Improved Reaction Time Research Articles

Enhancement of selective attention by tDCS: Interaction with interference in a Sternberg task

Transcranial Direct Current Stimulation (tDCS) enhances performance on working memory tasks. However, such effects may be dependent on modulation of specific aspects of working memory. We therefore tested the hypothesis that tDCS improves selective attention in the context of a Sternberg task. Subjects had to maintain a memory set while responding to distracter stimuli. Probes consisted of one item from the memory set, and one item that could have been presented as a distracter. TDCS was found to improve reaction time significantly only when the incorrect choice had been a distracter stimulus. The results thus support the notion that tDCS effects on working memory might be mediated by a specific effect on selective attention.

Development of a Piezoelectric Transducers System to Improve Mixing of Fluids

Abstract The growing interest in microfluidic devices lead to the necessity of handling fluids at micro-scales and improve reaction times, which is intrinsically related to a fast and efficient mixing process. The 96 well microplates used for biochemical analysis, usually require fluids mixing before analysis, which is commonly performed by mechanically stirring. In this work, it was developed an electric actuating system based on piezoelectric PZT (Lead Zirconate Titanate) and PVDF (Polyvinylidene fluoride) transducers, which are to be placed under the microplate, in order to generate and transmit acoustic waves to the wells. A fast and efficient mixing process was achieved and demonstrated thought a qualitative approach.

Determining skill transferability of action games as a method to reduce in-vehicle phone distractions

Distracted driving has been shown to be a safety issue in numerous studies. To combat this problem, in-vehicle technology, legislation, media interventions, and other methods have been proposed and attempted. However research indicates that the drivers themselves may circumvent, ignore, or not be able to react in time for these interventions to be effective. Therefore research into training programs for drivers may improve reaction time under distraction. Research indicates that action game players have faster reaction times and more attentional resources than non-players on paper-based tests. However, transferability to driving has not been studied yet. This paper outlines a study to determine if action game players perform better at a driving task based on frequency of game-play. Participants will be placed into two groups of play (high vs. low) and tested against two levels of distraction (none vs. phone conversation). It is expected that participants who play higher frequency of action games will perform better under distraction than lower frequency players. Driver performance, conversation recall, frequency and durations of eye fixations will be analyzed based on previous research which has validated those variables as a measure of distraction and higher workload.

A comparison of semantic and spatial stimulus-response compatibility effects for human-machine interface design

The effects of semantic and spatial stimulus-response (S-R) compatibility were examined and compared with the use of an auditory choice reaction task paradigm in this experiment. Twenty-two participants responded to speech and non-speech signals presented at the left and right ears and were asked to respond to different conditions of congruence and incongruence of semantic and location codes of signals and responses. The results showed that participants processed the non-speech signals faster than the speech signals. The presence of both semantic and spatial compatibility for signals and responses was found to improve reaction time and response accuracy. Compared with spatial compatibility, the effect of semantic compatibility influences human performance more. Based on the results, practical ergonomics recommendations for enhanced human-machine interfaces were formulated which help industrial designers to improve overall system performance in machinery and equipment design.

Dose-dependent effects of endotoxin on neurobehavioral functions in humans.

Clinical and experimental evidence document that inflammation and increased peripheral cytokine levels are associated with depression-like symptoms and neuropsychological disturbances in humans. However, it remains unclear whether and to what extent cognitive functions like memory and attention are affected by and related to the dose of the inflammatory stimulus. Thus, in a cross-over, double-blind, experimental approach, healthy male volunteers were administered with either placebo or bacterial lipopolysaccharide (LPS) at doses of 0.4 (n = 18) or 0.8 ng/kg of body weight (n = 16). Pro- and anti-inflammatory cytokines, norephinephrine and cortisol concentrations were analyzed before and 1, 1.75, 3, 4, 6, and 24 h after injection. In addition, changes in mood and anxiety levels were determined together with working memory (n-back task) and long term memory performance (recall of emotional and neutral pictures of the International Affective Picture System). Endotoxin administration caused a profound transient physiological response with dose-related elevations in body temperature and heart rate, increases in plasma interleukin (IL)-6, IL-10, tumor necrosis factor (TNF)-α and IL-1 receptor antagonist (IL-1ra), salivary and plasma cortisol, and plasma norepinephrine. These changes were accompanied by dose-related decreased mood and increased anxiety levels. LPS administration did not affect accuracy in working memory performance but improved reaction time in the high-dose LPS condition compared to the control conditon. In contrast, long-term memory performance was impaired selectively for emotional stimuli after administration of the lower but not of the higher dose of LPS. These data suggest the existence of at least two counter-acting mechanisms, one promoting and one inhibiting cognitive performance during acute systemic inflammation.

