Electrophysiological correlates of feedback processing in subarachnoid hemorrhage patients.

Patients with subarachnoid hemorrhage (SAH) secondary to anterior communicating artery (AComA) aneurysm rupture often experience deficits in executive functioning and decision-making. Effective decision-making is based on the subjects' ability to adjust their performance based on feedback processing, ascribing either positive or negative value to the actions performed reinforcing the most adaptive behavior in an appropriate temporal framework. A crucial brain structure associated to feedback processing is the medial prefrontal cortex (mPFC), a brain region frequently damaged after AComA aneurysm rupture. In the present study, we recorded electrophysiological responses (event-related potentials (ERPs') and oscillatory activity (time frequency analysis) during a gambling task in a series of 15 SAH patients. Previous studies have identified a feedback related negativity (FRN) component associated with an increase on frontal medial theta power in response to negative feedback or monetary losses, which is thought to reflect the degree of negative prediction error. Our findings show a decreased FRN component in response to negative feedback and a delayed increase of theta oscillatory activity in the SAH patient group when compared to the healthy controls, indicating a reduced sensitivity to negative feedback processing and an effortful signaling of cognitive control and monitoring processes lengthened in time, respectively. These results provide us with novel neurophysiological markers regarding feedback processing and performance monitoring patterns in SAH patients, illustrating a dysfunctional reinforcement learning system probably contributing to the maladaptive day-to-day functioning in these patients.

Outcomes After Direct Thrombectomy or Combined Intravenous and Endovascular Treatment Are Not Different.

BACKGROUND AND PURPOSE: Whether intravenous thrombolysis adds a further benefit when given before endovascular thrombectomy (EVT) is unknown. Furthermore, intravenous thrombolysis delays time to groin puncture, mainly among drip and ship patients. METHODS: Using region-wide registry data, we selected cases that received direct EVT or combined intravenous thrombolysis+EVT for anterior circulation strokes between January 2011 and October 2015. Treatment effect was estimated by stratification on a propensity score. The average odds ratios for the association of treatment with good outcome and death at 3 months and symptomatic bleedings at 24 hours were calculated with the Mantel-Haenszel test statistic. RESULTS: We included 599 direct EVT patients and 567 patients with combined treatment. Stratification through propensity score achieved balance of baseline characteristics across treatment groups. There was no association between treatment modality and good outcome (odds ratio, 0.97; 95% confidence interval, 0.74-1.27), death (odds ratio, 1.07; 95% confidence interval, 0.74-1.54), or symptomatic bleedings (odds ratio, 0.56; 95% confidence interval, 0.25-1.27). CONCLUSIONS: This observational study suggests that outcomes after direct EVT or combined intravenous thrombolysis+EVT are not different. If confirmed by a randomized controlled trial, it may have a significant impact on organization of stroke systems of care.

Decision-making impairment on the Iowa Gambling Task after endovascular coiling or neurosurgical clipping for ruptured anterior communicating artery aneurysm.

OBJECTIVE: To investigate decision-making deficits after anterior communicating artery aneurysm (ACoA) rupture and to compare the effects of two treatments. METHOD: The sample included 40 patients with subarachnoid hemorrhage secondary to ruptured ACoA with a favorable neurological outcome and a control group of 31 subjects matched by age, sex, and years of education. Twenty patients had surgical interventions (clipping) and 20 had received endovascular treatment. Decision-making was assessed by the Iowa Gambling Task (IGT). We used the Expectancy Valence model to examine the different components associated with the IGT. RESULTS: ACoA patients performed significantly worse on the IGT than controls, we observed poorly performance on IGT in 70% of the patients. Comparing the groups according to type of intervention, we found that clipped patients performed significantly worse than controls on the IGT, whereas coiled patients did not differ significantly from controls or clipped patients; however, coiled patients performed worse than controls on the last block of the task. Patients with frontal lesions selected significantly more cards from the disadvantageous deck. IGT performance correlated with other tests of executive functions such as the perseverative errors and non perseverative errors of Wisconsin Card Sorting Tests, and verbal fluency test, but not with working memory tests. According to the Expectancy Valence model, patients with frontal lesions showed a greater tendency to focus on recent outcomes and ignore or rapidly discount past outcomes, and tended to have a more erratic response pattern. CONCLUSIONS: Our results suggest that patients with subarachnoid hemorrhage secondary to ruptured ACoA have deficits in decision-making under ambiguity. The main cause of this deficit is the presence of frontal lesions. Moreover, clipped patients, but not coiled patients, showed deficits in taking decisions in comparison with controls. Our results suggest that the IGT may help to identify neuropsychological sequelae in these patients.

Olfactory dysfunction after subarachnoid hemorrhage caused by ruptured aneurysms of the anterior communicating artery. Clinical article.

OBJECT: Olfactory dysfunction has an important impact on quality of life. In patients with subarachnoid hemorrhage (SAH), anosmia has mainly been reported after surgery for aneurysms of the anterior communicating artery (ACoA). The authors studied whether and how frequently patients with ACoA aneurysms present with smell identification deficits in 2 treatment groups (endovascular and surgical treatment). METHODS: A prospective study was conducted of patients with SAH caused by ruptured ACoAs and who had a Glasgow Outcome Scale score of 1 or 2, in comparison with a control group matched by age and sex. Olfactory function was assessed using the University of Pennsylvania Smell Identification Test (UPSIT). RESULTS: A total of 39 patients were enrolled. A marked olfactory impairment was observed in patients with ruptured ACoAs compared with the control group (p < 0.001). Seventeen patients with ruptured ACoAs (44%) compared with 1 patient in the control group (3%) showed a smell identification deficit according to performance on the UPSIT (p < 0.001). Both groups that underwent treatment presented with olfactory impairment. Ten (59%) of 17 patients who underwent aneurysmal clip placement versus 6 (28.5%) of 21 patients who underwent coil embolization scored below the 25th percentile on the UPSIT, and surgical patients also performed worse than endovascular patients (p = 0.048). The authors observed a worse performance on the olfactory test in patients subjected to endovascular coil embolization when cerebral vasospasm (p = 0.037) or frontal cerebral lesions (p = 0.009) were present. This difference was not observed in patients who underwent surgery. CONCLUSIONS: Olfactory disorders after SAH caused by rupture of the ACoA are very frequent and were present in both treatment groups. Cerebral vasospasm and frontal lobe lesions are related to worse performance on an olfactory test in patients undergoing endovascular coil embolization.