Rapid error correction during human arm movements: evidence for central monitoring

Studies were made of rapid error correction movements in eight subjects performing a visually guided tracking task involving flexion-extension movements about the elbow. Subjects were required to minimize reaction times in this two-choice task. Errors in initial movement direction occurred in about 3% of the trials. Error correction times (time from initiation to reversal of movement in incorrect direction) ranged from 30-150 ms. The first sing of correction of the error movement was a suppression of the electromyographic (EMG) activity in the muscle producing the error movement. This suppression started as early as 20-40 ms after the initiation of the error-related EMG activity and as much as 50 ms before any overt sign of limb movement. The correction of the error movement was also accompanied by an increase in the drive to the muscle which moved the arm in the correct direction. This increased activity always occurred after the initiation of the error movement. it is concluded that the first step in the error correction, suppression of drive to the muscle producing the error movement, cannot be based on information from the moving limb. It is thus suggested that this earliest response to the error movement is based on central monitoring of the commands for movement.     

Temporal and spatial factors reflecting performance improvement during learning three-ball cascade juggling

Beek and van Santvoord [Beek, P. J., & van Santvoord, A. A. M. (1992). Journal of Motor Behavior, 24, 85-94] proposed a three-stage model of learning to juggle based on group analyses of temporal measures. Here, we examined in detail how the temporal and spatial features of juggling evolved in eight individual participants progressing from the second to the third stage of learning. During the second stage, the dwell ratio, defined as the ratio of the time that the juggler holds a ball between catch and toss and the hand cycle time (HCT), was stable when it was about 0.83. The subjects with a dwell ratio near this value and controlled throws exhibited stable juggling, whereas the subjects with a dwell ratio of 0.80 or smaller exhibited unstable juggling. Compared to the former group, the latter group had a longer time from the throw of a ball to the arrival at its zenith (TZ), and a shorter time between the arrival of an airborne ball at its zenith and the subsequent throw (IZR). The latter group also exhibited larger variability in the dwell ratio and IZR. With practice, the subjects appropriated, on average, the duration of TZ and IZR to the dwell ratio and improved the ability to accurately throw balls by changing the motions of the limb segments involved. Although these changes helped to stabilize the performance during the second stage, the variability problem was not sufficiently resolved. Only two out of eight subjects passed on to the third stage by the last (10th) Session. They achieved small variability in IZR, dwell ratio, and flight paths of the ball while juggling with short HCTs and small dwell ratios. These results suggest that the reduction of variability in these variables was essential to pass on to the third stage.     

Effects of active student response during error correction on the acquisition and maintenance of geography facts by elementary students with learning disabilities

An alternating treatments design was used to compare the effects of Active Student Response (ASR) error correction and No Response (NR) error correction during instruction of the capitals of states and countries. Three students with learning disabilities were provided one-to-one daily instruction on four sets of 14 unknown capitals (7 ASR capitals and 7 NR capitals). Student errors during instruction on ASR capitals were immediately followed by the teacher stating the capital and the student repeating it (an active student response). Errors on NR capitals were immediately followed by the teacher stating the capital while the student visually attended to a geography card with the correct capital handwritten on it (an on-task response). During instruction each of the three students correctly stated more capitals taught with ASR instruction than he or she stated with NR error correction. Results of same-day and next-day tests show that all three students learned more capitals with ASR error correction than with NR error correction The students also correctly stated more ASR error correction capitals on 1-week maintenance tests.     

Synchronizing movements with the metronome: nonlinear error correction and unstable periodic orbits.

The control of human hand movements is investigated in a simple synchronization task. We propose and analyze a stochastic model based on nonlinear error correction; a mechanism which implies the existence of unstable periodic orbits. This prediction is tested in an experiment with human subjects. We find that our experimental data are in good agreement with numerical simulations of our theoretical model. These results suggest that feedback control of the human motor systems shows nonlinear behavior.     

The correction for attenuation due to measurement error: clarifying concepts and creating confidence sets

The correction for attenuation due to measurement error (CAME) has received many historical criticisms, most of which can be traced to the limited ability to use CAME inferentially. Past attempts to determine confidence intervals for CAME are summarized and their limitations discussed. The author suggests that inference requires confidence sets that demarcate those population parameters likely to have produced an obtained value--rather than indicating the samples likely to be produced by a given population--and that most researchers tend to confuse these 2 types of confidence sets. Three different Monte-Carlo methods are presented, each offering a different way of examining confidence sets under the new conceptualization. Exploring the implications of these approaches for CAME suggests potential consequences for other statistics.     

