Does finger sense predict addition performance?

The impact of fingers on numerical and mathematical cognition has received a great deal of attention recently. However, the precise role that fingers play in numerical cognition is unknown. The current study explores the relationship between finger sense, arithmetic and general cognitive ability. Seventy-six children between the ages of 5 and 12 participated in the study. The results of stepwise multiple regression analyses demonstrated that while general cognitive ability including language processing was a predictor of addition performance, finger sense was not. The impact of age on the relationship between finger sense, and addition was further examined. The participants were separated into two groups based on age. The results showed that finger gnosia score impacted addition performance in the older group but not the younger group. These results appear to support the hypothesis that fingers provide a scaffold for calculation and that if that scaffold is not properly built, it has continued differential consequences to mathematical cognition.     

How do we convert a number into a finger trajectory?

How do we understand two-digit numbers such as 42? Models of multi-digit number comprehension differ widely. Some postulate that the decades and units digits are processed separately and possibly serially. Others hypothesize a holistic process which maps the entire 2-digit string onto a magnitude, represented as a position on a number line. In educated adults, the number line is thought to be linear, but the “number sense” hypothesis proposes that a logarithmic scale underlies our intuitions of number size, and that this compressive representation may still be dormant in the adult brain. We investigated these issues by asking adults to point to the location of two-digit numbers on a number line while their finger location was continuously monitored. Finger trajectories revealed a linear scale, yet with a transient logarithmic effect suggesting the activation of a compressive and holistic quantity representation. Units and decades digits were processed in parallel, without any difference in left-to-right vs. right-to-left readers. The late part of the trajectory was influenced by spatial reference points placed at the left end, middle, and right end of the line. Altogether, finger trajectory analysis provides a precise cognitive decomposition of the sequence of stages used in converting a number to a quantity and then a position.     

Response–effect compatibility of finger–numeral configurations in arithmetical context

Research in experimental economics suggests that decision making in strategic interactions is often guided by a concern for fairness. However, experimental economics studies routinely place participants of equal social status and no prior social history in anonymous interactions, a context that would tend to foster the adoption of an egalitarian fairness norm. Extensive research in anthropology (Fiske, 1991) and psychology (Bugental, 2000) suggests that social norms, including fairness norms, are relationship-specific, raising doubts about whether the concern for egalitarian fairness observed in the experimental economics literature would generalize to a wider range of social relations. In this paper we focus on an alternative social norm characteristic of hierarchical relationships: noblesse oblige—the obligation of high-ranking individuals to act honorably and beneficently towards subordinates. In a series of five experiments, we show that the norm of noblesse oblige predicts tolerance of free riding better than individual self-interest does.     

What effect can rhythmic finger tapping have on the phonological similarity effect?

The effects of rhythmic finger tapping on the phonological similarity effect were investigated in two experiments. In both, subjects were tested for serial recall of visually presented letter sequences that were either phonologically similar or dissimilar. The letter sequences had to be remembered under three tapping conditions: right-hand tapping, left-hand tapping, and a no-tapping control. Experiment 1 showed clear phonological similarity effects in both the control and the left-hand tapping conditions, but not in the right-hand tapping condition, when recall responses were written with the right hand. When the number of tapping practice trials was fixed at two and recall was vocal in Experiment 2, the phonological similarity effect was eliminated in both the right-hand and the left-hand tapping conditions. These results suggest that some form of speech motor programs played an important role in serial recall.     

Extensive occupational finger use delays age effects in tactileperception—an ERP study

Tactile expertise, resulting from extensive use of hands, has previously been shown to improve tactile perception in blind people and musicians and to be associated with changes in the central processing of tactile information. This study investigated whether expertise, due to precise and deliberate use of the fingers at work, relates to improved tactile perception and whether this expertise interacts with age. A tactile pattern and a frequency discrimination task were conducted while ERPs were measured in experts and nonexperts of two age groups within middle adulthood. Independently of age, accuracy was better in experts than in nonexperts in both tasks. Somatosensory N70 amplitudes were larger with increasing age and for experts than for nonexperts. P100 amplitudes were smaller in experts than in nonexperts in the frequency discrimination task. In the pattern discrimination task, P300 difference wave amplitude was reduced in experts and late middle-aged adults. In the frequency discrimination task, P300 was more equally distributed in late middle-aged adults. We conclude that extensive, dexterous manual work leads to acquisition of tactile expertise and that this expertise might delay, but not counteract, age effects on tactile perception. Comparable neurophysiological changes induced by age and expertise presumably have different underlying mechanisms. Enlarged somatosensory N70 amplitudes might result from reduced inhibition in older adults but from enhanced, specific excitability of the somatosensory cortex in experts. Regarding P300, smaller amplitudes might indicate fewer available resources in older adults and, by contrast, a reduced need to engage as much cognitive effort to the task in experts.     

