Details of attention and learning change in first-episode schizophrenia

Abstract

Impaired attention and learning functions are common in schizophrenia. The details of this impairment, and how these change across time, are not well known. We aimed to compare the parameters of well-known attention and learning neuropsychological tests in first-episode schizophrenia (FES) patients and healthy controls in a 2-year follow-up period. The performance of 28-25 FES patients and pairwise matched healthy controls on the Continuous Performance Test-Identical Pairs, the revised Hopkins Verbal Learning Test, and the revised Brief Visuospatial Memory Test was compared at baseline and 2 years later. The attention dysfunction of the FES group was driven by slow reaction time and a comparative failure to identify correct hits. The reaction time was reduced somewhat across time in the patient group. Regarding the learning tasks, both groups increased their number of correct answers across trials. However, at each trial, the patient group exhibited lower scores, with a trend towards better visual learning performance across time. In summary, the FES patients were impaired in most of the parameters of the attention and learning tasks. Across time, modest improvements in reaction time and visual learning were displayed in the FES group. However, this group never caught up with the control group.

Relationships between abnormal neural activities and cognitive impairments in patients with drug-naive first-episode schizophrenia

“…In the present study, the dn-FES group showed severe and widespread cognitive deficits in all domains, and this observation was consistent with the previous studies that used the same instrument [5,35,36]. Schizophrenia has distinct cognitive impairments, including speed of processing [37], working memory [38], verbal learning [39], reasoning/problem solving [40], visual learning [41], attention/vigilance [42], and social cognition [43]. Our results showed that cognitive deficits were present at the onset of schizophrenia without considering the several factors, such as long-term antipsychotic treatment and prolonged illness course.…”

Amplitude of low-frequency fluctuation (ALFF) may be associated with cognitive impairment in schizophrenia: a correlation study

“…We found that SZ patients showed cognitive impairments in all domains, which is consistent with previous studies that used the same cognitive measurement [15]. Deficits processing speed [33], working memory [34], verbal learning [7], reasoning/problem-solving [35], visual learning [36], and attention/vigilance [37] were found in SZ patients. Similar cognitive impairments were also reported in studies investigating patients with other psychiatric diagnoses [38–41]; however, the cognitive deficits were not as severe or as widespread as those seen in SZ patients.…”

Synaptic Proteome Alterations in the Primary Auditory Cortex of Individuals With Schizophrenia

“…P atients with schizophrenia display impairments in the processing of auditory sensory information, [1][2][3][4] including auditory event-related potentials (eg, mismatch negativity) 1,2,5,6 that are generated in layer 3 of the primary auditory cortex (A1). [7][8][9] Many individuals with schizophrenia also have deficits in auditory learning, 10 limiting their functional recovery during targeted sensory and cognitive training. 11 In A1, as in other cortical regions, learning requires the formation and stabilization of new dendritic spines, [12][13][14] and decreased density of layer 3 dendritic spines has been reproducibly observed in multiple brain regions in patients with schizophrenia, including A1.…”