Timing and aging: slowing of fastest regular tapping rate with preserved timing error detection and correction

This study assessed motor limits of regular tapping, timing error detection, and correction in 60 participants aged from 19 to 98 years. Rate limitations on motor production were estimated from the average inter-tap interval when tapping as fast as possible for 30 s. Timing error detection required participants to judge whether a sound sequence presented at a slow, intermediate, or fast speed contained an irregularity because of phase shift. This was performed with or without synchronizing to the sounds. On the basis of the just-detectable positive phase shift (JND), participants synchronized with sequences containing phase shifts that were subliminal, just detectable or supraliminal. On average, JNDs were 9% of the inter-onset interval and by and large were not affected by synchronization tapping. Speed of error correction was estimated from the number of tones to return within 20% of the preshift synchronization error. Consistent with previous findings of motor slowing with aging, the fastest inter-tap interval increased with age. However, there was no age-related decline in JNDs or speed of error correction, both of which reflect predictive abilities for intervals within the motor repertoire of human adults. These results point towards intact timing error processing up to an advanced age. In assessing timing abilities in the brain of older adults, it is important to differentiate between motor slowing and its impact on rhythmic behavior (e.g., walking pace) from anticipatory mechanisms ('what to expect when') and how these are used to adjust the timing of actions ('what to do when').     

Effects of active student response during error correction on the acquisition, maintenance, and generalization of science vocabulary by elementary students: A systematic replication

We compared active student response (ASR) error correction and no-response (NR) error correction while teaching science terms to 5 elementary students. When a student erred on ASR terms, the teacher modeled the definition and the student repeated it. When a student erred on NR terms, the teacher modeled the definition while the student looked at the vocabulary card. ASR error correction was superior on each of the study's seven dependent variables.     

The relationship between depressive symptoms and error monitoring during response switching

Heightened sensitivity to failure and negative information is thought to be an important maintenance mechanism for symptoms of depression. However, the specific neural and behavioral correlates of the abnormal reactions to errors associated with depression are not yet well understood. The present study was designed to shed new light on this issue by examining how depressive symptoms relate to error monitoring in the context of different task demands. We used a modified flanker task in which the stimulus–response (S–R) mappings were reversed between blocks, differentiating relatively easy nonreversal blocks from the more-demanding S–R reversal blocks. Undergraduates performed this task and then completed a self-report measure of anhedonic depression. The results revealed that depressive symptoms were related to poorer posterror accuracy in the more-difficult S–R reversal blocks, but not in the easier nonreversal blocks. Event-related brain potentials (ERPs) within a subsample of these participants further indicated that depressive symptoms were associated with reduced error positivity (Pe) amplitudes in both block types, suggesting that depressive symptoms were related to reduced attention allocation to errors across the easy and hard blocks. Finally, brain–behavior correlations indicated that highly depressed individuals failed to display a relationship between Pe amplitude and posterror accuracy in the S–R reversal blocks, a relationship that was intact in the low-depression group. Together, these results suggest that task demands play a critical role in the emergence of error-monitoring abnormalities in depression.     

The stability of binocular rivalry during spaced and massed viewing

Attention, Perception, & Psychophysics - The purpose of the study was consideration of the stability of binocular rivalry rates during extended periods of spaced and massed viewing by untrained...     

Comparison of simultaneous prompting with and without error correction in teaching science vocabulary words to high school students with mild disabilities

This study compared the effectiveness and efficiency of simultaneous prompting with and without error correction during daily probe sessions in teaching science vocabulary words. The teacher presented the vocabulary word definitions as instructive feedback during training sessions. Five 16–17 year old students with disabilities participated in an adapted alternating treatments design that evaluated the simultaneous prompting strategy, error correction and instructive feedback. Instruction occurred in a group format using choral responding. The results indicate that (a) all students learned to read the vocabulary words, (b) simultaneous prompting with error correction was slightly more efficient for three of the five subjects in learning the targeted words, and four of the five students made fewer errors in this condition, (c) all students preferred simultaneous prompting with error correction over simultaneous prompting without error correction, (d) words mastered in both conditions generalized equally, (e) there were minimal differences between the two conditions in the collected maintenance data, and (e) students experienced only minimal improvement in their ability to define vocabulary words (instructive feedback). Discussion focuses on issues for further research and implications for instructional practice with simultaneous prompting, error correction and instructive feedback.     

Orthographic error monitoring in old age: lexical and sublexical availability during perception and production

Previous research suggests that older adults suffer declines in producing accurate spellings but retain the ability to accurately detect misspellings. The preservation of perception in the face of impaired production has been used to support a model of aging in which age impairs access to linguistic representations under specific circumstances, while representations themselves remain intact. The current research tests two predictions of this Transmission Deficit Hypothesis (TDH): first, that the differential effect of age on perception and production occurs when tasks are equated on response requirements and underlying representations, and second, that both word and spelling frequency interact to determine the effect of age on performance. Results of two error monitoring tasks supported the predictions of the TDH, demonstrating age-related production impairments that interacted with both word and spelling frequency, but no impairment of older adults' spelling perception, even for low frequency words or spellings.     

