For those want to learn more here is a thread I have prepared:
bsky.app/profile/rani...

To learn more about other findings, implications etc. read our preprint: doi.org/10.31234/osf...

We’d love to hear your thoughts, questions, or feedback! 💬

When execution remains demanding, it depletes supervisory resources needed to override prepotent responses → habitual responding emerges.
(17/X)

Our findings suggest that when execution automatizes, it may form modular “chunks” that goal-directed systems can flexibly deploy or withhold.
(16/X)

These two kinds of automaticity can be “dissociated” (you can tell there are two, not one) and they are even OPPOSING, across individuals.
(15/X)

What is going on? We think there are two distinct kinds of automaticity:
· Execution automaticity (efficient and regular motor action)
· Selection automaticity (stimulus-driven choice bypasses goal evaluation, and exercises habits even when they’re not rewarding)
(14/X)

After SHORT training: execution is disrupted (a non-habit goal-directed system “loses battle” but leaves a signature)
After EXTENSIVE training: execution stays smooth (habit fully consolidated)
(13/X)

ADDITIONAL FINDING - A window into habit consolidation:
We measured motor automaticity DURING habitual errors (after outcome devaluation).
(12/X)

· Different tasks & labs
· Different action modalities
· Different reward types
· Different reinforcement schedules
· Different training durations

ALL these data and variations showed the same inverse automaticity-habit relationship!
(11/X)

CROSS-PARADIGM GENERALIZATION:
We quantified a similar automaticity measure for (single action) free-operant tasks and tested 3 independent datasets (N=614) spanning:
(10/X)

PREREGISTERED CONFIRMATORY STUDY (N=258):
To test robustness, we preregistered (committed to our analysis in advance) a new, larger sample to test for the inverse relationship between motor automaticity and habit expression.
It replicated! Same effect. Same effect size.
(9/X)

BUT: Motor automaticity (inter-press-interval consistency of action sequences) inversely predicted habit expression.
Higher automaticity = LESS habit, regardless of training duration (short and extensive are similar).
(8/X)

DISCOVERY STUDY (N=193 subjects):
We compared two training lengths (short vs. extensive).
Extensive training → increased habitual responding ✓
This simple effect is actually not easy to show in humans. It validates that the new paradigm is showing a solid baseline effect.
(7/X)

The task was designed to:
1. Successfully induce rather quickly habits (that’s not easy - it’s a longstanding challenge in the field).
2. Jointly capture motor automaticity and habit formation.

Interactive demo: ranigera.github.io/DTH_pptdemo/ (open on computer)

(6/X)

How we discovered this:
We started by designing a novel dual-task paradigm that burdens cognitive mechanisms dedicated to planning and goal-processing at the moment of action.
(5/X)

We tested this assumption.
We found the opposite:
GREATER motor automaticity by the end of training showed REDUCED habit expression - the more automatically-responding people responded more to reward changes (i.e., less habitually).
This was a big surprise.
(4/X)

Repeated practice produces both motor automaticity (stereotyped execution with consistent timing) and inflexible habitual responding (the same actions are chosen even when they are no longer rewarding). These are commonly assumed to reflect a unified automaticity process.
(3/X)

spanning diverse action types, reinforcement schedules, and training contexts.

TLDR: They’re inversely related. Motor automaticity OPPOSES habit formation.
(2/X)