Maria Giannakou

Relationship of affect recognition with psychopathology and cognitive performance in schizophrenia.

The purpose of the present study was to explore the relationship between emotion perception and both psychopathology and cognitive functioning in a group of Greek patients with schizophrenia. Thirty-five patients with schizophrenia were assessed with computerized tests of emotion perception, using visual faces (Kinneys Affect Matching Test, KAMT), prosody (Affective Prosody Test, APT), and visual everyday scenarios (Fanties Cartoon Test, FCT), as well as a facial recognition test (Kinneys Identity Matching Test, KIMT). The patients were also evaluated with the symptoms dimensions derived from the PANSS (positive, negative, cognitive, depression, and excitement) and a battery of neuropsychological tests measuring executive functions, attention, working memory, verbal and visual memory, visuospatial ability, and visual scanning/psychomotor speed. The three emotion perception and face recognition tests correlated significantly with each other. The KAMT was significantly related to the cognitive symptoms dimension of the PANSS and executive functions. The FCT was significantly related to level of education and attention. Finally, the APT was significantly related to the cognitive symptoms dimension, executive functions, and attention. Our findings regarding the significant relationships of affect perception, both facial and vocal, as well as in everyday scenarios, with several cognitive abilities support the notion that deficits in decoding affective information in schizophrenia could be attributed to impairment in more basic neurocognitive domains.

Studying social cognition in patients with schizophrenia and patients with frontotemporal dementia: theory of mind and the perception of sarcasm.

We investigated social cognition and theory of mind in patients with schizophrenia and in patients with frontotemporal dementia in order to elucidate the cognitive mechanisms involved in the breakdown of these skills in psychiatric and neurological patients. Our tasks included videotaped scenarios of social interactions depicting sincere, sarcastic and paradoxical remarks, as well as lies. We found impaired performance of the schizophrenia group on all theory of mind conditions despite their intact understanding of sincere statements. In contrast, the FTD group performed poorly only when they had to rely on paralinguistic cues indicating sarcasm or lies, and not on paradoxical remarks or sarcasm when given additional verbal cues. Our findings suggest that, while current deficits in social and interpersonal functioning in patients with FTD may reflect a decrement in previously acquired skills, similar deficits in patients with schizophrenia may reflect an altogether inadequately learned process.

Impaired emotion perception in schizophrenia: A differential deficit

We investigated previously reported contradictory findings regarding the nature of deficits in emotion perception among patients with schizophrenia. Some studies have concluded that such deficits are due to a generalized impairment in visual processing of faces, while others have found it to be restricted to facial emotional expressions. We examined 37 patients and 32 healthy controls, matched on age and education, using three computerized tests: matching facial identity, matching facial emotional expressions, and discrimination of subtle differences in the valence of facial emotional expressions. Our results showed impaired matching of emotions in patients with schizophrenia. This impairment did not manifest on tasks that depended on perceiving the identity of faces or cues of the relative valence of facial emotional expressions. Our findings support the differential deficit hypothesis of emotion perception in schizophrenia.

Deficits in sustained attention in schizophrenia but not in bipolar disorder

The aim of the present study was to investigate sustained attention in remitted patients with bipolar disorder and in patients with schizophrenia, as compared to each other and to healthy controls; a secondary aim was to investigate the correlations of different symptom dimensions with performance on sustained attention in the two patient groups. Participants were 29 (18 men) outpatients with schizophrenia (SZ), 19 (8 men) patients with bipolar disorder I (BP) in remission, and 30 (15 men) healthy controls (HC); all three groups were matched on age, sex ratio, and level of education. Symptom severity (positive symptoms, negative symptoms, and general psychopathology) of patients with SZ were assessed with the Greek version of the Positive and Negative Syndrome Scale (PANSS); residual affective symptoms of patients with BP were assessed with the Young Mania Rating Scale (YMRS) and the Montgomery-Asberg Depression Rating Scale (MADRS). Sustained attention was measured by means of the Penn Continuous Performance Test (PCPT). The three groups differed significantly on the PCPT scores. Patients with SZ performed more poorly than both the BP and HC groups, whereas patients with BP did not differ significantly from HC. Performance on the PCPT did not correlate significantly with scores on the YMRS and MADRS in patients with BP. Also, scores on the PCPT did not correlate significantly with scores on any of the three subscales of the PANSS. Outpatients with schizophrenia presented deficits in sustained attention, whereas patients with bipolar disorder I in remission did not manifest such impairment. These results imply that impaired sustained attention might be a more enduring deficit in schizophrenia than it appears to be in bipolar disorder.

