Lauren R. Alpert The Graduate Center, CUNY Southern Society for - - PowerPoint PPT Presentation

Lauren R. Alpert

The Graduate Center, CUNY

Southern Society for Philosophy & Psychology

March 10th, 2016

variance in human embodiment

• ccurs along many

dimensions, including:

2 ¡

• height
• weight
• proportionality
• symmetry
• muscularity
• flexibility
• range of motion
• strength
• endurance
• etc.

photography: Howard Schatz, Athlete

…but tends to be in discussions about

Let ( ) refer to the claim that

Lawrence Shapiro

• J. Kevin O’Regan Alva Noë

Liam Dempsey Itay Shani

3 ¡

Theorists committed to this claim

• ften underspecify

,

• r in other words,

.

(the exact nature of this ‘contribution’ – e.g., constitutive or modulatory – is orthogonal to my present concerns)

Andy Clark has criticized expressions of EP Clark worries that

4 ¡

which are “

• f bodily form and dynamics,” implying that:

(especially O’Regan and Noë’s sensorimotor theory, 2001)

even that ensues.”

(2008c; my italics)

,

¡

EP conflicts with the :

He urges that

¡ until we have good reason to believe that phenomenal states cannot be multiply realized in subtly different bodies.

To avoid Clark’s worry,

One option is to treat ¡

5 ¡

between physical details that contribute to our phenomenology, and details that are too trivial;

– ? I will argue that .

It suggests that we can neglect the This implies that (e.g., legs, wings, or fins?) . ¡ as the markers of . ¡

:

6 ¡

1) defend the plausibility of the I will:

Ø explain what we can take for granted about kinesthesia Ø appeal to theories of motor learning & control Ø argue that (more likely than not)

. 2) explain Focusing on kinesthesia indicates that:

, without allowing that every bodily detail contributes to the realization of mental states.

=def qualitative experience of one’s body movement & posture

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embedded in muscles, tendons, joints, and skin :

¡

Plays an important in by supplying sensory feedback used to refine motor commands.

• the magnitude of

muscle contraction and relaxation,

• the intensity of

stretches in tendons and skin,

• the degree of change

in the angle of skeletal joints.

The are

• for short, changes in

.

changes in the mechanical properties

• f body parts,

in response to motor commands (in active movement)

• r external forces

(in passive movement)

Neurophysiologists currently favor a complex account

• f kinesthesia, on which:

8 ¡

Wolpert and Ghamarani (2000), fig. 3

Sensory prediction error

“ from muscle, joint, and skin receptors, as well as related to motor command, all ”

(Taylor 2013)

– effort – force – speed – tension – fluidity – balance – stability

differs from our , in that:

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whereas the stimuli for are to one subject’s body (and thus

).

stimuli for are to any particular body (and thereby

),

– not any one else’s, nor a generic, unspecified human form.

Consider two agents (A and B) with performing the .

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In other words,

A B (both backbending), (A’s body backbending vs. B’s body backbending)?

*stipulation: tokens of the same state type = phenomenal states that would be indiscriminable if both experienced & compared by one subject.

To assess whether their kinesthetic states are type-identical (i.e., sensationA = sensationB),

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For kinesthetic phenomenology, stimuliA = stimuliB is equivalent to movement mechanicsA = mechanicsB. we would have to investigate not only: whether they undergo equivalent processes

• f sensory transduction

(stimuliA è sensationA = stimuliB è sensationB ), but also: whether they are transducing equivalent stimuli in their respective bodies

(stimuliA = stimuliB).

So, do movement mechanicsA = mechanicsB?

12 ¡

environment ¡ task ¡ body ¡

de Rugy et al. (2013)

Let’s consult .

Both dynamical systems and computational models of motor control emphasize that

In short, these models converge in positing

A ,

which emerge from the interaction of its structural properties with nonspecific effects of the environment,

are called .

