Il est actuellement admis que les symptômes négatifs apparaissent précocement dans la maladie schizophrénique et seraient plus prédictifs du fonctionnement futur des patients que les symptômes positifs [16Brown R.G., Pluck G. Negative symptoms: the ‘pathology’ of motivation and goal-directed behaviour Trends Neurosci 2000 ;  23 (9) : 412-417 [cross-ref]

Cliccare qui per andare alla sezione Riferimenti]. L’apathie, symptôme transnosographique puisqu’on le retrouve dans un ensemble de maladies neurologiques [14Robert P., Onyike C.U., Leentjens A.F., e al. Proposed diagnostic criteria for apathy in Alzheimer’s disease and other neuropsychiatric disorders Eur Psychiatry 2009 ;  24 (2) : 98-104 [cross-ref]

Cliccare qui per andare alla sezione Riferimenti], fait partie des symptômes négatifs fréquemment rencontrés dans la schizophrénie et s’avère constituer un handicap majeur pour le rétablissement des individus qui en souffrent [19Hartman M., Steketee M.C., Silva S., e al. Working memory and schizophrenia: evidence for slowed encoding Schizophr Res 2003 ;  59 (2–3) : 99-113 [cross-ref]

Cliccare qui per andare alla sezione Riferimenti]. Cependant, si les traitements médicamenteux (neuroleptiques de première et seconde générations) ont fait la preuve de leur efficacité sur les symptômes positifs, ils n’ont montré que peu d’effets sur les symptômes négatifs et particulièrement dans l’apathie pouvant même parfois, du fait de leurs effets secondaires l’aggraver [40Heinz A., Knable M.B., Coppola R., e al. Psychomotor slowing, negative symptoms and dopamine receptor availability an IBZM SPAECT study in neuroleptic-treated and drug-free schizophrenic patients Schizophr Res 1998 ;  34 (1–2) : 121

Cliccare qui per andare alla sezione Riferimenti]. Longtemps considérée en clinique comme la perte de la volonté, des avancées récentes issues de la neuropsychologie cognitive et des données en neuro-imagerie ont abouti à des définitions plus strictes et des approches nécessairement multidimensionnelle de l’apathie. L’apathie peut actuellement se définir comme une réduction quantitative et donc observable de comportements volontaires orientés vers un ou plusieurs buts [13Levy R., Dubois B. Apathy and the functional anatomy of the prefrontal cortex-basal ganglia circuits Cereb Cortex 2006 ;  16 (7) : 916-928

Cliccare qui per andare alla sezione Riferimenti]. Néanmoins à notre connaissance, ces différents modèles n’ont jamais été mis à l’épreuve dans la maladie schizophrénique. Cet article a pour objectif de passer en revue les avancées scientifiques récentes portant sur l’apathie. Puis dans un second temps, d’explorer si les approches multidimensionnelles actuelles peuvent s’appliquer à la complexité psychopathologique décrite sous le terme d’apathie dans cette pathologie schizophrénique.

Schizophrenia is a chronic and severe mental illness that affects over 1% of the population, characterized by multiple symptom dimensions. One of this class of symptoms, “negative symptoms”, have received more attention over the last few years. Negative symptoms, including among others blunted affect, withdrawal or apathy, are particularly important for recovery and are associated with negative functional outcomes, such as inability to get an employment and conduct normal daily living activities. While positive symptoms are usually treated by antipsychotic drugs, negative symptoms are usually persistent, which indicates the need for better treatment. The aim of this article is to highlight recent scientific progress on apathy and to explore current multidimensional approaches of this concept in schizophrenia. Apathy is a symptom frequently encountered in schizophrenia and in many neurological disorders. Therefore, it can be regarded as a transnosographic symptom.

A long time considered as a loss of motivation (psychological concept hard to define), recent descriptive and etiological models have proposed to consider apathy as a multidimensional phenomenon. Marin et al., have proposed a model of apathy in reference to the motivation concept. Marin et al.’s apathy model is composed of three dimensions: firstly, cognitive dimension, secondly, sensory-motor dimension and thirdly, affective dimension. These authors propose to differentiate “apathy syndrome” from “apathy symptom”. “Apathy syndrome” resulting from a lack of motivation whereas “apathy symptom” results from cognitive and/or emotional/affective disorders. In addition, Marin et al. propose that apathy syndrome corresponds to the “lack of motivation” not attributable to diminished level of consciousness, cognitive impairment or emotional distress. Following this proposal, Levy and Dubois propose to define apathy as a quantitative reduction of self-generated, voluntary and purposeful behaviors. It is therefore observable and can be quantified. Levy and Dubois have proposed an apathy model considering: firstly, apathy as a syndrome related to reduction in goal-directed behaviors; secondly, anatomically, apathy can be secondary to dysfunctions or lesions of the prefrontal cortex. Since the prefrontal cortex is functionally and anatomically heterogeneous, subtypes of apathy occur in diseases affecting the basal ganglia, because these diseases disrupt associative and limbic pathways from/to the prefrontal cortex; thirdly, from a pathophysiological point of view, apathy may be explained by the impact of lesions or dysfunctions of the basal ganglia, because these lesions or dysfunctions lead to a loss of temporal and spatial focalization, both of which result in a diminished extraction of the relevant signal within the frontal cortex, thereby inhibiting the capacity of the frontal cortex to select, initiate, maintain and shift programs of action.