vary from race to race by thousandths of a second). In other words, this idea of the brain as a dynamic system—if confirmed—may enrich our knowledge but does not seem to directly affect our concept of free will in a deflationary sense. Rather, it appears to trace brain functioning back to schemes that are more compatible with our idea of free will, like Churchland and Suhler’s view of subcortical control (see section Dealing With Situationism).

What happens with motor behaviors also happens with sensory stimuli. When dealing with the borders of the human perception threshold, for example by administering a minimal electric current to the tip of a finger such that it is perceived at least in half of repeated administrations, the perception capacity depends strongly on spontaneous increases of activation in particular rhythms of oscillation of some cerebral cortices (Buzsáki, 2006). This sensory input may or may not be perceived, therefore, based on the immediately preceding transient status of a large-scale cortical network. It can be concluded that the external stimulus cannot be considered the only initial condition to evoke an answer: there is always a relationship with, and a reference to, the history of the cerebral state. Each cerebral state depends on the previous one, which has in turn interacted with external stimuli, in a dynamic chain which, however, seems to show certain consistency and continuity in the eyes of an external observer. This seems to mean that there is not a purely stochastic outcome of internal processes, but a repertoire that is built over time and which is drawn from every time.

In relation to embodied cognition, an interesting aspect is that of affordances, namely the dynamic relationships that are established between an agent and a perceived object, i.e., the opportunities for interaction with the physical entity that the subject deems achievable based on his own abilities and capacities (both physical and cognitive). Cisek (2007) proposed a model for the functioning of the motor system called “affordance competition hypothesis.” Our perceptive world generally manifests itself by offering us multiple possibilities for action. According to classical cognitive science, in a similar situation, first the brain selects the action to be performed and then plans how to do it in its motor details. Cisek’s hypothesis (based on experiments) says instead that the brain processes several potential actions in parallel. These action plans compete with each other to be realized, trying to inhibit one another (in a subpersonal process that does not involve higher circuits nor the subject’s awareness). In the end, albeit very quickly, various factors channeled to the prefrontal cortex lead to a decision in favor of a single action plan.

In relation to affordances are there real automatisms, as some pioneering studies in the area of embodied cognition seemed to show (Ellis and Tucker, 2000)? For example, on the basis of motor compatibility it seems that we are better and quicker at categorizing small objects if we have to press a small key and categorizing large objects if we have to press a large key, however we can consciously strive to improve our performances. But research in this field does not allow us to generalize these results. We are not driven by automatic processes related to unconscious body cognition, and the activation of affordances is modulated by goals and objectives through a top-down processing performed by the higher cognitive areas (Caruana and Borghi, 2016). Differences in categorization-performance with respect to congruence (small-small, big-big) exist and are a point in favor of embodied cognition, but they are not such as to question free will in areas that are relevant to the present discussion. This is because these phenomena only concern a part, though important, of our cognitive functioning, but not its totality.

On the other hand, there are experiments in which priming effects (behaviors triggered by clues or environmental elements, of which we are not aware at all or at least as causes of our behavior) or frail control effects seem to take over even in real life situations, restricting the scope of free will. For example, take a study that is often cited as an exemplary case of unconscious influence of the context on human behavior, which however encountered strong problems of replication (see section Dealing With Situationism). A group of American university students have been recruited for an unspecified psychological study. They were given a set of words with which to compose meaningful sentences, including numerous terms that, both in general and in American culture in particular, are related to stereotypes about the elderly, such as wrinkles, gray, Florida. Instead, a control group was given words containing neutral expressions with respect to age, such as thirsty, clean, private. At the end of the test, a monitoring system was set up in the corridor leading from the hall to the elevator: young people who had read and used the words connected to old age were walking more slowly compared to those who had read and used words unrelated to the later phase of life (Bargh et al., 1996). One may slow down one’s pace because one’s feet are sore or because one is trying to casually meet the cute person one saw come out of class the other day; however, it is bizarre to learn that one can walk slowly because one has just dealt with the words wrinkles and Florida. Therefore, it is reasonable to assume that our mind (or our brain) often, but not necessarily always, works and makes decisions by itself, without our conscious deliberation (in the sense of full awareness of a choice) (Wilson, 2004).


More information: Thomas T. Hills. Neurocognitive free will, Proceedings of the Royal Society B: Biological Sciences (2019). DOI: 10.1098/rspb.2019.0510

Journal information: Proceedings of the Royal Society B
Provided by University of Warwick

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