Investigating the empirical support for therapeutic targets proposed by the temporal experience of pleasure model in schizophrenia: A systematic review.
BACKGROUND
Anhedonia and amotivation are substantial predictors of poor functional outcomes in people with schizophrenia and often present a formidable barrier to returning to work or building relationships. The Temporal Experience of Pleasure Model proposes constructs which should be considered therapeutic targets for these symptoms in schizophrenia e.g. anticipatory pleasure, memory, executive functions, motivation and behaviours related to the activity. Recent reviews have highlighted the need for a clear evidence base to drive the development of targeted interventions.


OBJECTIVE
To review systematically the empirical evidence for each TEP model component and propose evidence-based therapeutic targets for anhedonia and amotivation in schizophrenia.


METHODS
Following PRISMA guidelines, PubMed and PsycInfo were searched using the terms "schizophrenia" and "anhedonia". Studies were included if they measured anhedonia and participants had a diagnosis of schizophrenia. The methodology, measures and main findings from each study were extracted and critically summarised for each TEP model construct.


RESULTS
80 independent studies were reviewed and executive functions, emotional memory and the translation of motivation into actions are highlighted as key deficits with a strong evidence base in people with schizophrenia. However, there are many relationships that are unclear because the empirical work is limited by over-general tasks and measures.


CONCLUSIONS
Promising methods for research which have more ecological validity include experience sampling and behavioural tasks assessing motivation. Specific adaptations to Cognitive Remediation Therapy, Cognitive Behavioural Therapy and the utilisation of mobile technology to enhance representations and emotional memory are recommended for future development.
Department of Psychology, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, UK. Electronic address: clementine.edwards@kcl.ac.uk.
Clementine J
CJ
Edwards
Department of Psychology, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, UK. Electronic address: matteo.cella@kcl.ac.uk.
Matteo
M
Cella
Department of Psychology, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, UK. Electronic address: nicktarrier228@gmail.com.
Nicholas
N
Tarrier
Department of Psychology, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, UK. Electronic address: til.wykes@kcl.ac.uk.
Til
T
Wykes
D003072:Cognition Disorders / Q000209:etiology; D016206:Databases, Bibliographic / Q000706:statistics & numerical data; D004644:Emotions; D056344:Executive Function; D006801:Humans; D008962:Models, Theoretical; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000150:complications / Q000628:therapy*; D012565:Schizophrenic Psychology
Anhedonia; Executive functions; Intervention; Negative symptoms; Schizophrenia; Systematic review