Darragh Downey

Background: As uncertainty remains about whether clinical response influences cognitive function after electroconvulsive therapy (ECT) for depression, we examined the effect of remission status on cognitive function in depressed patients 4 months after a course of ECT.Method: A secondary analysis was undertaken on participants completing a randomised controlled trial of ketamine augmentation of ECT for depression who were categorised by remission status (MADRS ⩽10 v. >10) 4 months after ECT. Cognition was assessed with self-rated memory and neuropsychological tests of anterograde verbal and visual memory, autobiographical memory, verbal fluency and working memory. Patients were assessed through the study, healthy controls on a single occasion, and compared using analysis of variance.Results: At 4-month follow-up, remitted patients (N = 18) had a mean MADRS depression score of 3.8 (95% CI 2.2–5.4) compared with 27.2 (23.0–31.5) in non-remitted patients (N = 19), with no significant baseline differences between the two groups. Patients were impaired on all cognitive measures at baseline. There was no deterioration, with some measures improving, 4-months after ECT, at which time remitted patients had significantly improved self-rated memory, anterograde verbal memory and category verbal fluency compared with those remaining depressed. Self-rated memory correlated with category fluency and autobiographical memory at follow-up.Conclusions: We found no evidence of persistent impairment of cognition after ECT. Achieving remission improved subjective memory and verbal memory recall, but other aspects of cognitive function were not influenced by remission status. Self-rated memory may be useful to monitor the effects of ECT on longer-term memory.

Background: Reduced frontal cortex metabolism and blood flow in depression may be associated with low mood and cognitive impairment. Further reduction has been reported during a course of electroconvulsive therapy but it is not known if this relates to mood and cognitive changes caused by electroconvulsive therapy. Aims: The purpose of this study was to investigate frontal function while undertaking cognitive tasks in depressed patients compared with healthy controls, and following electroconvulsive therapy in patients. Methods: We measured frontal haemodynamic responses to a category verbal fluency task and a working memory N-back task using portable functional near infra-red spectroscopy (fNIRS) in 51 healthy controls and 18 severely depressed patients, 12 of whom were retested after the fourth treatment of a course of electroconvulsive therapy. Mood was assessed using the Montgomery Åsberg Depression Rating Scale and cognitive function using category Verbal Fluency from the Controlled Oral Word Association Test and Digit Span backwards. Results: Compared to healthy controls, depressed patients had bilaterally lower frontal oxyhaemoglobin responses to the cognitive tasks, although this was only significant for the N-Back task where performance correlated inversely with depression severity in patients. After four electroconvulsive therapy treatments oxyhaemoglobin responses were further reduced during the Verbal Fluency task but the changes did not correlate with mood or cognitive changes. Discussion: Our results confirmed a now extensive literature showing impaired frontal fNIRS oxyhaemoglobin responses to cognitive tasks in depression, and showed for the first time that these are further reduced during a course of electroconvulsive therapy. Further research is needed to investigate the biology and clinical utility of frontal fNIRS in psychiatric patients.

The relationship between altered default mode network (DMN) connectivity and abnormal serotonin function in major depressive disorder (MDD) has not been investigated. Using intravenous citalopram and resting-state fMRI, we investigated DMN intra-network connectivity and serotonin function in 77 healthy controls and patients with MDD. There were no significant main effects of MDD or citalopram on DMN intra-network connectivity; however, significant interactions indicated that group differences under saline were modified by citalopram. In MDD patients during saline infusion, in contrast with controls, the DMN (i) did not include the precuneus that was instead part of an anti-correlated network but (ii) did include amygdala that was part of the anti-correlated network in controls. Citalopram infusion in MDD patients restored the pattern seen in controls under saline. In healthy controls, citalopram infusion disengaged the precuneus from the DMN and engaged the amygdala, partially reproducing the abnormalities seen under saline in MDD. In exploratory analyses within the MDD group, greater rumination self-ratings were associated with greater intra-network connectivity of the anterior cingulate cortex with the DMN. We hypothesise that, in MDD, disengagement of the precuneus from the DMN relates to overgeneral memory bias in rumination. The opposite effect, with greater engagement of the amygdala in the DMN, reflects the negative valence of rumination. Reversal of these abnormalities by citalopram suggests that they may be related to impaired serotonin function. That citalopram engaged the amygdala in the DMN in controls may relate to the paradoxical effects on aversive processing seen with acute SSRIs in healthy subjects.

Functional magnetic resonance imaging (fMRI) has increasingly been employed to establish whether there is a specific brain neural network dedicated to maternal responsiveness. We undertook systematic review and meta-analysis of all studies in which healthy new mothers were exposed to visual stimuli of own versus other infants to determine the quality of evidence for a dedicated maternal neural network. Systematic literature review revealed a pattern of specific neural responses commonly induced by visual infant paradigms. Brain areas consistently reported as activated in mothers in response to own versus unknown infant included the left thalamus, bilateral pre-central gyrus, left limbic lobe, uncus, amygdala and left caudate. These regions are implicated in reward, attention, emotion processing and other core social cognitive skills. Meta-analysis, however, revealed a more limited subset of brain areas activated in mothers specifically in response to their own versus unknown infant and suggested considerable inter-study variability. Further work is needed if functional imaging is to become an objective tool for the assessment of neural pathways associated with distinct patterns of maternal care behaviour. Such a tool would be invaluable in developing biomarkers of neural activity associated with healthy maternal care and for monitoring treatment/intervention effects of costly parenting interventions.

