Stereopsis and Response Times between Collegiate Table Tennis Athletes and Non-Athletes

Table tennis athletes and non-athletes potentially differ in stereopsis and eye–hand response times (RT), but whether stereopsis correlates with response time has scarcely been discussed. We aimed to compare stereopsis and RT between collegiate table tennis athletes and non-athletes and to examine the correlation between stereopsis and RT. From December 2016 to October 2019, table tennis athletes (n = 80) and non-athletes (n = 56) were recruited. Stereopsis was measured in four modes (A25, A50, R25, R50: approaching and receding directions at 25 mm/s or 50 mm/s). RT was measured with simple and choice tasks at zero, shoulder, and random distance. For stereopsis, the judged deviations were smaller during the approaching phases. Men had smaller A25 than women (p =0.012), whereas table tennis athletes showed smaller R25 and A50 than non-athletes (p = 0.03, 0.01, respectively). RT increased from simple to choice conditions and from zero to random, followed by shoulder distance. Men were significantly faster than women in choice tasks (p < 0.01). Table tennis athletes performed better in RT than the non-athletes (p < 0.05). No correlation was observed between stereopsis and RT (r = −0.01 to 0.12). In conclusion, athletes from table tennis sports showed better stereopsis and RT than non-athletes. Men had better stereopsis and RT than women. There was no correlation between stereopsis and RT.

Automatic inhibition of habitual response associated with a non-target object while performing goal-directed actions

This study is devoted to investigating mechanisms that inhibit habituated response associated with affordance of a non-target while executing action directed to a target. In four experiments, a paradigm was used that required a rapid left- or right-hand response according to the direction of the target arrow presented simultaneously or in close temporal proximity to a non-target whose handle position afforded grasping with the left or right hand. In general, responding was decelerated and more erroneous when the handle position was compatible with the responding hand. This effect of response inhibition was removed when the delay between the non-target offset and target onset was longer than 200 ms, and reversed into response facilitation when the target onset was delayed for 400–600 ms. The study suggests that processes that control withholding habitual response associated with affordance of a non-target utilise response inhibition mechanisms overlapping with those involved in behavioural control of the stop-signal task. This response inhibition is triggered automatically and directly by affordance of a non-target without preceding response excitation associated with this affordance cue.

Taking a wider look at multitasking through a triple-task

In the past, multitasking research was dominated by different dual-task paradigms. Although dual tasks allow for large variations - simultaneous processing, sequential processing, or task-switching - this variability is still far from complex everyday multitasking affording situations. This study aimed to examine the effects of three two-choice simultaneous tasks and to compare them with historic dual-tasks and discuss fitting models. The triple-task consisted of two visual tasks and one auditory task. Crucially, participants had to switch the stimulus-response (S-R) pairing of both visual tasks in half of the session from standard S-R pairings (e.g. location task and hand response) to non-standard S-R pairings (e.g. color task and feet response) or vice-versa. Our results showed that response times in the triple-task were up to two times higher than in dual-tasks in comparable studies. Additionally, both visual tasks were responded to similarly fast although they consisted of standard and non-standard feature pairings. It also seemed to be easier for participants to switch the S-R pairings concerning their ‘hand’-response from non-standard S-R pairings to standard S-R pairings compared to switching from standard to non-standard pairings. We assume according to TEC, memory files were formed faster in the latter, which caused interference after switching the S-R pairings. Finally, our study showed that current multitasking research is limited in ecological validity by focussing predominantly on dual-tasks and would benefit from research with more complex task settings beyond dual-tasks.

Cortical and subcortical functional specificity associated with response inhibition.

The existence of specific neuronal systems dedicated for response inhibition, as opposed tomore general action updating, is controversial. This pre-registered study employed a taskinvolving both inhibitory and non-inhibitory action updating in combination with functionalmagnetic resonance imaging to test the specificity of responses under different updatingconditions, including the cessation of actions. Cortical regions of activity were found to becommon to multiple forms of action updating. However, functional specificity duringresponse inhibition was observed in the anterior right Inferior Frontal Gyrus. In addition, wedeveloped an exploratory contrast method which suggested this specificity continueddownstream to subcortical loci, with right hemisphere activity largely supporting responseinhibition, and left hemisphere activity associated with right hand response execution. Thepattern of activations supports putative models of subcortical pathways and extends themthrough the demonstration of lateralisation.

