Cognitive Adaptation

Summary

A hallmark of our survival in the real world and of our capacity to navigate the complex social interactions of human society is our ability to show behavioral adaptation. Adaptation can be necessary for a number of reasons, making the study of the process challenging. Two classes of event can signal a need for adaptation: 1) Events caused by one's own actions and specifically FeedBack -FB- from those actions (e.g. the investigators adapt their strategy after an erroneous choice), and 2) Events not linked to our actions, specifically Action-InDependent Events -AiDE- (e.g. the investigators adapt their strategy after a change of rule). These two types of information - FB and AiDE - will frequently occur concurrently. A critical and difficult part of adapting appropriately involves resolving the difference between the two. So for example an incorrect FB can occur because the investigators made an error, or because something unexpected in the environment has changed -the rule switched, someone cheated, etc. The Investigators must work out which it is, as they will frequently require different behavioral adaptations. Their task is made even more complex by the fact that the dynamics of evidence accumulation after FB vs AiDE are very different. FB has a direct temporal and causal link to an executed action, which means that the investigators are certain to derive information about a given action from a given FB. In contrast, AiDE have no such contiguity and no initial relation to actions, which means that the investigators must accumulate evidence to identify the appropriate adaptation to an AiDE. So the crucial dilemma is this: after an unwanted outcome, should the investigators adapt as if they made an error and received a negative FB, or should they continue to accumulate evidence as if there has been an AiDE to which they need to know how to adapt. Animals are able to resolve this credit assignment problem, as evidenced by their ability to appropriately adapt their behavior. A breakdown of this ability to link unexpected events to their correct cause would seem to be at the source of impairments in a wide range of psychological and neurological disorders, from addiction and OCD to psychological symptoms in Parkinson's disease. Yet the neural basis of this process is currently unknown, and FB and AiDE processing have been assessed separately so far. ADAPCO will provide unprecedented characterization of brain systems critically involved in learning from and adapting to FB, AiDE, and their interactions, thanks to fMRI studies.

Conditions

• Healthy

Interventions

OTHER

First session of fMRI: localization of the premotor areas of the medial frontal cortex

Subjects should perform simple tasks to map the premotor areas of the medial frontal cortex. In this context, they will have to perform hand, tongue, ocular movements for about 20s. Additionally, as part of a control condition, they will need to perform eye fixation on a cross shown at the center of the screen for about 20s.

OTHER

Second fMRI session

The subjects will position their left and right thumbs on response buttons. Each trial will begin with the appearance of one of 2 possible indexes. It will be an unknown abstract visual stimulus). After a variable delay of 0.5 to 6s (average = 2s), a blue or yellow circle will appear on the left or right of the screen.

OTHER

Third fMRI Session

This session is identical to the second session but the subject will have to respond by performing saccadic ocular responses.

OTHER

Training fMRI session

The training session will consist in training the subject to carry out the different behavioral tasks that he will then have to perform during the sessions of fMRI.

OTHER

Pilot behavioral study

In a pilot study, 30 subjects will participate in a behavioral study (2 sessions of 2 hours each) aimed at establishing the learning characteristics of the different types of rare events unrelated to actions (visual and sensorimotors on the hand).

OTHER

fMRI Study

Each subject will participate in 2 fMRI sessions of about 2 hours each: a first session in which a first version of the task will be presented and a second session in which the second version of the task will be presented.

Sponsors & Collaborators

• Hospices Civils de Lyon

  lead OTHER

Principal Investigators

• Philippe Domenech, MD · Henri Mondor University Hospital

Study Design

Allocation

NON_RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

20 Years

Max Age

45 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2015-09-24

Primary Completion

2022-08-24

Completion

2022-09-24

Countries

• France

Study Locations