Effects of l-theanine on attention and reaction time response

Previous human studies revealed that l-theanine influences brain function. The current study was designed to evaluate the affect of l-theanine (Suntheanine®) on attention and reaction time response in 18 normal healthy University student volunteers. In accordance with preliminary analysis of the manifest anxiety scale (MAS), the subjects were divided into two groups referred to as high anxiety propensity group and the minimal anxiety propensity group. Both groups received l-theanine (200 mg/100 ml water) and placebo (100 ml water) in a double blind repeated measurement design protocol. Assessments were performed for 15–60 min after consumption under a relaxed condition upon exerting an experimentally induced visual attentional task as well as audio response tests. Self-reports of anxiety as State-Trait Anxiety Inventory (STAI) was characterized at post experiments. Alpha bands electroencephalographic activity and heart rate were recorded throughout the trial. The results demonstrate the significant enhanced activity of alpha bands, descending heart rate, elevated visual attentional performance, and improved reaction time response among high anxiety propensity subjects compared to a placebo. However, no significant differences were noticed among subjects with a minimal anxiety propensity. Results evidently demonstrated that l-theanine clearly has a pronounced effect on attention performance and reaction time response in normal healthy subjects prone to have high anxiety.

Effect of a high protein meat diet on muscle and cognitive functions: A randomised controlled dietary intervention trial in healthy men

Recommendations to use other criteria than N-balance for defining protein requirements have been proposed. However, little evidence to support other measures such as physiological functions is available. To investigate the effects of a usual (UP) versus a high protein (HP) diet on muscle function, cognitive function, quality of life and biochemical regulators of protein metabolism. A randomised intervention study was conducted with 23 healthy males (aged 19-31 yrs). All subjects consumed a Usual Protein (UP) diet (1.5 g protein/kg BW) for a 1-wk run-in period before the intervention period where they were assigned to either a UP or a High Protein (HP) diet (3.0 g protein/kg BW) for 3-wks with controlled intake of food and beverages. Blood and urine samples were taken along with measurements of physiological functions at baseline and at the end of the intervention period. The HP group improved their reaction time significantly compared with the UP group. Branched chain amino acids and phenylalanine in plasma were significantly increased following the HP diet, which may explain the improved reaction time. Healthy young males fed a HP diet improved reaction time. No adverse effects of the HP diet were observed. This trial was registered at www.clinicaltrials.gov as NCT00621231.

Biofeedback Reaction-Time Training: Toward Olympic Gold

As part of a larger training program, applying a new biofeedback protocol for improving reaction time (RT) performance among elite speed skaters at the Canadian Speedskating National Training Center in Montreal, Canada, provided an advantage at the Vancouver 2010 Olympic Games, allowing athletes to assert themselves and claim the best starting position during the event. Each athlete participated in a twice-weekly biofeedback RT training for 5 weeks, for a total of 600 RT practice trials, simulating speed-skating activities such as reacting to commands of “go to the start,” “ready,” and the sound of a signal from a gun to start. There was an overall improvement in RT performance from the beginning to the end of the 5-week period, with the largest improvement occurring between Weeks 4 and 5 of the training, F(1, 9) = 679.2, p = .001. The results suggest that biofeedback protocols will become an essential part of a winning strategy for future interventions in speed skater training.

Neuronavigation Increases the Physiologic and Behavioral Effects of Low-Frequency rTMS of Primary Motor Cortex in Healthy Subjects