Delays in Manual Reaching Are Associated with Impaired Functional Abilities in Early Dementia Patients

Background/Aims: Recent evidence shows that early dementia patients have deficits in manual reaching tasks. It is important to understand the impact of these functional disabilities on their quality of life. The aim of this study was to investigate if there is an association between manual reaching and measures of (instrumental) activities of daily living (IADL) in a group of patients with cognitive complaints. Methods: The manual reaching performance of 27 patients was assessed in detail with eye and hand tracking devices. Patients were divided into three groups based on self-reported loss of IADL function. Parameters describing hand response and movement times were compared between groups. Results: Patients with loss of IADL function in ≥1 domain had delayed hand response and hand movement times towards visible targets compared to patients with no loss of IADL function. Conclusion: Delays in manual reaching movements are related to the degree of loss of IADL function in early dementia patients.

Platelet response heterogeneity in thrombus formation

SummaryVascular injury leads to formation of a structured thrombus as a consequence of platelet activation and aggregation, thrombin and fibrin formation, and trapping of leukocytes and red cells. This review summarises current evidence for heterogeneity of platelet responses and functions in the thrombus-forming process. Environmental factors contribute to response heterogeneity, as the platelets in a thrombus adhere to different substrates, and sense specific (ant)agonists and rheological conditions. Contraction of platelets and interaction with fibrin and other blood cells cause further response variation. On the other hand, response heterogeneity can also be due to intrinsic differences between platelets in age and in receptor and signalling proteins. As a result, at least three subpopulations of platelets are formed in a thrombus: aggregating platelets with (reversible) integrin activation, procoagulant (coated) platelets exposing phosphatidylserine and binding coagulation factors, and contracting platelets with cell-cell contacts. This recognition of thrombus heterogeneity has implications for the use and development of antiplatelet medication.

Either or neither, but not both: locating the effects of masked primes

Execution of a response that has been primed by a backward-masked stimulus is inhibited (negative compatibility effect; NCE). Three experiments investigated the locus of this inhibition. Masked primes (left- or right-pointing arrows) were followed either by an arrow or a circle target. Arrow targets always required a left- or right-hand response, but the experiments differed in the response required to circles: press neither, either or both response keys (i.e. nogo, free choice and bimanual, respectively). Arrow targets showed the usual NCEs. Circle targets showed NCEs in the form of a response bias away from the primed response in the nogo and free-choice tasks; primes and targets differed on these trials, ruling out a perceptual explanation of the NCE. The bimanual task showed no such bias, suggesting that the NCE is located at a level of abstract response codes rather than specific muscle commands.

Further Evidence that the SNARC Effect is Processed Along a Dual-Route Architecture

In a binary response setting, it has been frequently observed that small numbers are reacted to faster with the left hand and large numbers with the right hand (i. e., the SNARC-effect) which reflects the spatial left-right orientation of the mental number line ( Dehaene, Bossini, & Giraux, 1993 ). In line with the work of Keus and Schwarz (in press ), we investigated the locus of the conflict in the SNARC effect in a parity judgment task with the Arabic numerals 1, 2, 8, or 9. Differences between compatible (left-hand response to 1 or 2 and right-hand response to 8 and 9) and incompatible SNARC conditions (left-hand response to 8 or 9 and right-hand response to 1 or 2) were observed in the lateralized readiness potential (LRP) but not in the peak latency of the P300. In accordance with Keus and colleagues ( Keus, Jenks, & Schwarz, 2005 ), we argue that the locus of the conflict is situated at intermediate response-related stages. However, instead of adopting a single-route processing architecture, a dual route account is proposed as the underlying processing architecture explaining the SNARC effect.