Illusion of Command: How Indiana University Research Challenges the Traditional Neuroscience of Decision-Making

For decades, the human experience of making a choice has been characterized by a neat, intuitive progression: we perceive our surroundings, deliberate on the information, and execute a physical action. This linear framework—frequently dubbed the "sandwich model" by cognitive scientists—has long anchored both everyday introspection and advanced model-based cognitive neuroscience. However, a comprehensive new study published in the Journal of Cognitive Neuroscience by Indiana University professor Tom James suggests that this familiar sequence is fundamentally flawed. According to James’s paper, titled "Sensorimotor Mechanisms of Decisions and Actions," what humans experience as a conscious, centralized decision-making process may actually be an illusion generated by simultaneous, interacting physical systems within the brain, body, and environment.

The findings challenge foundational assumptions held across psychology, philosophy, and neuroscience, offering a radical shift in how researchers conceptualize human agency, volition, and behavioral output.

Challenging the Linear "Sandwich Model"

The traditional model of human behavior posits that sensory processing occupies the bottom layer of a cognitive sandwich, motor activity occupies the top layer, and a distinct, centralized cognitive stage sits squarely in the middle. Within this paradigm, the brain is thought to weigh options, form intentions, and transmit executive commands downward to the motor system.

James argues that while sensory mechanisms and motor mechanisms have clear, identifiable neural correlates, the supposed cognitive decision-making stage lacks any corresponding neural machinery. There is no isolated command center in the human brain that operates as a distinct chief executive, monitoring incoming data and issuing final edicts.

Instead, James contends that behavior emerges through continuous, concurrent loops of "action selection." These processes involve fluid, simultaneous interactions between the brain, the physical body, and the external world. Rather than moving in a strict linear sequence from sensation to cognition to action, these neural and physical operations loop back into one another dynamically, meaning that action and perception are inextricably bound rather than managed by a higher-level supervisor.

The Physicalist Framework: Decisions as Abstract Descriptions

To ground his hypothesis, James adopts a strict "physicalist" framework, drawing heavily upon the philosophical traditions of thinkers like Daniel Dennett. Physicalism asserts that physical phenomena can cause both physical and nonphysical outcomes, whereas nonphysical phenomena—such as abstract thoughts, desires, or purely mental decisions—cannot independently exert a physical force on the material world.

Because sensory inputs and motor outputs are undeniably physical processes, James argues that a purely mental decision cannot literally cause a physical action. To clarify this counterintuitive claim, James employs a series of robust analogies.

The first relies on Daniel Dennett’s classic comparison between the self and a center of mass (CoM), or center of gravity. A center of mass is an exceptionally useful mathematical abstraction; it allows physicists and engineers to calculate stability, trajectory, and balance with precision. However, a center of mass is not a physical object that can independently exert a force. One cannot physically manipulate an object’s center of mass without moving the object itself.

In the same vein, James proposes that a "decision" functions as an abstract, high-level description of behavior rather than a physical entity that triggers movement.

A second analogy examines institutional behavior. Society routinely uses shorthand phrases such as "the university decided to implement new campus policies." While this phrase is a convenient narrative tool for summarizing a complex web of events, saying that "the university" acted tells an observer very little about the actual physical mechanisms involved. A truly rigorous, granular explanation requires detailing specific physical events: committee meetings, administrative phone calls, security deployments, and document signings.

According to James, cognitive neuroscience faces a parallel problem. Labeling a sequence of events as a "decision" provides a useful macro-level summary of human behavior, but it fails to reveal the micro-level physical mechanisms operating inside the neural tissue. As James maintains, mental phenomena are frequently defined at a level of abstraction that is too high for the mechanistic goals of empirical neuroscience.

The Wall-Following Robot and the Cartesian Theater

To demonstrate how complex, goal-directed behavior can manifest without any centralized control system, James points to a classic cybernetic thought experiment: a simple mobile robot constructed with a minimal number of sensory and motor modules.

Configured to perform "wall-following" behavior, the machine can appear remarkably purposeful to an outside observer. As it navigates a complex room, hugging boundaries and avoiding obstacles, it projects an aura of intent, strategy, and deliberation. Yet, the robot possesses no central processing unit dedicated to decision-making.

"The robot does not have decisions built into it," James explains. "It just senses its environment and moves around accordingly. And based on the environment, wall-following turns out to be a good thing. It looks intentional. It looks strategic. It looks like the robot is making decisions. And yet, it is not. The reason we know it is not is that there are no systems built into it to do that."

This observation exposes a profound question for human biology: if a rudimentary machine can generate behavior that appears driven by conscious intent without housing an internal decision-maker, why must scientists assume that humans require a central controller?

Furthermore, invoking a central controller creates an intractable philosophical dilemma first highlighted by philosopher René Descartes. If a higher-level entity inside the brain is tasked with observing sensory data and deciding upon a course of action, science is immediately forced to explain how that internal controller operates.

"Explaining that the brain works by way of a central controller suggests that you haven’t figured out how the brain works, because you’ve just put a person inside your brain," James notes, referencing Daniel Dennett’s critique of the "Cartesian Theater." If a miniature person inside the brain makes decisions, that miniature person would logically require another controller inside its own brain, leading to an infinite regress that solves nothing.

Methodological Implications and Future Research

The shift from a centralized command model to a distributed, sensorimotor interaction model carries sweeping implications for the future of cognitive neuroscience. For decades, experimental designs have relied heavily on linear paradigms, isolating distinct moments of perception, deliberation, and motor response within laboratory settings.

If James’s physicalist and embodied approach gains traction, researchers will need to develop entirely new experimental frameworks capable of capturing continuous, non-linear complexity. This includes studying how neural, somatic, and environmental variables interact simultaneously in real-time.

Laboratories specializing in embodied cognition and ecological psychology are already beginning to pioneer these dynamic methodologies. By moving away from the assumption that the brain functions like a traditional computer running discrete decision algorithms, scientists may unlock more accurate models not only of human agency, but of a wide array of cognitive and mental phenomena that have long resisted reductionist explanations.

Ultimately, James’s work does not suggest that human choice is an illusion in the colloquial sense—people still weigh options, plan futures, and experience the heavy burden of deliberation. Rather, it redefines what those choices actually are: exceptionally useful, high-level narratives that describe the complex, beautifully orchestrated physical symphony of the brain, body, and world acting as one.