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Incentives tend to drive improvements in performance. But when incentives get too high, we can “choke under pressure” and underperform when it matters most. What neural processes might lead to choking under pressure? We studied Rhesus monkeys performing a challenging reaching task in which they underperform when an unusually large “jackpot” reward is at stake. We observed a collapse in neural information about upcoming movements for jackpot rewards: in the motor cortex, neural planning signals became less distinguishable for different reach directions when a jackpot reward was made available. We conclude that neural signals of reward and motor planning interact in the motor cortex in a manner that can explain why we choke under pressure.One-Sentence SummaryIn response to exceptionally large reward cues, animals can “choke under pressure”, and this corresponds to a collapse in the neural information about upcoming movements.

Long-term high-fidelity electroencephalogram (EEG) recordings are critical for clinical and brain science applications. Conductive liquid-like or solid-like wet interface materials have been conventionally used as reliable interfaces for EEG recording. However, because of their simplex liquid or solid phase, electrodes with them as interfaces confront inadequate dynamic adaptability to hairy scalp, which makes it challenging to maintain stable and efficient contact of electrodes with scalp for long-term EEG recording. Here, we develop an on-skin paintable conductive biogel that shows temperature-controlled reversible fluid-gel transition to address the abovementioned limitation. This phase transition endows the biogel with unique on-skin paintability and in situ gelatinization, establishing conformal contact and dynamic compliance of electrodes with hairy scalp. The biogel is demonstrated as an efficient interface for long-term high-quality EEG recording over several days and for the high-performance capture and classification of evoked potentials. The paintable biogel offers a biocompatible and long-term reliable interface for EEG-based systems.

The cardiovascular properties of NSP-804 (4,5-dihydro-6-[4-[(2-methyl-3-oxo-1-cyclopentenyl)-amino] phenyl]-3(2H)-pyridazinone) and NSP-805 (4,5-dihydro-5-methyl-6-[4-[(2-methyl-3-oxo-1-cyclopentenyl) amino]phenyl]-3(2H)-pyridazinone), novel cardiotonic agents, were investigated in vitro and in vivo in comparison with those of other cardiotonic agents. In isolated guinea pig left atria, the positive inotropic EC50 values (microM) in order of potency were about 0.18 (NSP-805), 0.39 (indolidan), 1.1 (MCI-154), 1.7 (NSP-804, milrinone), 2.0 (denopamine), 4.0 (papaverine), 4.4 3-isobutyl-1-methylxanthine, IBMX, 6.5 (imazodan), and 27 (amrinone). In anesthetized dogs, intravenous (i.v.) injection of NSP-804 and NSP-805 produced dose-dependent increases in left ventricular VVdp/dtmax and decreases in aortic blood pressure (ABP) with relatively small increases in heart rate (HR). The ED50 values (micrograms/kg) for LVdP/dtmax of NSP-804, NSP-805, denopamine, milrinone, MCI-154, and indolidan were 15, 12, 22, 23, 15, and 7.3, respectively. When the drugs were administered intraduodenally to anesthetized dogs, the ED50 values (micrograms/kg) for LVdP/dtmax of NSP-804, NSP-805, milrinone and indolidan were approximately 30, 10, 200, and 25 respectively. In the propranolol-induced heart failure model, NSP-804 and NSP-805 completely improved the hemodynamic state of heart failure to normal levels. The in vitro positive inotropic effects of NSP-804 and NSP-805 were accompanied by increases in tissue cyclic AMP and abolished by carbachol. NSP-805 was the most potent and selective inhibitor of guinea pig cardiac phosphodiesterase (PDE) III among the agents examined, and NSP-804 was a potent and selective inhibitor of PDE III similar to indolidan. The cardiovascular properties determined in this study suggest that both NSP-804 and NSP-805 may have beneficial effects for treatment of congestive heart failure (CHF).

A new insecticide, N-methyl-N-(1-naphthyl) fluoroacetamide (MNFA), was studied in a variety of species. The toxicity varied markedly with species. Guinea pigs, rabbits, dogs, and cats were found to be extremely sensitive to MNFA, whereas mice, rats, and monkeys were relatively less sensitive. In subacute toxicity studies in rats, aspermatogenesis was found in some tubules of the testis from the rats of the two high dose groups. Destruction of the germinal epithelium was more striking in mature cell series than in immature cell series. Small to moderate dose of MNFA, below 2.5 mg/kg, did not produce significant changes in the testis. The higher the dose of the agent, the lower was the systolic arterial blood pressure of male rats. The reduction ranged from 5 to 20% of the normal blood pressure. The blood pressure reduction was not accompanied by gross or microscopic changes of morphology of the cardiovascular system or kidney.

N -Methyl- N -(1-naphthyl)monofluoroacetamide (MNFA), a derivative of monofluoroacetic acid, is an effective pesticide with low toxicity for most mammals. The biochemical effect of this compound was investigated. After a single dose the citrate level rose in the heart of the rat and monkey and in the kidney of the guinea pig. A chronic toxicity experiment showed there was an increase in the citrate level only in the testis of rats receiving 10 mg/kg/day of MNFA for 180 days and a decrease in the level in the liver and kidney as compared with animals receiving a single dose. The lack of toxicity associated with chronic administration may be due to accelerated detoxication in the liver and kidney as a consequence of metabolism in the animal body. The hydrolysis of MNFA by liver homogenates was closely related to the acute toxicity. The enzyme activity in the guinea pig was about 35 times that of the rat or mouse. The product of the hydrolysis of MNFA by liver homogenates of guinea pigs, rats, and mice was N -methyl-1-naphthylamine. The LD50 of MNFA, a N-CH 3 compound of NFA, was 3.1 times that of NFA, and the amount hydrolyzed after 30 minutes incubation was about one-fifth.

A new anti-inflammatory proteinase designated as kinonase BI has been isolated from the mixture of kinonases produced by Streptomyces kinoluteus. Kinonase BI is purified by gradient column chromatography on DEAE-cellulose and gel filtration on a column of Sephadex G-75. Kinonase BI is considered to be a neutral proteinase of microbial origin. Kinonase BI is of acidic protein nature having pH optimum at 6.5 and optimum temperature at 55° against casein. Kinonase BI is rather stable in a solution of pH 5-9, but labile specially of acidic pH or by heating at 70° for 10 min. The proteolytic activity of kinonase BI is almost lost by addition of 10-3M of a heavy metal ion, Cu2+ or Hg2+, and ethylenediaminetetraacetic acid, but not by addition of ω-chloroacetophenone, p-chloromercuribenzoate diisopropylfluorophosphate and potato trypsin inhibitor at the same concentration. Kinonase BI hydrolyzes bradykinin to arginylprolylprolylglycine, phenyalanylserylproline and phenylalanylarginine. The anti-inflammatory activity on carrageenin-induced edema is observed in kinonase BI at the same level as in kinonase AI or AIII. Kinonase AII containing a trace of kinonase AI is recovered also from the mixture of kinonases. Kinonase AII is presumed to be a kind of leucine amino peptidases. Bradykinin is not hydrolyzed by kinonase AII and the anti-inflammatory activity is not observed in kinonase AII.