Laterality of repetitive finger movement performance and clinical features of Parkinson’s disease

Impairments in acoustically cued repetitive finger movement often emerge at rates near to and above 2 Hz in persons with Parkinson’s Disease (PD) in which some patients move faster (hastening) and others move slower (bradykinetic). The clinical features impacting this differential performance of repetitive finger movement remain unknown. The purpose of this study was to compare repetitive finger movement performance between the more and less affected side, and the difference in clinical ratings among performance groups. Forty-one participants diagnosed with idiopathic PD completed an acoustically cued repetitive finger movement task while “on” medication. Eighteen participants moved faster, 10 moved slower, and 13 were able to maintain the appropriate rate at rates above 2 Hz. Clinical measures of laterality, disease severity, and the UPDRS were obtained. There were no significant differences between the more and less affected sides regardless of performance group. Comparison of disease severity, tremor, and rigidity among performance groups revealed no significant differences. Comparison of posture and postural instability scores revealed that the participants that demonstrated hastening had worse posture and postural instability scores. Consideration of movement rate during the clinical evaluation of repetitive finger movement may provide additional insight into varying disease features in persons with PD.     

Same-hand and different-hand finger pairings in two-choice reaction time: presence or absence of response competition?

Several two-choice reaction time experiments have compared conditions in which the two possible responses were from the same hand (same-hand pairing) or from different hands (different-hand pairing). Studies that used only the two relevant fingers on response keys reported shorter reaction times for the different-hand pairing. In other studies, two additional but irrelevant fingers were also in contact with response keys. These fingers were irrelevant in the sense that they never were required to respond. With this procedure, equivalent reaction times were found between same-hand and different-hand pairings. Reeve and Proctor (1988) recently have argued that using only two fingers results in response competition between the two fingers from the same hand, yielding shorter reaction times for the different-hand pairing condition. In contrast, when four fingers are placed on response keys, response competition should be absent for both the same-hand and the different-hand pairing conditions, resulting in equivalent reaction times. In the present work, reaction times associated with the same-hand pairing condition remained unchanged, irrespective of the number of fingers positioned on keys. In the different-hand pairing condition, reaction times were found to be longer when four fingers were used than when only two fingers rested on response keys. Thus, when four fingers are placed on keys, response competition appears to be present rather than absent. Other results showed that the response competition found in the different-hand pairing condition decreases with practice.     

Assessing heterogeneity in meta-analysis: Q statistic or I2 index?

In meta-analysis, the usual way of assessing whether a set of single studies is homogeneous is by means of the Q test. However, the Q test only informs meta-analysts about the presence versus the absence of heterogeneity, but it does not report on the extent of such heterogeneity. Recently, the I(2) index has been proposed to quantify the degree of heterogeneity in a meta-analysis. In this article, the performances of the Q test and the confidence interval around the I(2) index are compared by means of a Monte Carlo simulation. The results show the utility of the I(2) index as a complement to the Q test, although it has the same problems of power with a small number of studies.     

Exner's Four Square: useful index in appraisal of learning disability?

Rorschach protocols, focusing on Exner's Four Square, were obtained for 14 boys who had been referred for a second opinion following an initial diagnosis as learning disabled. The findings indicated wide diversity, suggesting that a significant proportion of students manifest fundamental problems which are not essentially cognitive in nature. For these students, traditional psychoeducational decisions may be inappropriate and unproductive.     

Bias-corrected estimation of the Rudas–Clogg–Lindsay mixture index of fit

Rudas, Clogg, and Lindsay (1994, J. R Stat Soc. Ser. B, 56, 623) introduced the so-called mixture index of fit, also known as pi-star (π*), for quantifying the goodness of fit of a model. It is the lowest proportion of ‘contamination’ which, if removed from the population or from the sample, makes the fit of the model perfect. The mixture index of fit has been widely used in psychometric studies. We show that the asymptotic confidence limits proposed by Rudas et al. (1994, J. R Stat Soc. Ser. B, 56, 623) as well as the jackknife confidence interval by Dayton ( 2003 , Br. J. Math. Stat. Psychol., 56, 1) perform poorly, and propose a new bias-corrected point estimate, a bootstrap test and confidence limits for pi-star. The proposed confidence limits have coverage probability much closer to the nominal level than the other methods do. We illustrate the usefulness of the proposed method in practice by presenting some practical applications to log-linear models for contingency tables.     

Can pupillometry index auditory attentional capture in contexts of active visual processing?

The rare presentation of a sound that deviates from the auditory background tends to capture attention, which is known to impede cognitive functioning. Such disruption is usually measured using performance on a concurrent visual task. Growing evidence recently showed that the pupillary dilation response (PDR) could index the attentional response triggered by a deviant sound. Given that the pupil diameter is sensitive to several vision-related factors, it is unclear whether the PDR could serve to study attentional capture in such contexts. Hence, the present study aimed at verifying whether the PDR can be used as a proxy for auditory attentional capture while a visual serial recall task (Experiment 1) or a reading comprehension task (Experiment 2) – respectively producing changes in luminance and gaze position – is being performed. Results showed that presenting a deviant sound within steady-state standard sounds elicited larger PDRs than a standard sound. Moreover, the magnitude of these PDRs was positively related to the amount of performance disruption produced by deviant sounds in Experiment 1. Performance remained unaffected by the deviants in Experiment 2, thereby implying that the PDR may be a more sensitive attention-capture index than behavioural measures. These results suggest that the PDR can be used to assess attentional capture by a deviant sound in contexts where the pupil diameter can be modulated by the visual environment.