Course of neurological soft signs in first-episode schizophrenia: Relationship with negative symptoms and cognitive performances

Abstract

This prospective study examined the course of neurological soft signs (NSS) in patients with first-episode schizophrenia and its relationship with negative symptoms and cognitive functions. One hundred and forty-five patients with first-episode schizophrenia were recruited, 29 were classified as having prominent negative symptoms. NSS and neuropsychological measures were administered to all patients and 62 healthy controls at baseline. Patients were then followed-up prospectively at six-month intervals for up to a year. Patients with prominent negative symptoms exhibited significantly more motor coordination signs and total NSS than patients without prominent negative symptoms. Patients with prominent negative symptoms performed worse than patients without negative symptoms in working memory functions but not other fronto-parietal or fronto-temporal functions. Linear growth model for binary data showed that the prominent negative symptoms were stable over time. Despite general improvement in NSS and neuropsychological functions, the prominent negative symptoms group still exhibited poorer motor coordination and higher levels of NSS, as well as poorer working memory than patients without prominent negative symptoms. Two distinct subtypes of first-episode patients could be distinguished by NSS and prominent negative symptoms.

22q11 microdeletion syndrome and ultra‐high risk for psychosis: The role of neurological soft signs as an independent marker of vulnerability for psychosis

“…In fact, we have found a positive correlation only between the speed of timed activities and negative symptoms in UHR subjects. This result is similar to that found by Chan et al () in patients with schizophrenia. The negative symptoms are correlated to a dysfunction of the meso‐cortical system.…”

“…Volumetric abnormalities such as reduction of the cortex in the frontal, parietal, temporal and occipital lobes as well as in cerebellum and hippocampus have been reported in individual with 22q11DS. On the contrary, the corpus callosum shows an increased volume (Chow et al, 2011;Shashi, Francis, Hooper, et al, 2012). Similar patterns of cerebral abnormalities have been described in schizophrenic patients without 22q11DS (Murphy, 2002).…”

“…This system originates in the ventral tegmental area and projects to the neocortex, particular to the prefrontal cortex. The dopaminergic dysfunction in this area can produce not only the negative symptoms, but also the neurocognitive deficits in patients with schizophrenia (Chan et al, ). Since we did not found a strong correlation between NSS and positive and negative symptoms in the two clinical populations examined, we hypothesize that NSS could be indicators of atypical neurodevelopment and vulnerability to psychosis independent from the psychopathology.…”

Neurological Soft Signs in Schizophrenia: An Update on the State- versus Trait-Perspective

“…We identified 26 studies (see Table 1 ) which had performed follow-up assessments of patients diagnosed with schizophrenia or related disorders. These studies were presented by 18 groups, 3 of which ( 29 , 31 , 37 – 39 , 41 – 43 , 47 , 52 , 53 ) had carried out two to five studies each. Two other groups published two to three papers each on different follow-up examinations of one patient samples ( 30 , 48 – 50 , 58 ).…”

“…Researchers reported more extensively on negative symptoms compared to other symptoms present at the catamnestic examination. Many groups found a positive or increasing correlation over time between total NSS scores and negative symptoms ( 30 , 37 , 40 , 42 , 44 , 48 – 53 , 58 ), as well as correlations between motor signs and negative symptoms ( 39 , 47 ). One group described partial correlations of negative symptoms with primitive reflexes ( 34 ).…”