We recently demonstrated that patients with major depression (MDD) with and without electroconvulsive therapy referral (ECTs vs. NECTs) qualitatively differ in neuropsychological profile. ECTs presented severe executive but minor visuospatial memory deficits, suggesting mainly frontostriatal involvement; NECTs presented the opposite pattern, compatible with temporohippocampal involvement. Here we follow up on ECT treatment effects on both cognitive domains.

15 ECTs were assessed with Hamilton Depression (HAMD-24), Hamilton Anxiety (HAMA) and Mini-Mental State Examination (MMSE) scales and 5 tests of the Cambridge Neuropsychological Test Automated Battery (CANTAB) at hospitalisation (PRE-ECT), immediately after ECT (POST-ECT) and 2 months later (FOLLOW-UP). ECTs at FOLLOW-UP were also compared to 15 matched non-psychiatric CONTROLS who underwent neuropsychological testing once.

There was significant clinical improvement (reflected by reduced HAMD-24 and HAMA scores: p < 0.001) between PRE-ECT and FOLLOW-UP. After a minor decline POST-ECT, MMSE scores showed significant increase at FOLLOW-UP (p < 0.02). At FOLLOW-UP, Paired Associates Learning (PAL) showed significant improvement (p < 0.001). Stockings of Cambridge (SOC) performance also improved (decrease in early abandonments, p < 0.04) POST-ECT and at FOLLOW-UP. However, clinical improvement did not result in improvement in Intra / Extradimensional Shift (IED): at FOLLOW-UP, ECT patients were indistinguishable from CONTROLS in all neuropsychological measures except IED (p < 0.04).

Clinically successful ECT treatment was accompanied by improved global cognitive functioning, visuospatial memory and spatial planning, but offered no benefit in attentional flexibility. This residual deficit suggests ‘trait’ frontostriatal involvement in this patient group.

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.

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

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.

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 dépressives.

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.

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).

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.

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.