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Contrasting patterns of deficits in visuospatial memory and executive function in patients with major depression with and without ECT referral

Published online by Cambridge University Press:  03 August 2010

E. Tsaltas*
Affiliation:
Experimental Psychology Laboratory, 1st Department of Psychiatry, Athens University Medical School, Eginition Hospital, Athens, Greece
S. Kalogerakou
Affiliation:
Experimental Psychology Laboratory, 1st Department of Psychiatry, Athens University Medical School, Eginition Hospital, Athens, Greece
V.-M. Papakosta
Affiliation:
Experimental Psychology Laboratory, 1st Department of Psychiatry, Athens University Medical School, Eginition Hospital, Athens, Greece
D. Kontis
Affiliation:
Experimental Psychology Laboratory, 1st Department of Psychiatry, Athens University Medical School, Eginition Hospital, Athens, Greece 1st Department of Psychiatry, Psychiatric Hospital of Attica, Athens, Greece
E. Theochari
Affiliation:
1st Department of Psychiatry, Psychiatric Hospital of Attica, Athens, Greece
M. Koutroumpi
Affiliation:
Experimental Psychology Laboratory, 1st Department of Psychiatry, Athens University Medical School, Eginition Hospital, Athens, Greece
E. Anyfandi
Affiliation:
Experimental Psychology Laboratory, 1st Department of Psychiatry, Athens University Medical School, Eginition Hospital, Athens, Greece
I. Michopoulos
Affiliation:
2nd Department of Psychiatry, Atticon Hospital, Athens University Medical School, Athens, Greece
C. Poulopoulou
Affiliation:
Experimental Neurophysiology Laboratory, Department of Neurology, Athens University Medical School, Eginition Hospital, Athens, Greece
G. Papadimitriou
Affiliation:
1st Department of Psychiatry, Psychiatric Hospital of Attica, Athens, Greece
P. Oulis
Affiliation:
1st Department of Psychiatry, Psychiatric Hospital of Attica, Athens, Greece
*
*Address for correspondence: Dr E. Tsaltas, D.Phil., Experimental Psychologist, Assistant Professor in Psychiatry, Experimental Psychology Laboratory, 1st Department of Psychiatry, Athens University Medical School, Eginition Hospital, 74, Vas. Sofias Ave., 115 28 Athens, Greece. (Email: [email protected])

Abstract

Background

The pretreatment neuropsychological profile of drug-resistant patients with major depressive disorder (MDD) referred for electroconvulsive therapy (ECT) may differ from that of their drug-respondent MDD counterparts. Such differences could help in identifying distinct MDD subtypes, thus offering insights into the neuropathology underlying differential treatment responses.

Method

Depressed patients with ECT referral (ECTs), depressed patients with no ECT referral (NECTs) and non-psychiatric Controls (matched groups, n=15) were assessed with memory and executive function tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB).

Results

ECTs scored significantly lower than NECTs in the Mini-Mental State Examination (MMSE; p=0.01). NECTs performed worse than Controls in the Paired Associates Learning (PAL) task (p<0.03; Control/NECT p<0.01) and the Spatial Recognition Memory (SRM) task (p<0.05; Controls/NECTs p<0.05); ECTs performed between Controls and NECTs, not differing from either. In the Intra/Extradimensional (IED) set-shifting task, ECTs performed worse that Controls and NECTS (IED: p<0.01; Controls/ECTs p<0.01), particularly in the shift phases, which suggests reduced attentional flexibility. In Stockings of Cambridge (SOC), ECTs abandoned the test early more often than Controls and NECTs (H=11, p<0.01) but ECTs who completed SOC performed comparably to the other two groups.

Conclusions

A double dissociation emerged from the comparison of cognitive profiles of ECT and NECT patients. ECTs showed executive deficits, particularly in attentional flexibility, but mild deficits in tests of visuospatial memory. NECTs presented the opposite pattern. This suggests predominantly frontostriatal involvement in ECT versus temporal involvement in NECT depressives.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 2010

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