Depersonalisation Flashcards
learning objectives
- to recognise the features of depersonalisation/ derealisation
- to understand the possible neurophysiological bases for emotional numbing and its relationship to DP/DR
- be familiar with the functional neuroimaging research in DP/DR and the role of the vento-medial prefrontal cortex
- to realise what cognitive functions are preserved and what may be impaired in DP/DR
- to understand the basis of self awareness in terms of cognitive, emotional and interoceptive inputs
- the action of lamotrigine and potential benefits in patients with DP
- the theoretical basis for rTMS as a possible treatment for DP/DR
what is the dsm v definition for dissociative disorders - depersonalisation-derealisation syndrome?
persistent experience of feelings of detachment, either bodily or cognitively from themselves or from their environment
what are the core clinical qualifiers for dissociative disorders?
intact reality testing
significant distress or impairment
does not occur exclusively during the course of another disorder
wide spectrum affecting emotional, cognitive and physiological functioning
which situations does depersonalisation often occur?
life threatening danger
what is the causal model of depersonalisation?
DPD results from a normally protective neural response to high levels of arousal which becomes persistent and dysfunctional
prevalence of dpd is particularly high in which group of patients?
panic disorder patients
what is the mean age of onset in dpd
22.8 years
what is the gender preponderance for dpd
dpd occurs in 55% of males
which factors have been found to worsen depersonalisation symptoms?
psychological stress
environmental lighting
physical stressors e.g. fatigue
neurophsiological basis
Sierra et al. (2002) autonomic response in depersonalisation disorder
- skin condutance between patients with cDPD, controls and anxiety disorder
- recorded response to non specific elicitors and emotionally valent pictures
- **skin conductance to unpleasant pictures was significantly reduced in cDPD patients **
- latency of response significantly increased in cDPD group
- response to non specific stimuli was quicker than controls suggesting a heightened alertness
- emotional numbing
neurophysiological basis
stanton et al. (2001) basal activity of the hypothalamic-pituitary-adrenal axis in patients with depersonalization disorder
- salivary cortisol levels measured in patients with DPD, MDD, and healthy controls
- BDI scores significantly higher in DPD patients than controls but MDD higher than both
- basal cortisol levels significantly lower in DPD patients compared to MDD but not controls
- therefore reduced basal activity of the HPA axis in depersonalisation disorder
neurophysiological basis: method
Owens et al. (2015) Abnormal cardiovascular sympathetic and parasympathetic responses to
physical and emotional stimuli in depersonalization disorder.
- BDI, DEI, CDS
- heart rate and blood pressure measured during supine, 3 min sustained hand grip, 3 min cold pressor, 5 min upwards head tilt
- heart rate, blood pressure, heart rate variability recorded during 5 min upwards head tilt and continuous presentation of unpleasant images
- heart rate and blood pressure orienting responses to simultanous head tilt and pseudorandom valent images
DEI: dissociative experiences scale; CDS: cambridge depersonalisation scale
neurophysiological basis: results
Owens et al. (2015) Abnormal cardiovascular sympathetic and parasympathetic responses to
physical and emotional stimuli in depersonalization disorder.
- suppressed sympathoexcitation in depersonalisation shown by increased heart rate to cold pressor, decreased high freq heart rate variability and increased diastolic blood pressure to unpleasant picturers
- cardiovasular autonomic dysregulation in depersonalisation disorder centrally mediated
functional imaging
Phillips et al. (2001) depersonalisation disorder: thinking without feeling
neural responses to emotionally salient stimuli between depersonalisation pts, ocd pts and healthy controls
images rates for emotional content
control groups rates aversive images as more emotive than dpd patients
control groups showed greater activation in the insula and occipito-temporal cortex than dpd patients
activation in the right ventral prefrontal cortex in depersonalisation patients
insula only activated towards neutral stimuli in dp patients
absent subjective experiences of emotion are associated with a reduced neural response in emotion sensitive regions
which brain regions are associated with emotion sensitvity to disgust in depersonalisation
insula and occipito-temporal cortex
which brain region is associated with emotion regulation in depersonalisation
right ventral prefrontal cortex
functional imaging
Lemche et al. (2007) Limbic and prefrontal responses to facial emotion expressions in depersonalization
- event related fMRI recorded simultaneously with skin conductance
- neutral, mild and intense happy and sad facial expressions
- only patients showed decreases in subcortical limbic activity to increasingly intense happy and sad facial expressions
- only patients showed a negative correlation between skin conductance and bilateral dorsal prefrontal cortices for happy and sad faces
- abnormal decrease in limbic acitvity and increase in dorsal prefrontal cortices may underlie emotional detachment in dpd
functional imaging
Tabibnia et al. (2008) The Sunny Side of Fairness: Preference for Fairness Activates Reward Circuitry (and Disregarding Unfairness Activates Self-Control Circuitry)
- self reported happiness and neural responses to fair and unfair offers controlling for monetary pay off
- compared to unfair offers of equal monetary value fair offers increased happiness rating activation in the ventral striatum, amygdala, vmpfc, ofc and midbrain
- accepting unfair offers associated with activation in right ventrolateral prefrontal cortex (emotion regulation)
- accepting unfair offers associated with decreased activation of the anterior insula (negative affect)
ofc: orbitofrontal cortex
sierra et al. (2014) A structural MRI study of cortical thickness in depersonalisation disorder
- region of interest and vertex-based methods
- significantly lower cortical thickness in the right middle temporal region
- vertex methods showed differences in cortical thickness in bilateral temporal lobes, inferior frontal regions, right posterior cingulate
- vertex methods showed increased thickness in right gyrus rectus and left precuneus
- clinical severity scores are negatively correlated with cortical thickness in the middle and right inferior frontal regions
- grey matter changes in frontal temporal and parietal lobes are associated with depersonalisation disorder
- does not tell us if this signifies vulnerability or disease marker **
cognitive measures
which cognitive functions are preserved/ impaired in depersonalisation
- Empathy performance is unimpaired despite subjective deficits
- Show normal effects of overt emotion on memory (words and pictures)
- Less sensitive to negative facial expressions of emotion
what are the three parts of the cognitive-affective-somatic view of the self
- continuous sense of ongoing events
- congruent somatic response
- appraisal of emotional colour and valence
a brain model of depersonalisation involves which three components
- sense of the self
- ventrolateral prefrontal cortex
- insula
what are three treatments for depersonalisation
lamotrigine
rTMS
biofeedback