Sex differences in neuropsychological functioning among schizophrenia patients

Objectives: Evidence from the literature addressing sex differences in cognition in schizophrenia remains equivocal, with some researchers suggesting that male schizophrenia patients are more impaired than female subjects, while others report no significant sex differences in cognitive functioning. The aim of the present study was to investigate whether the differential pattern of cognitive performance observed in healthy men and women is preserved in male and female schizophrenia patients. Method: Ninety-six schizophrenia patients (56 men) were compared with 62 age- and gender-ratio matched healthy controls (31 men), on a battery of neuropsychological tests that assessed basic cognitive abilities: attention, working memory, abstraction, inhibition, fluency, verbal learning and memory, visual memory, visuospatial skills, and psychomotor speed. Results: As a group, schizophrenia patients were significantly impaired in each of the cognitive domains assessed, with the exception of psychomotor speed. The effect of sex was significant for verbal learning and memory, wherein women outperformed men. No significant group × sex interactions were found in any cognitive domains, indicating that the female advantage typically observed in verbal learning and memory remained the same in the schizophrenia patients. Conclusion: The degree of cognitive impairment is the same for male and female schizophrenia patients. Those sex differences found among the patients were typical of the healthy population as well. Therefore, differential decrements in basic cognitive domains do not appear to account for the favourable course of schizophrenia in women relative to men.

Humor appreciation deficit in schizophrenia: the relevance of basic neurocognitive functioning.

The purpose in undertaking the present study was to investigate humor appreciation in patients with schizophrenia. Moreover, we sought to explore the potential relationship of humor appreciation with measures of psychopathology and cognitive functioning among the patients. Thirty-six patients with schizophrenia were compared with 31 normal controls matched for age, sex, and education on a computerized test comprising captionless cartoons: Penn’s Humor Appreciation Test (PHAT). The patients were also evaluated on the symptom dimensions derived from the Positive and Negative Symptom Scale (positive symptoms, negative symptoms, cognitive symptoms, depression, and excitement), as well as a battery of neuropsychological tests measuring executive functions, attention, working memory, verbal and visual memory, visuospatial ability, and psychomotor speed. Patients with schizophrenia had significantly lower scores on the PHAT than normal controls. The patients’ performance on the PHAT correlated with scores on Penn’s Continuous Performance Test, the Stroop Color-Word Test, and the phonological subscale of the Greek Verbal Fluency Test. Our findings indicated impaired humor appreciation among patients with schizophrenia. The relationship found between the appreciation of captionless cartoons involved an incongruous detail and performance on a broad neuropsychological battery suggested that the deficit in humor appreciation in schizophrenia could be attributed to impairment in more basic neurocognitive domains, namely, selective and sustained attention as well as phonological word fluency.

Psychotic features associated with multiple sclerosis

Although once considered rare, several more recent investigations have been published describing psychotic features in multiple sclerosis (MS). The association between the two conditions, however, remains unclear. Large-scale hospital-based, epidemiological and case studies have suggested a relationship between psychosis and MS through demonstrating their higher than chance co-occurrence, their temporal relationship, and their association with particular structural abnormalities in the brain (i.e., periventricular white matter and temporal demyelination). The etiology of psychosis in MS has also not been explained adequately. Regional demyelination and the use of corticosteroids have been implicated, yet their mechanisms of action have not been elucidated. The present review addresses what is known at this point in time regarding the occurrence of psychosis in the context of MS, the data regarding possible etiological factors, and the implications of these data and suggestions regarding diagnosis and treatment. Future research should explore the underlying pathophysiology of psychosis and multiple sclerosis to further our understanding of the central nervous system disease process. This research could help determine the features which would guide clinicians in identifying patients at risk of developing psychosis in the context of MS, as well as propose the optimal pharmacological intervention.