Background: Electroconvulsive therapy (ECT) is the most effective acute treatment for severe depression, but there are concerns about its adverse cognitive effects. ECT may impair cognition through stimulation of glutamate receptors, and preliminary evidence has suggested that ketamine, a glutamate antagonist, may alleviate these effects. Ketamine has been shown to have a rapid, but temporary, antidepressant effect after a single infusion.Objective: To determine the efficacy and safety of adjunctive low-dose ketamine to reduce cognitive impairments caused by ECT and, secondarily, to improve symptomatic outcome.Design: Multicentre, two-arm, parallel-group, patient-randomised, placebo-controlled superiority trial.Setting: Eleven ECT suites based in seven NHS trusts in the north of England.Participants: Severely depressed hospitalised patients or outpatients who received ECT as part of their usual clinical care.Interventions: Patients were randomised to ketamine (0.5 mg/kg) or saline as an adjunct to their anaesthetic for their ECT course in a 1 : 1 ratio.Main outcome measures: The primary outcome was delayed verbal recall on the Hopkins Verbal Learning Task – Revised (HVLT-R) after four ECT treatments (mid-ECT), analysed using a Gaussian repeated measures model. Secondary outcomes included autobiographical, working and visual memory and verbal fluency, symptoms and quality of life; assessments occurred at mid-ECT, end of treatment and 1 and 4 months after the last ECT. Neuropsychological function was compared with that of healthy control subjects and a functional near-infrared spectroscopy (fNIRS) substudy investigated prefrontal cortex function. A patient survey of study participation was carried out.Results: Seventy-nine severely depressed patients were randomised to ketamine (0.5 mg/kg) or saline as an adjunct to their anaesthetic for their ECT course; the modified intention-to-treat sample included 70 patients. Compared with saline, adjunctive ketamine had no significant effect on HVLT-R delayed recall [treatment effect difference –0.43, 95% confidence interval (CI) –1.73 to 0.87], other neuropsychological outcomes, improvement in depression [difference in Montgomery–Åsberg Depression Rating Scale (MADRS) score of 0.44, 95% CI –1.03 to 1.91], the number of ECT treatments to remission (MADRS score of ≤ 10: 0.83, 95% CI –3.2 to 4.9), anxiety symptoms or quality of life. By the end of ECT treatment, 37% (saline 35%, ketamine 39%) of patients had remitted. Tolerability was similar in the two treatment arms; two patients had isolated transient psychological effects attributable to ketamine. Preliminary fNIRS analysis found that patients had blunted prefrontal cortical haemodynamic responses compared with control subjects during a verbal fluency task at baseline; this was further diminished at mid-ECT without modulation by ketamine. Greater haemodynamic responsivity to ECT appeared to be associated with a better clinical response. The majority of patients surveyed reported a positive experience of study participation.Conclusions: The results of the study do not support the use of adjunctive ketamine in routine ECT treatment in the NHS. Although no evidence of benefit was found for ketamine, moderate benefits or harms cannot be excluded, as recruitment was < 50% of that planned, limiting the power of the clinical trial. Low numbers also meant that in the fNIRS substudy the effect of ketamine could not be assessed and the other findings must be viewed as preliminary. Included patients were younger than those not included and had only limited cognitive impairment with ECT, limiting generalisation to more cognitively compromised patients. fNIRS appeared to be a potentially feasible portable brain imaging technology in severely ill patients and further research is warranted to investigate its clinical utility.Trial registration: Current Controlled Trials ISRCTN14689382.Funding: This project was funded by the Efficacy and Mechanism Evaluation programme, a Medical Research Council and National Institute for Health Research partnership.

Increasing evidence suggests that discrete neural networks that mediate emotion processing are activated when mothers respond to infant's images or cries. Accumulating data also indicate that natural variation in maternal caregiving behavior is related to maternal oxytocin (OT) levels. However, brain activation to infant cues has not been studied comparing mothers at disparate ends of the "maternal sensitivity" spectrum. Based on observed mother-infant play interaction at 4-6 months postpartum in 80 antenatally recruited mothers, 15 mothers with the highest sensitivity (HSMs) and 15 mothers with the lowest sensitivity (LSMs) were followed at 7-9 months using functional magnetic resonance imaging (fMRI) to examine brain responses to viewing videos of their "own" versus an "unknown" infant in 3 affect states (neutral, happy, and sad). Plasma OT measurements were taken from mothers following play interactions with their infant. Compared with LSMs, HSMs showed significantly greater brain activation in right superior temporal gyrus (STG) in response to own versus unknown neutral infant and to own happy versus neutral control. Changes in brain activation were significantly negatively correlated with plasma OT responses in HSMs mothers. Conversely, compared with HSMs, LSMs showed no significant activation difference in response to own infant separately or in contrast to unknown infant. Activation of STG may index sensitive maternal response to own infant stimuli. Sensitive parenting may have its unique profile in relation to brain responses which can act as biomarkers for future intervention studies that enhance sensitivity of maternal care. (PsycINFO Database Record