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Unconscious is smarter than conscious
Environmental dependency in visuomotor responses

Abstract
We may tend to think that human understand current states of self-body and external environments, and thenconsciously control our limbs according to those states. However, dominant part of actual skilled movements arecontrolled unconsciously. We are trying to reveal those implicit sensorimotor control mechanisms to understandthe brain processing for skillful motor control. By inflicting different postural stability and/or noisy visual motion
conditions, we investigated the adaptability of voluntary and reflexive responses to visual motion stimuli, andfound that only reflex responses can be adjusted suitably to the different situations. This suggests that
unconscious processing would be smarter than conscious processing for a particular condition. By understandthe mechanisms of brain processing for sensorimotor control, we will be able to designe more sophisticatedcommunication and man-machine interface, and novel training method for athletes.

Body and arm movement control

Implicit and explicit sensorimotor processes

 In daily life, human has various physicalinteractions with external environments while
his/her body is moving, which cannot beeasily realized by current industrial robots.

It is generally considered that How can we realize these dexterous
interactions by using the brain information
processing whose transmission speed ismuch slower than that in current computers?

processing.

implicit process for sensorimotor
control is faster but is less flexible
than the explicit and voluntary
Conscious processing
Unconscious processing

The current study revealed that an implicit process canregulate sensorimotor response according to a particularenvironmental situation whereas an explicit process cannot [1].

Experiment: Context dependency of implicit and explicit processes for visual motion
ExperimentSupply environmental context of postural fluctuation
and/or random visual motion.

環境の文脈

Context-dependent
responses

Measure reflexive and voluntary visuomotor response.
1.Reflexive response （Manual Following Response：MFR）
2.Voluntary response （Motion Direction Discrimination）

Results
1.Reflexive：Context dependent and rational modulation
2.Voluntary：Context independent modulation

These results suggest that reflex mechanisms
properly connect the relationship between posturalstability context and visual motion while voluntary
motor system cannot.

Schematic diagram ofcontext dependent
implicit motor response

Unstable posture context ⇒ large MFR
Movable environment context ⇒ small MFR

References[1] N. Abekawa, H. Gomi, “Modulation difference in visuomotor responses in implicit and explicit motor tasks depending on postural stability,” Proc.
The Society for Neuroscience 47th Annual Meeting, 2017.
[2] H. Gomi, K. Kadota, N. Abekawa, “Dynamic reaching adjustment during continuous body perturbation is markedly improved by visual motion,”
Proc. The Society for Neuroscience 40th Annual Meeting, 2010.

Contact
Hiroaki Gomi Email: cs-openhouse-ml@hco.ntt.co.jp
Sensory and Motor Research Group, Human and Information Science Laboratory
オープンハウス 2020