Low-frequency repetitive transcranial magnetic stimulation (rTMS) can exert local and inter-hemispheric neuromodulatory effects on cortical excitability. These physiologic effects can translate into changes in motor behavior, and may offer valuable therapeutic interventions in recovery from stroke. Neuronavigated TMS can maximize accurate and consistent targeting of a given cortical region, but is a lot more involved that conventional TMS. We aimed to assess whether neuronavigation enhances the physiologic and behavioral effects of low-frequency rTMS. Ten healthy subjects underwent two experimental sessions during which they received 1600 pulses of either navigated or non-navigated 1 Hz rTMS at 90% of the resting motor threshold (RMT) intensity over the motor cortical representation for left first dorsal interosseous (FDI) muscle. We compared the effects of navigated and non-navigated rTMS on motor-evoked potentials (MEPs) to single-pulse TMS, intracortical inhibition (ICI) and intracortical facilitation (ICF) by paired-pulse TMS, and performance in various behavioral tasks (index finger tapping, simple reaction time and grip strength tasks). Following navigated rTMS, the amplitude of MEPs elicited from the contralateral (unstimulated) motor cortex was significantly increased, and was associated with an increase in ICF and a trend to decrease in ICI. In contrast, non-navigated rTMS elicited nonsignificant changes, most prominently ipsilateral to rTMS. Behaviorally, navigated rTMS significantly improved reaction time RT and pinch force with the hand ipsilateral to stimulation. Non-navigated rTMS lead to similar behavioral trends, although the effects did not reach significance. In summary, navigated rTMS leads to more robust modulation of the contralateral (unstimulated) hemisphere resulting in physiologic and behavioral effects. Our findings highlight the spatial specificity of inter-hemispheric TMS effects, illustrate the superiority of navigated rTMS for certain applications, and have implications for therapeutic applications of rTMS.

Perceptual learning of non-native speech contrast and functioning of the olivocochlear bundle

The purpose of this study was to investigate the relationship between perceptual learning of non-native speech sounds and strength of feedback in the medial olivocochlear bundle (MOCB). Discrimination abilities of non-native speech sounds (Malayalam) from its native counterparts (Hindi) were monitored during 12 days of training. Contralateral inhibition of otoacoustic emissions were measured on the first and twelfth day of training. Results suggested that training significantly improved reaction time and accuracy of identification of non-native speech sounds. There was a significant positive correlation between the slope (linear) of identification scores and change in distortion product otoacoustic emission inhibition at 3000 Hz. Findings suggest that during perceptual learning feedback from the MOCB may fine tune the brain stem and/or cochlea. However, such a change, isolated to a narrow frequency region, represents a limited effect and needs further exploration to confirm and/or extend any generalization of findings.SumarioEl propósito de este estudio fue investigar la relación entre el aprendizaje perceptual de sonidos no nativos del lenguaje y la fuerza de la retroalimentación en el fascículo olivo-coclear medial (MOCD). Se monitoreó la capacidad de discriminación de sonidos no nativos del lenguaje (Mayayalam) con sus contrapartes nativas (Hindi) durante un entrenamiento de 12 días. Se midió la inhibición contralateral de las emisiones otoacústicas en el primero y el último día del entrenamiento. Los resultados sugieren que el entrenamiento mejoró significativamente el tiempo de reacción y la exactitud de identificación de los sonidos no nativos del lenguaje. Existió una correlación significativamente positiva entre la pendiente (lineal) de los puntajes de identificación y el cambio en la inhibición de las emisiones otoacústicas por productos de distorsión en 3000 Hz. Los hallazgos sugieren que durante el aprendizaje perceptual, la retroalimentación del MOCB puede afinar las funciones del tallo cerebral y/o la cóclea. Sin embargo, tal cambio, limitado a una región estrecha de frecuencia, representa un efecto limitado y requiere de una exploración ulterior para confirmar y/o extender cualquier generalización sobre los hallazgos.

The effects of acute and prolonged CRAM supplementation on reaction time and subjective measures of focus and alertness in healthy college students

