Abstract
Keywords
Cotard's syndrome is one of a cluster of seemingly bizarre, content-specific delusional syndromes which have been linked to brain injury and systemic neurological insult [1,2]. The focal delusional motifs in the most well known of these syndromes concern environmental or temporal repetitions and/or dislocations (reduplicative paramnesias), the misidentification of familiar others as malign simulacra (Capgras delusion, FréAgoli delusion, intermetamorphosis [3,4]) and various forms of transformation or dissolution of self-identity (Cotard delusion, reverse subjective doubles, lycanthropy). The most striking feature of Cotard's syndrome (le déAlire de néAgation [5]) is a sense of estrangement from ordinary reality so profound it leads delusional subjects to believe that they are dead or ‘undead’; that their bodies have disintegrated, putrefied or decomposed; and sometimes that they and the world around them have been catapulted into a parallel spectral reality, hell or Gehenna [1–7].
Although infrequently described in the English language literature, recent attempts to understand delusional misidentification in terms of the breakdown of normal mechanisms of sensory processing, reality testing and self-monitoring have refocused attention on the phenomenology of Cotard's syndrome and its links with classical reduplicative misidentification syndromes [7–12], particularly Capgras syndrome [7,11,12]. The case to be described is of particular interest in this context because Cotard and Capgras delusions are copresent, and because the subject's preoccupation with nihilistic and persecutory ideas appeared secondary to nocturnal intensification of persistent feelings of strangeness, depersonalisation and derealisation.
Case report
RY is a 17-year-old man who was admitted to a metropolitan rehabilitation facility 4 weeks after sustaining an extremely severe traumatic brain injury. Glasgow Coma Scale score [13] on admission was 6, Functional Independence Measure score [14–15] was 18. He was non-responsive to command and fully dependent for all care needs. Initial computed tomography revealed haematomas in the right thalamus and left basal ganglia, bilateral ventricular haemorrhaging and a shearing injury to the pituitary stalk.
Twelve weeks postinjury RY was able to vocalise at single word level and participate minimally in self-care, he remained grossly disoriented, perseverative and distractible. Improvement over the next 16 weeks of inpatient rehabilitation was marked, with RY making significant gains in auditory comprehension, sustained attention, participation in activities of daily living and in the initiation and maintenance of day-to-day interactions. Despite these gains, he continued to display severe functional deficits across all cognitive domains, including prominent memory deficits, and significant impairments in assessed verbal gener-ativity, speed of information processing, mental flexibility and in meta-abilities related to self-monitoring and critical inferencing. RY was anosmic, and described his vision as blurred and distorted with ‘everything’ in his visual field appearing strangely ‘buckled’. Orthoptic review 4 months postinjury indicated right traumatic midriasis, partial right Illrd, IVth, and VIIth nerve palsies, and left nystagmus. An EEG 5 months postinjury showed a slight excess of background theta activity, but no evidence of focal, lateralising or paroxysmal features.
During initial recovery indications were noted of apparently delusional ideation superimposed on post-traumatic amnesia (PTA), and this aspect of RY's clinical presentation remained essentially unchanged with the subsequent resolution of PTA. In the early morning RY consistently appeared perplexed and fearful, and perseverated on themes related to death, dismemberment, torture and persecution. He was intermittently verbally hostile and repeatedly accused nursing staff of having murdered members of his family. Delusional ideation also included thematic elements characteristic of Capgras syndrome. He frequently became restless and agitated when interacting with his father (DY), and on a number of occasions minutely examined DY's face before accusing him of being a ‘criminal’ double who had taken his father's place.
Clinical psychological and psychiatric evaluation found regular fluctuations in RY's experience of intense depersonalisation and accompanying nihilistic delusions. If interviewed in the morning or immediately after waking RY described all aspects of his physical and interpersonal environment as ‘not real’, and conspicuously incorporated impossible and horrifying dream events into delusional narrative. He also perseveratively repeated that he was dead and detained in Hell against his wishes. At all other times, however, he presented as mildly euphoric (fatuous and sexually disinhibited) with no obvious elements of dysphoria or fearful apprehension. RY's positively toned affective presentation and relative lucidity (except following sleep) were noted as inconsistent with the presence of simple delirium or of a depressive disorder with psychotic or melancholic features. There was no evidence of auditory command or formal visual hallucinations. It was concluded that RY's nihilistic delusions were secondary to extreme feelings of depersonalisation themselves maintained by his experience of exceptionally vivid dreams and nightmares which he was unable to effectively differentiate or partition from ordinary reality. Depersonalisation was most intense at night and then progressively subsided as RY became immersed in ordinary daily activities and social interaction. Interestingly, he at all times remained guarded and vigilant in interactions with his father and appeared never fully to accept DY's authenticity.
