ERP/CSD indices of impaired verbal working memory subprocesses in schizophrenia.
To disentangle subprocesses of verbal working memory deficits in schizophrenia, long EEG epochs (>10 s) were recorded from 13 patients and 17 healthy adults during a visual word serial position test. ERP generator patterns were summarized by temporal PCA from reference-free current source density (CSD) waveforms to sharpen 31-channel topographies. Patients showed poorer performance and reduced left inferior parietotemporal P3 source. Build-up of mid-frontal negative slow wave (SW) in controls during item encoding, integration, and active maintenance was absent in patients, whereas a sustained mid-frontal SW sink during the retention interval was comparable across groups. Mid-frontal SW sinks (encoding and retention periods) and posterior SW sinks and sources (encoding only) were related to performance in controls only. Data suggest disturbed processes in a frontal-parietotemporal network in schizophrenia, affecting encoding and early item storage.
Kayser
Jürgen
J
Department of Psychiatry, Columbia University College of Physicians & Surgeons, New York, New York, USA. kayserj@pi.cpmc.columbia.edu
Tenke
Craig E
CE
Gates
Nathan A
NA
Kroppmann
Chris J
CJ
Gil
Roberto B
RB
Bruder
Gerard E
GE
D000293:Adolescent; D000328:Adult; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D025341:Principal Component Analysis; D012565:Schizophrenic Psychology