BackgroundThe purpose of this study was to examine the effect of acute and prolonged (4-weeks) ingestion of a supplement designed to improve reaction time and subjective measures of alertness, energy, fatigue, and focus compared to placebo.MethodsNineteen physically-active subjects (17 men and 2 women) were randomly assigned to a group that either consumed a supplement (21.1 ± 0.6 years; body mass: 80.6 ± 9.4 kg) or placebo (21.3 ± 0.8 years; body mass: 83.4 ± 18.5 kg). During the initial testing session (T1), subjects were provided 1.5 g of the supplement (CRAM; α-glycerophosphocholine, choline bitartrate, phosphatidylserine, vitamins B3, B6, and B12, folic acid, L-tyrosine, anhydrous caffeine, acetyl-L-carnitine, and naringin) or a placebo (PL), and rested quietly for 10-minutes before completing a questionnaire on subjective feelings of energy, fatigue, alertness and focus (PRE). Subjects then performed a 4-minute quickness and reaction test followed by a 10-min bout of exhaustive exercise. The questionnaire and reaction testing sequence was then repeated (POST). Subjects reported back to the lab (T2) following 4-weeks of supplementation and repeated the testing sequence.ResultsReaction time significantly declined (p = 0.050) between PRE and POST at T1 in subjects consuming PL, while subjects under CRAM supplementation were able to maintain (p = 0.114) their performance. Significant performance declines were seen in both groups from PRE to POST at T2. Elevations in fatigue were seen for CRAM at both T1 and T2 (p = 0.001 and p = 0.000, respectively), but only at T2 for PL (p = 0.029). Subjects in CRAM maintained focus between PRE and POST during both T1 and T2 trials (p = 0.152 and p = 0.082, respectively), whereas significant declines in focus were observed between PRE and POST in PL at both trials (p = 0.037 and p = 0.014, respectively). No difference in alertness was seen at T1 between PRE and POST for CRAM (p = 0.083), but a significant decline was recorded at T2 (p = 0.005). Alertness was significantly lower at POST at both T1 and T2 for PL (p = 0.040 and p = 0.33, respectively). No differences in any of these subjective measures were seen between the groups at any time point.ConclusionResults indicate that acute ingestion of CRAM can maintain reaction time, and subjective feelings of focus and alertness to both visual and auditory stimuli in healthy college students following exhaustive exercise. However, some habituation may occur following 4-weeks of supplementation.

Ayurvedic approach for improving reaction time of attention deficit hyperactivity disorder affected children.

Attention deficit/hyperactivity disorder (ADHD) is a behavioral disorder of children. It is the most common neurological disorder of childhood. The present study was conducted to examine the increase in attention span in 43 ADHD-affected children treated with different approaches. The reaction time was measured using a Vernier chronoscope (electronic). Selected children of both sexes in the age-group of 6–16 years were divided into three groups. In group A, 17 patients received syrup Ayurvedic compound I; in group B, 14 patients were treated with syrup Ayurvedic compound I + Shirodhara with milk; and in group C, 12 patients received syrup Ayurvedic compound II (placebo). The dose of the drug was 1.0 ml/kg body weight and the duration of treatment was 3 months. Group B showed highly significant (P<.001) improvement in total reaction time, while in group C the change was statistically nonsignificant P > 0.10. It was found that while the drug and Shirodhara were both effective in improving the reaction time of ADHD-affected children, the drug combined with Shirodhara was superior to the drug used alone.

Conditioned effects of caffeine on performance in humans

There is limited evidence for the conditioning of stimulant-like drug effects to previously-neutral stimuli in humans. Two studies tested whether the facilitatory effects of caffeine on cognitive performance can be conditioned to the context of drug administration. In Experiment 1, sixteen participants were divided equally into two groups: one group (the “paired” group) received 250 mg caffeine in a novel beverage prior to completing two computerized performance tests; the other group (the “unpaired” group) received the same beverage without caffeine (i.e. placebo) before testing. After the performance tests, the unpaired group received the caffeinated drink, and the paired group received placebo in a different context from that in which testing had taken place. The performance tests comprised a test of simple reaction time to a visual stimulus and a test of logical reasoning (the semantic verification task). The procedure was repeated over four separate conditioning trials. On a subsequent fifth session, the test for a conditioned response, all participants received placebo before test. Simple reaction time was significantly reduced by caffeine over the four conditioning trials, and on the test for conditioned responding the paired group performed significantly faster than the unpaired group, indicating the development of a conditioned response. In Experiment 2, twelve participants attended four conditioning trials in which either 250 mg of caffeine (two sessions) or placebo (two sessions) were paired with two visually distinct environments. After completing the conditioning sessions, tests for conditional responding were conducted by administering placebo in both contexts. During the conditioning phase, caffeine significantly improved reaction time performance relative to placebo, and this advantage was maintained at test in the CS+ context when placebo was administered in both contexts. Therefore the facilitatory effects of caffeine on performance can be elicited, in the absence of drug, by previously-neutral contextual stimuli that have been paired with drug administration.

