Summary of Sackheim Article by pychologist
Read this important summary of Sackheim’s ground-breaking work on electroshock:
Summary of ‘The Cognitive Effects of Electroconvulsive Therapy’,
Sackeim H, et al. (2007) Neuropsychophamacology, 31, 244-254.
Although numerous studies documenting cognitive deficits, particularly memory impairment, have been presented previously to the Health Select Committee, the Sackeim study is ‘the first large-scale, prospective study of objective cognitive outcomes of patients treated with ECT’. Prospective means following a sample over time rather than taking a ‘snap shot’ at just one time point. The 347 patients followed, for six months after ECT, certainly warrants the authors’ claim of being ‘large-scale’, relative to previous ECT studies.
Immediately after ECT patients performed significantly worse (compared to baseline performance) on a range of measures. The deficits following ECT were greatest for the measures assessing ‘memory for autobiographical events’, ‘retention of newly learned information’, ‘global cognitive status’ and ‘simple reaction time’.
A crucial question in ECT research is whether these immediate adverse effects, which are experienced by most ECT recipients, are temporary or permanent. While performance on some measures did improve over time, ‘Adverse cognitive effects were detected 6 months following treatment’. These adverse effects were particularly marked for memory for autobiographical events (retrograde amnesia). Thus after six months this sample of ECT patients, taken as a group, were significantly less able to remember events from their own lives. Furthermore for one in eight (12.4%) the brain damage was sufficiently severe for the researchers to classify it as ‘marked and persistent retrograde amnesia’.
Women and older people (the two groups who receive ECT at particularly high rates) were significantly more likely to suffer the adverse effects found in this study. This was also the case for people with lower IQ scores.
One argument used to counter previous research showing memory deficits in ECT recipients is that the memory deficits may be caused by the depression rather than the ECT. This study, however, found that ‘severity of depressive symptoms showed little relationship with the cognitive measures’.
Further evidence that the memory deficits were caused by the ECT is the finding that the number of shock treatments was positively related to the extent of the memory deficit.
Dr. John Read
Psychology Department, University of Auckland
February, 12, 2007.