Spatial and Temporal Distribution of Information Processing in the Human Dorsal Anterior Cingulate Cortex.

The dorsal anterior cingulate cortex (dACC) is a key node in the human salience network. It has been ascribed motor, pain-processing and affective functions. However, the dynamics of information flow in this complex region and how it responds to inputs remain unclear and are difficult to study using non-invasive electrophysiology. The area is targeted by neurosurgery to treat neuropathic pain. During deep brain stimulation surgery, we recorded local field potentials from this region in humans during a decision-making task requiring motor output. We investigated the spatial and temporal distribution of information flow within the dACC. We demonstrate the existence of a distributed network within the anterior cingulate cortex where discrete nodes demonstrate directed communication following inputs. We show that this network anticipates and responds to the valence of feedback to actions. We further show that these network dynamics adapt following learning. Our results provide evidence for the integration of learning and the response to feedback in a key cognitive region.

Management of aneurysmal subarachnoid haemorrhage 17 years after the ISAT trial: a survey of current practice in the UK and Ireland.

Introduction: In the last two decades and driven by the International Subarachnoid Aneurysm Trial (ISAT), the management of aneurysmal subarachnoid haemorrhage (aSAH) has undergone extensive change from predominantly neurosurgical (clipping) to predominantly neuroradiological (coiling) treatment. In 2013, the UK's national Confidential Enquiry into Patient Outcome and Death (NCEPOD) recommended aSAH to be definitively treated within 48h of ictus. The aim of this survey was to assess how this recommendation is being followed across the UK and Ireland 17 years after ISAT and 6 years after the NCEPOD.Methods: An online survey consisting of 9 questions was electronically distributed to neurosurgical consultants and trainees. Missing or ambivalent data was collected or verified by emailing consultant neurosurgeons to ensure the coverage of all 32 neurosurgical units in the UK and Ireland.Results: Only 9 (28%) of units provide 7 days a week interventional neuroradiology service, but all 32 (100%) units have established networks with other neuroradiology centres to provide aSAH treatment within 48h of ictus assuming no delays in patient transfer. For aSAH patients requiring neurosurgical clipping, 27 (84%) of units provide (locally or through networks) aneurysm repair within 48h of ictus, whereas 5 (16%) units may breach this recommendation by keeping the aSAH patients that present after 5PM on Fridays and delaying their clipping to the subsequent Monday.Conclusion: Assuming no delays in patient transfer, 32 (100%) neurosurgical centres in the UK and Ireland meet the <48h ictus-to-treatment target for endovascular coiling and 27 (84%) units for neurosurgical clipping of aSAH.