Does - PowerPoint Presentation

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Does impaired metacognition contribute to schizophrenic delusions ? Joëlle Proust

Metarepresentation and metacognition workshopUniversity of OsloApril 29, 2014

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OutlineIntroduction: Cases of delusionsImpaired Metarepresentational ability (Frith 1992)Impaired simulation (Daprati et al, 1997, Jeannerod and Pacherie, 2004)Impaired metacognitive control and monitoring Impaired metacognition

Conclusion: remediation?Slide3

DelusionsA delusion is « a  belief held with strong conviction despite superior evidence to the contrary »This definition is faulty for taking a delusion to be merely a belief

; it may often consist in a global change in one’s experience of the worldThe inflexibility of delusions

distinguishes them from (truth sensitive) belief states.

Alternative definition:  «a set of persistent bizarre or irrational beliefs that are not easily understood in terms of an individual’s social or cultural background ».Some delusions are not caused by a mental illness, but rather by high fever, poisoning, drugs, hemiplegia etc.Slide4

Cases of delusionDelusion of control of one’s actionsDelusion of referenceThought insertion, thought withdrawal, thought broadcastingPersecutory delusionFregoli delusionErotomaniaCotard

syndromGrandiose & religious delusionsProprioceptive delusionCapgras delusionSlide5

Cases of delusionDelusion of control of one’s actionsThought insertion, thought withdrawal, thought broadcastingPersecutory delusionDelusion of reference

Fregoli delusionErotomaniaCotard syndromGrandiose & religious delusionsProprioceptive delusion

Capgras delusionSlide6

Delusions of controlSome patients with schizophrenia, as well as brain-lesioned patients with alien hand syndrome, present a dissociation between the feeling that their own body is moving – an experience of ownership related to the fact that something is happening to the self, the feeling that their body is being moved by a foreign intention, rather than of the subject’s own will – a perturbed feeling of agency. Slide7

4 intriguing featuresAsymmetry between SO and SA: no case of an impression of agency without an impression of ownership, no symmetrical delusion.Comparable xenopathy in delusion of control and thought insertion.External attribution versus feeling of non-agencyOcasionality problem: why is agency

impaired in certain cases not others?Slide8

Hypothesis 1: metarepresentationA) The generation of intentions to act is massively impaired in patients: poverty of will, lack of persistence in their work, poor personal hygiene, difficulties communicating with others. B) Intention control and monitoring is also often impaired: patients have difficulties selecting an appropriate action-schemaC) Finally, patients with schizophrenia monitor their actions in an abnormal way. They are able to correct failed actions only if they have access to visual feedback, in contrast to normal subjects, who also rely on internal forms of monitoring.Slide9

The control of action: Shallice (1988)Two functional levelsthe contention scheduling system (CSS) activates effectors on the basis of environmental affordances and triggers routine actions. It is regulated by mutual inhibition ("winner takes all").the Supervisory Attentional System (SAS) is able to trigger non-routine actions, or actions that do not involve stimuli presently perceived. Slide10

The MR dimensionThe main feature of SAS that allows it to both provide an agent with conscious access to her actions and to control routine actions is a metarepresentational capacity.Frith (1992): If metarepresentation is malfunctioning, there will be an imbalance between higher-level conscious processes and lower-level unconscious processes. As a result, patients will be aware only of the contents of propositions, not of the metarepresentations in which they are embedded. Slide11

Frith 1992Having had metarepresentations in the past, they are still able to attempt to form them. But they end up grasping only the embedded content: When trying to form the thought that someone thinks about P, they might only think P Instead of considering some form of action/thought, they will mistake the representation of a possible action/thought for a command to act/think Slide12

Objection: overgeneralizationPatients don’t have trouble reporting their own mental states: they are « hyperreflexive » (Sass et al. 2001)They are not impaired in reading minds in contexts not involving action of the self.Does not explain attribution of own actions to others.Slide13