In view of the persistence of RY's delusional ideation he was commenced on 5 mg olanzapine nocte. Review after 10 days revealed a leveling of mood fluctuations, disappearance of dysphoria and restless apprehension, and apparently complete resolution of delusional ideation. At interview RY was able to discuss the prominent themes of his persecutory and nihilistic delusions without ‘sticking’ (becoming trapped in perseverative elaborations), and he reported the lifting of his sense that ‘everything in this place was fake’ 8 days after the commencement of antipsychotic medication. Again, despite the lifting of overtly psychotic ideation, he was still somewhat mistrustful of his father and (realistically) described his interactions with him as ‘confusing’ and ‘not really natural’.
Following stabilisation on olanzapine, RY was discharged to a regional brain injury unit for further rehabilitation. On discharge his mood was euthymic with no evidence of unusual ideas. His discharge Function Independence Measure score was 57 (Motor Sub-scale = 42; Cognitive Sub-scale =15).
Antipsychotic medication was subsequently progressively withdrawn without any re-emergence of dys-phoria or delusional ideation.
Discussion
Multilevel organic deficits may interweave with less-obvious psychological factors to create contentspecific delusions. RY displayed visual impairment, intense dysphoria, abnormal feelings and depersonalisation and/or derealisation as identified in Ellis and Young's ‘anomalous experience’ account of Cotard and Capgras phenomena [7,8,12]. This model conceptualises two syndromes as related attempts to counter feelings of unreality by providing a context for incongruous perceptual information. It suggests both delusions involve anomalous perceptual experience contributing to depersonalisation, and that this coupled with impaired self-monitoring and critical inferencing leads to misinterpretations of reality. The distinction between the syndromes is described as arising because, in Capgras delusion, subjects mistake ‘a change in themselves for a change in others (“they are imposters”)’, while in Cotard delusion, ‘people who are depressed exaggerate the negative effects of the same change whilst correctly attributing it to themselves (“I am dead”)’ [12, p.345].
RY's experience of nihilistic delusions only following the disorientating effects of hypervivid dreaming fits with this framework which emphasises depersonalisation and derealisation. (It is worth noting that dreams following multiple trauma characteristically revolve around imprisonment, punishment and ‘living death’ [16]). It is less consistent with the model's representation of severe depression as a correlate of Cotard delusion. The diurnal cycling in mood and affect in RY suggest that nihilistic delusions and major depressive disorder may be disarticulated by cognitive impairments. RY's inability to encode and recall his delusional experience precluded development of the pervasive depressed mood otherwise found in Cotard delusion. During the day, rapid forgetting of delusional experience and the ordinariness of RY's activities and interactions seemed to allow him to re-establish his sense of connection with reality, although during each subsequent night these connections were disrupted by darkness, relative isolation and intense dream imagery.
The stability of RY's belief that his father was an imposter suggests operation of a maintaining mechanism not clearly evident in his recurrent belief he was dead and imprisoned in hell. Contemporary neuropsychological accounts of delusional misidentification attribute Capgras phenomena to impaired face processing which disrupts the brain's ability to attach emotional significance to familiar faces [7–12]. This representation of Capgras syndrome as a kind of ‘mirror image’ of prosopagnosia [7], however, does not account for the complexity and selectivity of individual instances of Capgras delusion without acknowledgement of the significance of symbolic representations [17]. Prior to brain injury RY's relationship with his father was reported as ambivalent. His subsequent preoccupation with his son's recovery appears to have contrasted too starkly with RY's memories of their relationship to be accepted as authentic. Overlaid with perceptual and metaprocessing deficits, RY's inability to reconcile past and present internal representations seems to have led to the psychodynamically meaningful [18,19] negation of both his father's expressed feelings and his sense of relationship with RY.