Emotion perception in obsessive-compulsive disorder.

The purpose of the present study was to investigate the ability to perceive facial and vocal affect in a group of patients with obsessive-compulsive disorder (OCD) and to explore the specific emotions that might be troublesome for them. Participants were 25 patients with OCD and 25 healthy controls, matched for age, education, and gender. They were assessed with computerized tests of affect perception using visual faces [Kinneys Affect Matching Test (KAMT)], visual everyday scenarios [Fanties Cartoon Test (FCT)], and prosody [Affective Prosody Test (APT)], as well as a facial recognition test [Kinneys Identity Matching Test (KIMT)]. Severity of OCD symptoms in the patient group was measured with the Yale-Brown Obsessive Compulsive Scale. Patients with OCD were not impaired in the perception of emotion, in either the visual [still photographs (KAMT) or sketches of everyday scenarios (FCT)] or the vocal (APT) modality, as compared with age-, sex-, and education-matched healthy individuals. Moreover, patients with OCD did not differ from healthy individuals in discriminating facial identity (KIMT). With regard to each emotion type separately, patients performed equally well as healthy individuals in all the emotions examined. Emotion processing of both facial expressions and prosody does not appear to be deficient in patients with OCD (JINS, 2009, 15, 148-153).

Development of the Greek Verbal Learning Test: reliability, construct validity, and normative standards.

We developed a multiple-form list learning test appropriate for use with the Greek population and generated norms for clinical and research use. This task, the Greek Verbal Learning Test (GVLT), was based on the California Verbal Learning Test. We administered the standard version (Form A) to a sample of 354 healthy individuals, as well as two alternative forms (B and C) to a subgroup of the initial sample. Performance on the three forms was equivalent, and each test presented excellent internal consistency. We found good sensitivity and specificity in the testãs (Form A) utility in differentiating individuals with schizophrenia (n = 50) and individuals with traumatic brain injury (n = 53) from healthy adults. A multiple regression analysis indicated that age, education and sex predicted performance. Regression-based norms are also provided. Taken together, these data provide preliminary support for the reliability and construct validity of the GVLT.

Effects of sentence context on lexical ambiguity resolution in patients with schizophrenia.

Previous research has suggested that a failure in processing contextual information may account for the heterogeneous clinical manifestations and cognitive impairments observed in schizophrenia. In the domain of language, context processing in schizophrenia has been investigated mostly with single-word semantic priming paradigms; however, natural language comprehension depends on more than semantic relations between words. The present study aimed to systematically assess sentence context effects in homonym meaning activation in patients with schizophrenia. Fourteen patients with schizophrenia and 14 normal controls matched to the patients on sex, age, education and parental education, were examined using a cross-modal priming paradigm. Primes were sentences biasing the first, second, or neither meaning of a sentence-final equibiased homonym; targets were related to either the first or the second meaning of the homonym and appeared after an interstimulus interval (ISI) of 0ms or 750ms. Patients with schizophrenia exhibited a trend towards facilitation of both target types following unbiased sentences at ISI=0ms, similar to controls. However, in contrast to the pattern of selective target facilitation exhibited by control subjects following first- or second meaning-biased sentences, no significant target facilitation was observed in patients in the same condition. At ISI=750ms, patients did no longer exhibit significant target facilitation in any sentence context condition. This pattern of results is compatible with the assumption of a combined impairment in lexical (automatic spreading of activation within the semantic network) and extralexical (working memory) processes in patients with schizophrenia.