The motor control hypothesis: A faulty or irregular efference copy?When acting, a forward model of the action is activated by the command.A comparator cuts down the amount of feedback required to check whether the action is successful, and makes control of action in normal subjects smooth and quick. In schizophrenia, the comparator might be faulty, thus depriving the agent both of the capacity to anticipate the observed feedback and to consciously take responsibility for her actions and thoughts (Feinberg (1978).Frith & Done,1989, Malenka et al., 1982;

Mlakar, Jensterle,. & Frith, (1994), Wolpert

et al., (1995); Blakemore, Rees, & Frith, (1998).Slide14

Forward modelSensorydiscrepancy

Sensorimotor System

Motor

Command

Sensation

Efference

Copy

Predicted Sensory Feedback

(Corollary Discharge)

Predicto

r

Actual Sensory FeedbackSlide15

The motor control hypothesis: A faulty or irregular efference copy? Patient with delusion of control is aware of (i) her goal, (ii) her intention to move, (iii) her movement having occurred,But not of (iv) her having initiated her movement, because she failed to predict the sensory consequences of the movement..

Frith & Done,1989, Malenka et al., 1982; Mlakar, Jensterle,.

& Frith, (1994), Wolpert

et al., (1995); Blakemore, Rees, & Frith, (1998).Slide16

the motor control system makes use of internal models, including inverse and predictive models, and comparators. action-control mechanisms and action-awareness mechanisms are importantly connected. Matching feedback correlates with a sense of agency for the action.degree of mismatch between predicted and observed feedback modulates activation in the right inferior parietal lobule, and is responsible for external attributions of action. Slide17

the sense of extraneity result from a lack of sensory self-attenuation, itself caused by a failure to predict consequences of one’s own actions. (Blakemore et al., 2000: self-tickling & auditory hallucinations)the sense of passivity results from the absence of self-attenuationSlide18

QuestionHow does a mere difficulty in predicting the consequences of one’s actions generates, on top of a perturbed sense of agency, an attribution to others of one’s actions, even though the sense of ownership is not perturbed?Slide19

First attempt at addressing the problem: the simulation theorySlide20

Impaired simulationSimulation mechanisms are activated when observing as well as imagining and executing actions. Intentions to act are thus represented impersonally. Such impersonal intentions are labeled naked intentions. recognition of own/others’ agency depends on observed cues. Patients with schizophrenia have a general difficulty in simulating actions. Evidence from subjects with auditory hallucination suggests that they do not predict feedback from their own inner speech – another form of covert, simulatory activity. (Daprati et al, 1997, Jeannerod

& Pacherie, 2004)Slide21

Impaired simulation: a who system involvedThe motor system represents the actions of others to the same extent that it represents agent’s own. The phenomenology of alien control might result from impairments to the mechanisms controlling and/or monitoring the different modes of simulation involved in the ‘Who’ system.(Daprati et al, 1997, Jeannerod

& Pacherie, 2004, Pacherie et al 2006)Slide22

Impaired simulation2004 follow-up by Farrer et al. of Daprati et al.'s 1997 study shows that the level of activity in the patient’s right posterior parietal cortex fails to be proportional to the discordance between expected and observed feedback, as it is in control subjects.  A defective simulation mechanism, rather than a defective action monitoring mechanism, combined with a general disruption of the self-other distinction, could be responsible for an impaired sense of agency in patients with schizophrenia. (Daprati et al, 1997, Jeannerod

& Pacherie, 2004, Farrer et al. 2004)Slide23

ObjectionsIf generally impaired simulation underlies the patients’ deficits, why do they seem to plan their actions normally? why do patients with alien control delusions believe that particular agents are controlling their actions? Is self-identity affected by impaired self-attribution of actions, and how so? how does the view explain that attribution of action and thought are both impaired? Occasionality problem unsolveddelusion inflexibility not explainedSlide24

Second attempt at addressing the problem: the revised control theoryFletcher & Frith (2009)Slide25

Common mechanism hypothesisMax Coltheart (2007) has argued that an account of delusions must include an account of impaired perception, and an account of abnormal belief.Against a two-deficit account, F & F (2009): Theory

of coincidental damage unlikely Minimization of prediction error explains both the hallucinatory aspect (

abnormal perception) and the delusional aspect of perturbed SA in schizophrenia.Slide26

