Motivation, Volition, Control

Three closely related concepts

(Follow-up to Hedonism Revisited and What “Matters”?)

To my current thinking, motivation, volition, and control are closely related but not quite identical things.

Motivation is what drives action.

You are motivated to do something, or you have an urge to do it, or a desire to do it, or an intention to do it, or an inclination to do it, or a drive to do it. Motivation is a relationship you have to an action.

You can also be motivated to resist, refrain from, inhibit, suppress, an action.

You can have conflicting motivations.

You can have subconscious motivations.

You can be motivated to do something without being (explicitly) aware you’re even doing it.

You can “find yourself” doing something while you weren’t paying attention; that’s still motivated.

Volition is the thing we experience as “on purpose” or “intentional.”

There’s a perceivable difference between:

• seeing and looking

• hearing and listening

• feeling and touching

and an analogous difference between “noticing” and “paying attention” in general.

Seeing, hearing, and feeling involve spontaneously noticing a sensation; looking, listening, and touching involve seeking the sensation, or paying attention to it, or concentrating on it.

There’s a common quality of “pressure” or “force” associated with looking/listening/touching, as compared with seeing/hearing/feeling.

It might actually come down to exerting muscular pressure or force in some cases — when you look, you move your eye muscles; when you touch something, you bring a part of your body into contact with it.

But listening doesn’t obviously seem to require a muscle movement, and neither does “concentrating” or “paying attention” in full generality. Volitional or intentional actions may sometimes only come with metaphorical “force” or “pressure.”

But nevertheless, there’s a clear subjective sense of what it feels like to “press”, to “try”, to “intend.”

When you “find yourself” doing something automatically, you are not using this kind of volition.

However, the situation where you “find yourself” doing something automatically is different from other kinds of “involuntary” actions:

• it’s not a reflex (which never reaches the brain)

• it’s not like digestion (which doesn’t even use voluntary/striated muscles and can’t be controlled at will)

• it’s not like tremor or chorea (which feel like the body “moving by itself” without your input)

When you “find yourself” acting on autopilot, your action is still controlled by your brain, and it still “feels like you” doing it. You’re just not doing a particular thing with your attention or “inner posture” that makes up the feeling of intention or “on purpose” or “trying.”

Almost all skeletal muscle movements by healthy awake people are, I think, motivated; but probably most of them are not volitional in the sense of “feeling like they’re done deliberately.”

Control

Control is the subjective experience of having mastery or confidence that what you do will turn out as you intend.

You get sensory feedback on every motion. As you move your head, your visual and auditory fields change accordingly. As you move any part of your body, you feel sensations of pressure or effort, you can touch whatever you come into contact with, and you can see changes in your body position.

Control is a relative phenomenon. The better you are at predicting the effects of your own movements, the more “in control” you feel. It’s a sense of “grip”. The feeling in your fingers of playing a piece of music you’ve mastered is a satisfying sense of knowing where everything is, having everything you need in reach, having a good sense of what you’re doing.

Conversely, feeling “out of control” would include things like losing your balance, wobbling or shaking, feeling overstimulated or overwhelmed, being shocked or startled, etc.

If you’re narrowly focused on one thing (like writing on a computer as I’m doing now), you have “control” over a few degrees of freedom — a small focused field of view, your typing fingers, your “inner voice” simulating speech. Over that small domain, you have a lot of control.

If, however, you’d be startled to hear a sound, or if you’ve totally forgotten about the rest of your body, you don’t have a lot of control over those other “channels” of sensorimotor information.

Control feels good.

Babies practice walking and grasping and other motor skills because it’s intrinsically satisfying to “get the hang of” things.

People (and animals) naturally seek out activities that give them a greater sense of control. This is pretty clearly what’s going on with stereotypies (or stims). Animals and people under conditions of stress or intense concentration, engage in repetitive motions, which can have a calming or “centering” effect. A feed of sensory stimulation under one’s own predictable control is inherently satisfying.

It may be that “self-stimulation” is only obvious as such when it’s repetitive and restricted. Someone moving flexibly and skillfully through a wide range of configurations, such as shifting their weight, walking, stretching, looking around, etc, is also producing a predictable and controlled stream of sensorimotor data.

