Mismatch negativity indexes illness-specific impairments of cortical plasticity in schizophrenia: a comparison with bipolar disorder and Alzheimer's disease.

Cognitive impairment is an important predictor of functional outcome in patients with schizophrenia, yet its neurobiology is still incompletely understood. Neuropathological evidence of impaired synaptic connectivity and NMDA receptor-dependent transmission in superior temporal cortex motivated us to explore the correlation of in vivo mismatch negativity (MMN) with cognitive status in patients with schizophrenia. MMN elicited in a roving stimulus paradigm displayed a response proportional to the number of stimulus repetitions (memory trace effect).

Fibrillary astrocytes are decreased in the subgenual cingulate in schizophrenia.

Decreases in astrocyte density and in glial fibrillary acid protein (GFAP) mRNA in the anterior cingulate cortex have been reported changed in mood and affective disorders. Our study examines the relative density and frequency of fibrillary and gemistocytic astrocytes in the white matter of the subgenual cingulate cortex in 11 schizophrenia, 16 bipolar disorder, 20 major depression and 20 normal control cases. Serial coronal sections were stained with H&E for anatomical guidance and GFAP immunohistochemistry for astrocyte identification.

Astrocyte decrease in the subgenual cingulate and callosal genu in schizophrenia.

Decreases in glial cell density and in GFAP mRNA in the anterior cingulate cortex have been reported in schizophrenia, bipolar disorder and major depressive disorder. Our study examines astrocyte and oligodendrocyte density in the white and grey matter of the subgenual cingulate cortex, and at the midline of the genu of the corpus callosum, in schizophrenia, bipolar disorder, depression and normal control cases. Serial coronal sections were stained with H and E for anatomical guidance, cresyl haematoxylin for oligodendrocyte identification and GFAP immunohistochemistry for astrocyte identification.

Name relearning in elderly patients with schizophrenia: episodic and temporary, not semantic and permanent.

Introduction: Recent reports of lexical-semantic deficits in patients with schizophrenia (Laws, Al-Uzri, & Mortimer, 2000; Laws, McKenna, & Kondel, 1998) suggest that younger patients have problems accessing intact memories and older patients show apparent "loss" of the lexical-semantic memory representations themselves.

Methods: Picture naming for everyday items was examined in a unique series of elderly patients with schizophrenia (n = 10) with a mean illness duration of 45.5 years; and compared with that in patients with probable Alzheimer's disease (n = 18) and elderly healthy controls (n = 27).

Down-regulation of Dickkopf 3, a regulator of the Wnt signalling pathway, in elderly schizophrenic subjects.

The aetiology of schizophrenia is complex and the pathological mechanisms involved are still not fully understood. The aim of this project was to gain insight into the underlying molecular changes occurring in schizophrenia through the analysis of gene expression. Using suppression subtractive hybridization to isolate differentially expressed genes in superior temporal cortex (BA22), we detected one prominent sequence with reduced expression in schizophrenia and represented in at least nine clones.

Mismatch negativity potentials and cognitive impairment in schizophrenia.

Cognitive impairment in schizophrenia is an important predictor of clinical and social outcome. In this preliminary study, the correlation between cognitive status and deficits in mismatch negativity (MMN) generation was explored. The MMN response to tone duration deviants was recorded using a new stimulation protocol with continuously changing ('roving') standard stimuli in order to measure the effect of standard repetitions on MMN (memory trace effect).

Intellectual differences between schizophrenic patients and normal controls across the adult lifespan.

A debate persists about whether IQ declines during the duration of schizophrenia or whether an early deficit remains static across the lifespan. To examine this, we measured estimated current IQ (Quick Test Revised: QTR) and estimated premorbid IQ (National Adult Reading Test: NART) in schizophrenic patients (n=110) and matched healthy controls (n=71) across a wide age range (20-88). Age correlated negatively with NART and QTR IQ for schizophrenic patients, but not for controls.

A 28-week comparison of ziprasidone and haloperidol in outpatients with stable schizophrenia.

Background: Ziprasidone is a novel antipsychotic with a unique pharmacologic profile. This study compared ziprasidone with the conventional antipsychotic haloperidol in outpatients with stable schizophrenia.

Method: Three hundred one outpatients with stable chronic or subchronic schizophrenia (DSM-III-R) were randomized and participated in this double-blind, multicenter, parallel-group clinical study comparing flexible-dose oral ziprasidone, 80-160 mg/day (N = 148), with haloperidol, 5-15 mg/day (N = 153), over 28 weeks.

A volumetric biochemical niacin flush-based index that noninvasively detects fatty acid deficiency in schizophrenia.

(1) It is possible to investigate aspects of phospholipid-related signal transduction in humans noninvasively using the niacin skin flush test. (2) Patients with schizophrenia have previously been reported to show a reduced flushing response. (3) The aim of this study was to devise a comprehensive index of cutaneous response to the niacin test, incorporating aqueous methyl nicotinate concentration and time, and to test this index in schizophrenia.

Impairment in frontal but not temporal components of mismatch negativity in schizophrenia.

Impairment in mismatch negativity (MMN) potentials is a robust finding in schizophrenia. While previous studies suggested that MMN in man is generated by a single dipole source bilaterally in the primary auditory cortex, more recent data modified this assumption by showing differential modulation of MMN components over the frontal and temporal scalp. Here we used a roving standard experiment to record mismatch potentials to tone duration deviants with the aim to detect robust temporal and frontal mismatch components.