Abnormal connectivitySensory consequences of self-generated acts should normally elicit less brain activity than those of an externally generated act.This is not the case in Schizophrenia: there

is a poor connectivity between motor and sensory regions (fMRI by Mechelli et al. 2007)

Between rostral and caudal LPFC regions (Barbalat et al. 2011)  pb

in « binding different temporal features of information into a temporary, unitary and coherent representation within the episodic buffer »Fletcher & Frith (2009)Slide27

Koechlin Sommerfield2007linSlide28

Functional role of system hierarchyPrediction error emitted by a lower-level provides input for a higher-level system (« input not fully accounted for »)Feedback from the higher-level system is supposed to provide a readjustement to reduce the

prediction error (new beliefs and inferences)Motivate discounting the present modelReallocate attention: a violation of expectation

renders an occurrence more salient (Kapur 2003)

Fletcher & Frith (2009)Slide29

System hierarchy impaired in schizophreniaPrediction errors emitted by the lower- level system are false, hence cannot be solved at a higher-level Propagate higher up: delusional belief

that others control self, changed self-identity, etc.Slide30

System hierarchy impaired in schizophreniaPrediction errors emitted by the lower- level system are false, hence cannot be solved at a higher-level Propagate higher up: delusional belief

that others control self, changed self-identity, etc.Slide31

What is the contribution of Impaired metacognition to schizophrenic delusions?Slide32

Where does metacognition step in?When a prediction error is occurring, it does not need to be monitored by metacognition (specialized in monitoring cognitive actions)Acting, however

, normally elicits in humans, noetic feelings, i.e. predictions about what one can

remember, discriminate, understand, in brief: all the information that

can be exploited to achieve and further one’s goals. It seems that these feelings, in patients, tend to express either inflated or no confidence at allSlide33

Impaired metacognitionAn impaired metacognition can result From inappropriate monitoring – failing to have uncertainty feelings/ judgments matching the validity of the performanceFrom inappropriate control – failing to use monitoring to

make congruent control decisions.Slide34

Impaired metacognitionAn impaired metacognition can result From inappropriate monitoring – failing to have uncertainty feelings/ judgments matching the validity of the performance  Garety

From inappropriate control – failing to use monitoring to make congruent control decisions  KorenSlide35

Noetic feelingsHave generally been ignored as a component in the hierarchical control systemsNoetic feelings, however, are permanently monitoring the informational changes that our bodily actions generate as a side effect.You recognize a face or a place as familiar, you

find a sign as strange, a landscape as beautiful, an activity as boring.Slide36

From prediction error to metacognitionPhenomena such as enhancement of background sounds or sights that should be irrelevant can be explained by the prediction error being

inappropriately quantified through inappropriate higher-level top-down modulation.Stimuli with large prediction errors

will befelt as

strange and externally generatedSeen as demanding attentionMore readily associableFletcher and Frith 2009Slide37

Role of prediction error in noetic feelingsEnhanced sensory experiences are a source of noetic feelings, because they constitute in themselves « epistemic affordances »More salient  more fluentMore relevant  more motivating

for attention , thinking and planningMore readily associable  More informative

Fletcher and Frith 2009, Proust 2014Slide38

A powerful source of motivationClinical evidence suggests that patients are often very motivated by the metacognitive feelings elicited by their modified perceptions and by their potential new status as cognitive agents.Some of them even see

themselves as about to build up far-reaching theories about the universe, or about society, etc. this positively rewarding

feedback from noetic feelings might

participate in fixing the delusion. (Pessiglione et al. 2006)Slide39

Dichotomous confidence & monitoringIt is not the prediction errors per se that are faulty, but the way they are « quantified »: uncertainty about prediction error and about its significance are poorly estimated:Undue weight to

small prediction error + underestimation of uncertainty = false inferenceA large prediction error may

be rejected by being « diluted in excessive noise »