Control is a quality or property of action. You have tighter control when you’re more capable of acting as you intend and getting the results you expect; you have something like “richer” or “more flexible” control when you have denser and higher-dimensional streams of sensorimotor feedback.

I think control can be relevant both to movements that feel “on purpose” and movements that you “find yourself” making when you weren’t paying attention.

The Readiness Potential and Volition

The famous “Libet experiment¹” asked subjects to choose to move at any time they want, and to recall the position of a revolving spot at the moment they made the decision to move. The “readiness potential”, a slow rise in voltage detectable on the EEG, precedes the action by about 550 ms; the self-reported conscious decision to move only happened at 200-150 ms before the motion.

The Libet experiment has popularly been taken as a “proof that free will doesn’t exist”, because the brain is “preparing to move” before we are even aware of making a choice to move.

But Libet himself never interpreted his experiment as a proof of the nonexistence of free will. And in fact a later experiment he conducted points to the contrary.

When subjects were asked² to wait for a visual signal and then move their hands, a “readiness potential” detectable with the EEG arises about half a second before their hand actually moves. If they're also asked to "veto" the movement just prior to moving, they also display the "readiness potential" about 500 ms before the 0 time, but it suddenly shifts direction at 200-150 ms.

This means that the actual difference between brain activity between people who choose to move and people who choose not to move happens, not at the onset of the readiness potential, but later, at the same time that the subjective “decision to move” happens.

The readiness potential might represent something else. Perhaps, it coincides with the “idea” of moving, the “hypothesis” that one might move. A possibility, which you can subsequently either follow through on or shut down.

Or, the readiness potential might just be a random spontaneous fluctuation in neuronal activity, as Aaron Schurger argued.³

Schurger also replicated the same phenomenon that Libet himself did — when you compare subjects asked to move spontaneously with subjects who don’t move at all, the brain activity of the two groups only diverges significantly 150 ms before movement, not the 500 ms before that would be expected if the readiness potential represented the decision to move.⁴

The readiness potential, in fact, correlates quite strongly with respiratory phase. People asked to move “whenever they choose” are more likely to move during an exhale than an inhale, even though they don’t know they’re doing this. Readiness potentials, likewise, are bigger during exhales than inhales. But people who are asked to move as soon as they see a green dot don’t have any correlation between motor timing and respiratory phase.

This suggests that, when we are free to move “whenever”, with no particular reason to choose one moment over another, fluctuating patterns of unrelated neural activity, including those caused by interoceptive sensations such as breathing, serve as “tie-breakers” that suggest a moment to act.⁵

These hypotheses aren’t incompatible with the idea of the readiness potential as a “hypothetical” or “simulated” movement. Perhaps, random or interoceptive fluctuations in neural activity prompt the “should I move now?” possibility; subsequently, you can either move, or not move.

The “ghost movement” that, with effort, you can perceive even when you stop yourself from moving, is clearly not your final decision to move. It might coincide with the readiness potential.

1. Libet, Benjamin. "Unconscious cerebral initiative and the role of conscious will in voluntary action." Behavioral and brain sciences 8.4 (1985): 529-539.

2. Libet, Benjamin, Elwood W. Wright Jr, and Curtis A. Gleason. "Preparation-or intention-to-act, in relation to pre-event potentials recorded at the vertex." Electroencephalography and clinical Neurophysiology 56.4 (1983): 367-372.

3. Schurger, Aaron, Jacobo D. Sitt, and Stanislas Dehaene. "An accumulator model for spontaneous neural activity prior to self-initiated movement." Proceedings of the National Academy of Sciences 109.42 (2012): E2904-E2913.

4. Uithol, Sebo, and Aaron Schurger. "Reckoning the moment of reckoning in spontaneous voluntary movement." Proceedings of the National Academy of Sciences 113.4 (2016): 817-819.

5. Park, Hyeong-Dong, et al. "Breathing is coupled with voluntary action and the cortical readiness potential." Nature communications 11.1 (2020): 289.