title: Implicit and explicit processing of emotional facial expressions in Parkinson's disease.
abstract: OBJECTIVE
  Besides motor problems, Parkinson's disease (PD) is associated with detrimental emotional and cognitive functioning. Deficient explicit emotional processing has been observed, whilst patients also show impaired Theory of Mind (ToM) abilities. However, it is unclear whether this PD patients' ToM deficit is based on an inability to infer otherś emotional states or whether it is due to explicit emotional processing deficits. We investigated implicit and explicit emotional processing in PD with an affective priming paradigm in which we used pictures of human eyes for emotional primes and a lexical decision task (LDT) with emotional connoted words for target stimuli.
  
  
  METHODS
  Sixteen PD patients and sixteen matched healthy controls performed a LTD combined with an emotional priming paradigm providing emotional information through the facial eye region to assess implicit emotional processing. Second, participants explicitly evaluated the emotional status of eyes and words used in the implicit task.
  
  
  RESULTS
  Compared to controls implicit emotional processing abilities were generally preserved in PD with, however, considerable alterations for happiness and disgust processing. Furthermore, we observed a general impairment of patients for explicit evaluation of emotional stimuli, which was augmented for the rating of facial expressions.
  
  
  CONCLUSIONS
  This is the first study reporting results for affective priming with facial eye expressions in PD patients. Our findings indicate largely preserved implicit emotional processing, with a specific altered processing of disgust and happiness. Explicit emotional processing was considerably impaired for semantic and especially for facial stimulus material. Poor ToM abilities in PD patients might be based on deficient explicit emotional processing, with preserved ability to implicitly infer other people's feelings.
authors: Departments of Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University Magdeburg, Leipziger Str. 44, 39120 Magdeburg, Germany.
authors: Caroline
authors: C
authors: Wagenbreth
authors: Departments of Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University Magdeburg, Leipziger Str. 44, 39120 Magdeburg, Germany.
authors: Lena
authors: L
authors: Wattenberg
authors: Departments of Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University Magdeburg, Leipziger Str. 44, 39120 Magdeburg, Germany; Department of Behavioral Neurology, Leibniz Institute of Neurobiology, Leipziger Str. 44, 39120 Magdeburg, Germany.
authors: Hans-Jochen
authors: HJ
authors: Heinze
authors: Departments of Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University Magdeburg, Leipziger Str. 44, 39120 Magdeburg, Germany. Electronic address: tino.zaehle@ovgu.de.
authors: Tino
authors: T
authors: Zaehle
mesh_terms: D000328:Adult; D000339:Affect; D000368:Aged; D004644:Emotions; D005149:Facial Expression; D000066499:Facial Recognition; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000523:psychology*; D056345:Theory of Mind
keywords: Emotion; Facial expression; Parkinson’s disease; Priming; Theory of mind