Fletcher and Frith 2009Slide40

Why dichotomous confidence ratings ?There are two ways of understanding dichotomous confidence ratings:Either as reflecting an impairment in monitoring one’s confidenceOr in reflecting an impairment in control sensitivitySlide41

dichotomous confidence & monitoringReasoning biases are generally understood from poor monitoringbelief inflexibility: Delusional beliefs are felt by patients as self-evident jumping to conclusions = restricted data gathering: dichotomous confidence rating (all or nothing): « extreme responses »

Garety et al. (2005), Slide42

dichotomous confidence: monitoring?Reasoning biases are generally understood from poor monitoringbelief inflexibility: Delusional beliefs are felt by patients as self-evident = might also be a problem of failing to revise a belief jumping to conclusions = restricted data gathering is a problem of control not monitoringdichotomous confidence rating (all or nothing): « 

extreme responses »: also possibly a matter of controlSlide43

Arguments in favor of a control problemBelief inflexibility: People able to report alternative explanations for their delusional beliefs are more likely to respond positively to the possibility of being mistaken (Freeman at al., 2004).Garety interprets as belonging to belief monitoring;reflecting on one’s own beliefs, changing them in the light of reflection and evidence,generating and considering alternatives”

Garety et al. (2005)Slide44

In Garety’s model, however, the crucial steps involve control …/Slide45

Garety et al. 2005: reasoning processes in delusion conviction and changeJTC= jumping to conclusionsER= extreme respondingPM= possibility of being

mistakenSlide46

Thinking style in delusions (Garety et al. 2005)Jumping to conclusions (on a probabilistic reasoning task) and more frequent endorsement of extreme responses independently conribute to belief inflexibility- misrecognition of possibility of being mistaken.

The jumping to conclusions bias is thought to reflect a data-gathering bias, specifically, the rapid acceptance of a proposition in the absence of much information (Garety & Freeman, 1999).consistent with the hypothesis that patients make less use of past information when forming judgments and are

overinfluenced by current stimuli at the expense of context or previous learning

Hemsley, 1988; Kapur, 2003).Slide47

Dichotomous ratings and controlAn alternative explanation is that patients, due to an executive difficulty in associating a decision to a particular context, fail to correctly translate their feeling of confidence with the corresponding decision to respond, in particular

when this response

is offered

verbally.Slide48

Impaired metacognitive control sensitivity30 patients with first episode of schizophrenia.Asked to perform a Wisconsin task sorting taskThen, asked to rate their level of confidence in the correctness of their performanceFinally, asked to choose whether they want this trial to be ‘‘counted’’ toward their overall performance score on the test. Koren et al., 2006Slide49

Koren et al. 2006Slide50

Koren et al.,2004Results: Insight into illness was correlated with correct confidence rating adequate control sensitivity. some patients, however, presented a dissociation between correct monitoring and inadequate control = failure in control sensitivity (correct subjective feedback, but not used in selecting action).Slide51

Proposal fo a systemhierarchyEXPLICIT AGENCY ATTRIBUTION

PERCEPTION, THOUGHT,ACTION EXEC LEVEL

CONTROL OF PERCEPTION,ACTION, THOUGHT

RATIONAL CONTROL OF PLAN SELECTION IN SELF

AND OTHERS

SENSE OF

ENDURING SELVES

METACOGNITIVE

MONITORING

SELF-IDENTITY

SENSE OF AGENCYSlide52

ConclusionThe most promising theory of the cognitive correlates of schizophrenia consists in showing the functional links betweena disturbance of frontal connectivity a disturbed anticipation of the consequences of the action a poor access to the

context of a task/action.Irrelevant saliences seen as carrying important predictive valueSlide53

ConclusionThis theory should be completed by an analysis of how preserved metacognitive feelings and impaired control sensitivity feedback into the executive hierarchy at the various levels identifiedAre a source of repeated and failed

attempts at re-establishing coherence in predictions and sensings.Slide54

To reduce delusion inflexibility, patients should be encouraged to redirect their metacognitive monitoring on topics that do not encourage ascent in the hierarchyReporting

others’ testimony of their

own delusional

themes before they provide their own report is an important implicit cue that they can use. (Henri

Grivois’s clinical method)Metacognitive training

useful for elevating control sensitivitySlide55

The endYour questions and critiques are welcome !