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Bodies differing in intrinsic dynamics develop particularized, “individually appropriate solutions” for motor coordination. (Thelen et al. 1993) This suggests that ≠ , whenever structural differences between A’s and B’s bodies yield differences in intrinsic dynamics. In other words:

I want to claim that:

14 ¡

One could defend this conditional as follows:

¡ A difference in A’s movement mechanics at two timepoints ( )

likely produces a discriminable

difference in kinesthetic sensation ( ≠ ). When the same mechanical difference occurs between A & B ( ≠ ), it likely produces a discriminable difference in kinesthetic sensation ( ≠ ).

…but the possibility remains that

,

even though ≠

.

15 ¡

Clark argues that ,

¡

If such compensatory processing takes place, then it’s that

This would be the case if kinesthetic sensations are by various sets of mechanical inputs. due to “compensatory differences in key aspects of downstream [neural] processing”. (2008b)

¡

at least .

¡

But

for interpersonal bodily differences in the realization of kinesthetic states?

16 ¡

It’s unclear what purpose it would serve us to have our kinesthetic sensations normalized to correct for body diversity. It’s also not apparent why it would be detrimental for us to have ,

the uniqueness of which mirrors the uniqueness of our bodies.

After all, the is the . It makes more sense for kinesthetic sensations to be than for body diversity to fail to produce interpersonal kinesthetic diversity.

By modus ponens,

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So, I stand by:

. 2. If , then .

…which is a qualified version of the

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Intrinsic dynamics could likely be by bodies of individuals sharing structural features at a macro level of description,

but varying at microscopic levels of detail.

Thus, my claim that avoids Clark’s slippery slope worry:

that if every physical difference produces a difference in phenomenology, embodied phenomenology conflicts with multiple realizability. ¡

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If one wants to claim that “the nature of one’s experience profoundly reflects the details of one’s embodiment” (Dempsey and Shani 2013), ¡ Dempsey and Shani state it would be to assert that: ¡ ¡ Instead, their account emphasizes that we ought to expect members of to . ¡

e.g., dogs, bats, humans, et al. are , which .

20 ¡

HUMAN phenomenology DOG phenomenology

realizes realizes

are an

Intraspecies body variance can be enormous, and its potential phenomenal impact is neglected on this approach.

21 ¡

The is an ,

about which bodily differences, at what level of physical description, make phenomenal differences. – at least for the kinesthetic modality of experience.

By ,

• ur view of the embodied mind will come closer to encompassing the

intricacies of our lived experiences moving through the world.

• Clark, A. (2008b) Pressing the flesh: A tension in the study of the embodied,

embedded mind? Philosophy and Phenomenological Research, 76(1), 37-59.

• Clark, A. (2008c) Supersizing the Mind: Embodiment, Action, and Cognitive
• Extension. New York: Oxford U Press.
• Dempsey, L.P., and Shani, I. (2013) Stressing the flesh: In defense of a strong

embodied cognition. Philosophy and Phenomenological Research, 86(3), 590-617.

• de Rugy, A., Loeb, G.E., and Carroll, T.J. (2013) Are muscle synergies useful for

neural control? Frontiers in Computational Neuroscience 7(19).

• de Vignemont, F., & Haggard, P. (2008). Action observation and execution:

What is shared? Social Neuroscience 3(3-4): 421-433.

• Latash, M.L. (2008) Synergy. New York: Oxford U. Press.
• O’Regan, J.K., and Noë, A. (2001) A sensorimotor account of vision and visual
• consciousness. Behavioral and Brain Sciences, 24, 939-1031.
• Schatz, H. (2002) Athlete. New York: HarperCollins.
• Thelen, E., Corbetta, D., Kamm, K., Spencer, J. P., Schneider, K., & Zernicke,
• R. F. (1993). The transition to reaching: Mapping intention and intrinsic
• dynamics. Child Development, 64(4), 1058-1098.
• Wolpert, D.M., and Ghahramani, Z. (2000) Computational principles of

movement neuroscience. Nature Neuroscience 3, 1212-1217.

lauren.r.alpert @gmail.com

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