Thread by @AnneEUrai

Choice history biases subsequent evidence accumulation
My latest with @jwdegee, @k_tsetsos and @donner_lab now out in @eLife!

paper: doi.org/10.7554/eLife.…
blog: tinyurl.com/y4g3rqa3
code: github.com/anne-urai/2019…
data: doi.org/10.6084/m9.fig…
story:👇

Ever noticed how your behavior is affected by the choices you've made in the past - even when you *know* it's better to just focus on the information in front of you?

You're not alone! Across many different experiments and tasks, people show choice history biases.

These biases vary between individuals - some people tend to repeat, others consistently switch from their previous decisions.

But *how* do previous choices affect the dynamics of a decision, from seeing a stimulus to reporting what you saw?

We can use a powerful model of decision-making, the DDM, to answer this question. The trick: using choice patterns plus RT distributions, we can disentangle if history biases arises from a shift in starting point or in drift bias, i.e. the rate of evidence accumulation.

We re-analysed 6 existing datasets from a range of different perceptual decision-making tasks. In all of them, individual differences in repetitive behavior were explained by history-dependent changes in the drift bias of the accumulation process.

This was true irrespective of the outcome (correct/error) of the previous choice, lasts several trials, and is most likely due to an asymmetric input to populations of accumulators that encode different choice options.

Using multiple datasets, and fitting different kinds of sequential sampling models really helped in showing the robustness of these findings. #openscience ftw ✨

Excitingly, this gives us a starting point for finding neurophysiological correlates of this biasing process. Next question: how does the brain integrate information about previous choices into a new decision as it unfolds?🧠

Want to hear more? I'll be talking about this work at #rldm2019, Wednesday July 20th @ 1pm in the workshop organized by @valentinwyart and @RafaPolania. If you're in Montréal, come say hi!

sites.google.com/view/vldm-work…

Correction pointed out by @k_tsetsos: the workshop is on the 10th. Too excited to carefully check my calendar, apparently