Risques d’importation des maladies infectieuses exotiques en France métropolitaine : détection, alerte et réponse

RESUMEDans le domaine des maladies infectieuses, l’Institut de veille sanitaire est chargé d’impulser et de coordonner l’anticipation et l’analyse des risques infectieux afin d’alerter l’autorité sanitaire et de lui fournir des éléments de réponse face à ces risques. Dans le domaine infectieux, la veille épidémiologique vise à détecter précocement les menaces sanitaires en captant des signaux d’alerte qui recouvrent les champs humain et animal. Les signaux étant nombreux et de qualité variable, une vérification est effectuée. L’évaluation du risque d’introduction et de diffusion d’un pathogène sur le territoire est ensuite effectuée au travers d’une expertise multidisciplinaire. Dans cet article nous illustrons à l’aide d’exemples, différents scenarii de détection, d’analyse de risque et de réponse concernant des phénomènes infectieux présents dans la zone intertropicale et potentiellement importables en France métropolitaine. Qu’il s’agisse d’agents peu connus car rarement identifiés en Métropole, ou d’agents émergents de novo, l’analyse et la réponse doivent rester flexibles et être ajustées en fonction des données épidémiologiques et de l’interaction entre l’agent, l’hôte et son environnement. Ces incertitudes nous amèneront à discuter des besoins en matière de surveillance, dans une optique d’amélioration de la réactivité et de l’expertise.

Comparing the Stimulant Effects of the H1-Antagonist Fexofenadine With 2 Psychostimulants, Modafinil and Methylphenidate

Although antihistamines are known for their sedative adverse effects, fexofenadine was previously shown to have stimulating effects. These stimulant effects were rather mild in magnitude and were only demonstrated in tasks with a high workload. The present study was set up to compare the magnitude of the stimulant effect of fexofenadine with those of 2 psychostimulants, modafinil and methylphenidate. Sixteen healthy volunteers (5 males and 11 females; mean age, 21.8 years) participated in a 4-way, placebo-controlled, crossover study. The effects of fexofenadine (360 mg), modafinil (200 mg), methylphenidate (20 mg), and placebo were compared in a critical tracking, divided attention, motor impulsivity, and vigilance task. In this study, no significant stimulant effects of fexofenadine were found in any of the tasks. Modafinil only improved reaction time in the vigilance task, whereas methylphenidate improved performance in the divided attention and vigilance tasks. In addition, performance after methylphenidate treatment was also better than after fexofenadine in the divided attention and vigilance tasks. From the results, it can be concluded that the stimulating effects of methylphenidate are confirmed, whereas the stimulating effects of fexofenadine were not demonstrated in this study. It is evident that the stimulating effects of fexofenadine, which were apparent in previous studies, are not of the same magnitude as the effects of known psychostimulants such as methylphenidate.

Effect of Acute Exercise on Cognitive Control Required during an Eriksen Flanker Task

This study aimed to determine how cognitive control, engaged in a task requiring selective inhibition, is affected by acute steady-state exercise. An adapted version of the Eriksen flanker task, involving three types of trials that varied according to their level of congruency (congruent trials, stimulus-incongruent trials, and response-incongruent trials) was performed during 2 periods of 20-min cycling at a carefully controlled intensity (50% of maximal aerobic power). The results indicated that moderate exercise improves reaction time (RT) performance on the Eriksen flanker task. This facilitating effect appeared to be neither dependent on the nature of the interference (stimulus level conflict vs. response level conflict) nor on the amount of cognitive control engaged in the task (congruent vs. incongruent trials). Distributional RT analyses did not highlight any sign of impairment in the efficiency of cognitive control.

Caffeine expectancies influence the subjective and behavioral effects of caffeine

This study investigated the independent and interactive effects of caffeine pharmacology and expected effects of caffeine on performance and subjective outcomes. Abstinent coffee drinkers (n = 60) consumed decaffeinated coffee with either 280 mg or 0 mg added caffeine. Caffeine dose was crossed with varying instructions that the coffee would either enhance or impair performance in a 2 x 2 factorial design. Performance, mood, caffeine withdrawal, and negative somatic effects were assessed. Relative to placebo, caffeine improved reaction time and accuracy on the rapid visual information processing task, a measure of vigilance. However, there was a significant dose by expectancy interaction that revealed that among participants given placebo coffee, "impair" instructions produced better performance than "enhance" instructions. Caffeine also improved psychomotor performance as indicated by a finger tapping task with no main effects of expectancy or interactions. Impair instructions produced greater reports of negative somatic effects than enhance instructions, but only when caffeine was administered. Manipulating the expected effects of caffeine altered the behavioral and subjective effects of caffeine. A significant dose by expectancy interaction revealed a somewhat paradoxical outcome in the placebo conditions whereby those told "impair" performed better than those told "enhance." This may reflect compensatory responding as has been observed in similar studies using alcohol (Fillmore et al. Psychopharmacology 115:383-388, 1994). Impair instructions led to greater negative somatic effects only when caffeine was administered supporting the active placebo hypothesis.

Early visual deprivation alters multisensory processing in peripersonal space

Multisensory peripersonal space develops in a maturational process that is thought to be influenced by early sensory experience. We investigated the role of vision in the effective development of audiotactile interactions in peripersonal space. Early blind (EB), late blind (LB) and sighted control (SC) participants were asked to lateralize auditory, tactile and audiotactile stimuli. The experiment was conducted with the hands uncrossed or crossed over the body midline in order to alter the relationship between personal and peripersonal spatial representations. First, we observed that the crossed posture results in a greater detrimental effect for tactile performance in sighted subjects but a greater deficit in auditory performance in early blind ones. This result is interpreted as evidence for a visually driven developmental process that automatically remaps tactile and proprioceptive spatial representation into an external framework. Second, we demonstrate that improved reaction times observed in the bimodal conditions in SC and LB exceeds that predicted by probability summation in both conditions of postures, indicating neural integration of different sensory information. In EB, nonlinear summation was obtained in the uncrossed but not in the crossed posture. We argue that the default use of an anatomically anchored reference system in EB prevents effective audiotactile interactions in the crossed posture due to the poorly aligned spatial coordinates of these two modalities in such conditions. Altogether, these results provide compelling evidence for the critical role of early vision in the development of multisensory perception and action control in peripersonal space.

P2 enhancement from auditory discrimination training is associated with improved reaction times

This study examined the effects of training in a pure tone discrimination task on relations between behavioral performance and the magnitude of auditory event-related potentials (ERPs). Participants performed both passive (listening) and active (detecting) oddball tasks in a pretest and two posttests (1 and 9 weeks after training). Training produced a long-term benefit in both perceptual sensitivity and reaction times (RT). Training enhanced the amplitude of the P2 ERP component to both standards and deviants at both early and delayed posttests. Importantly, P2 enhancement was strongly associated with discrimination RT, suggesting that experience facilitates rapid, preattentive access to perceptual representations. Training also elevated the mismatch negativity, possibly due to the strengthening of acoustic traces. Finally, training enhanced the amplitude of the P3 component to deviants across posttests, indicating a long-lasting effect of discrimination training on stimulus salience.

Double-Blind, Placebo-Controlled, Multiple-Ascending-Dose Study on the Pharmacodynamics of ABIO-08/01, a New CNS Drug with Potential Anxiolytic Activity

In a double-blind, placebo-controlled, multiple-ascending-dose study, the encephalotropic and psychotropic properties of ABIO-08/01, a new potentially anxiolytic and nootropic isoxazoline, were studied in 16 young healthy males. In a randomized nonbalanced phase 1 study, they received 3 oral drug doses (10, 20, 40 mg) and placebo for 7 days (washout period 8 days). EEG mapping and psychometry were carried out at hours 0, 1, 6 of day 1 (acute effect) and day 5 (subacute and superimposed effects). MANOVA/ Hotelling T² test demonstrated significant central effects of ABIO-08/01 versus placebo after acute, subacute and superimposed administration of all doses in the resting, vigilance-controlled and eyes-open EEG. Univariate analysis revealed activating patterns in the resting EEG (40 mg > 20 mg > 10 mg), and sedative patterns in the eyes-open EEG (10 mg > 20 mg > 40 mg). In the vigilance-controlled EEG, 40 mg of ABIO-08/01 induced activating patterns, whereas 10 mg induced sedative patterns. Concerning psychometry, ABIO-08/01 improved concentration (40 mg > 20 mg > 10 mg; activating effect) and deteriorated well-being (10 mg > 20 mg > 40 mg; sedative effect). Ten milligrams also improved reaction time performance and psychomotor activity. ABIO-08/01 is well-tolerated and is of interest in anxiety disorders.