Methylphenidate slows reactions of children with attention deficit disorder during and after an error

A Sternberg memory search task was administered under placebo and methylphenidate to 42 children with cross-situational attention deficit disorder (ADD), 31 children with cross-situational ADD plus oppositional features, and 25 patients with marginal ADD. Overall, stimulant medication enhanced accuracy and speed. In addition, patients reacted faster on correct responses not preceded by an error than on errors (especially false alarms) or on correct responses following an error. The slowness during error reactions may reflect decreased confidence or confusion during stimulus classification. This uncertainty may also lead subjects to respond with greater caution, hence more slowly, on correct responses following errors. Notably, methylphenidate increased the slowing of reactions on error trials as well as on correct reactions following an error. Stimulant medication may augment subjects' persistence when they are uncertain or confused, thereby heightening caution and promoting accuracy on succeeding trials. Consistent with previous reports of the generality of enhancement of performance by stimulant medication, the impact of methylphenidate was comparable for the three subtypes of ADD studied.Jaine Strauss is at Macalester College.This research was supported by National Institute of Mental Health Grants MH32103 and MH38118. We thank Rachel Avery, Christine Carriuolo, Lawrence Ota, the late Helen Pollock, and the University of Rochester's Strong Memorial Hospital Pharmacy for their assistance.     

Differential stability and individual growth trajectories of big five and affective traits during young adulthood

Big Five and affective traits were measured at three assessments when participants were on average 18, 21, and 24 years old. Rank-order stability analyses revealed that stability correlations tended to be higher across the second compared to the first retest interval; however, affective traits consistently were less stable than the Big Five. Median stability coefficients for the Big Five increased from .62 (Time 1 vs. Time 2) to .70 (Time 2 to Time 3); parallel increases also were observed for measures of negative affectivity (median rs=.49 and .55, respectively) and positive affectivity (median rs=.48 and .57, respectively). Growth curve analyses revealed significant change on each of the Big Five and affective traits, although many of the scales also showed significant variability in individual trajectories. Thus, rank-order stability is increasing for a range of personality traits, although there also is significant variability in change trajectories during young adulthood.     

The stability of self-concept during adolescence and early adulthood: a six-year follow-up study

The stability and gender differences of self-concept during adolescence and early adulthood were studied in 894 randomly selected Finnish subjects using the shortened version of the Coopersmith (1967) Self-Esteem Inventory. There were no differences between the men and women in the total score for self-concept. In early adulthood, men scored higher than women on general self-esteem, and women scored higher on the home-parents factor in each developmental period from pre-adolescence to adulthood. The stability of self-concept, as well as its different components, was rather high. General self-esteem showed the highest predictive value for the total score 6 years later.     

Frontal electroencephalogram alpha asymmetry during sleep: stability and its relation to affective style

Electroencephalogram (EEG) alpha (8-12 Hz) asymmetries were collected from the mid-frontal and central regions during presleep wakefulness and Stage 1, Stage 2, and rapid eye movement (REM) sleep in 11 healthy right-handed participants who were free of psychiatric, neurological, and sleep problems. The authors found significant correlations between presleep wakefulness and different stages of sleep in the frontal, but not central, EEG alpha asymmetry measure. The strongest correlation was between presleep waking and REM sleep, replicating and extending relation earlier work to a normal population. The high degree of association between presleep waking and REM sleep may be a result of high cortical activation common to these states and may reflect a predisposition to different styles of emotional reactivity.     

Turning social identity threat into challenge: Status stability and cardiovascular reactivity during inter-group competition

The current research examined the occurrence of threat and challenge in low and high status groups resulting from the stability of inter-group status differences during an inter-group competition. It was hypothesized that members of low status groups are relatively threatened when status differences are stable, but that this threat turns into a challenge when status differences become unstable. By contrast, unstable status relations were predicted to lead to threat in members of high status groups. Participants (N = 40) were categorized in minimal groups. Inter-group status differences, and the stability of these differences, were manipulated by providing feedback on three group tasks. During these tasks cardiovascular threat and challenge responses were measured following the biopsychosocial model [BPS; Blascovich, J., & Tomaka, J. (1996). The biopsychosocial model of arousal regulation. In M. Zanna (Ed.), Advances in experimental social psychology (Vol. 28, pp. 1-51). New York: Academic Press]. Results were in line with expectations and are discussed in terms of the BPS model and social identity theory.     

A computational model of visual stability and change detection during eye movements in real-world scenes

Visual cognition and change detection critically depend on attention and gaze. A central question is the exact involvement of attention in change detection. This paper proposes a detailed computational model to illuminate the nature of visual stability and change detection during eye movements. Consistent with experimental findings the model predicts that change detection at the saccade endpoint is relatively easy. According to our model the planning of an eye movement provides an enhanced sensory processing of an object at the saccade target. This facilitates the memorization of that object. A comparison of the memorized target template with the representation after saccade allows for change detection. We hypothesize that the spatial reentry signal that emerges from planning an eye movement could be a crucial neural basis of visual stability.     

Visual stability with goal-directed eye and arm movements toward a target displaced during saccadic suppression

This experiment tested whether the perceived stability of the environment is altered when there is a combination of eye and visually open-loop hand movements toward a target displaced during the eye movements, i.e., during saccadic suppression. Visual-target eccentricity randomly decreased or increased during eye movements and subjects reported whether they perceived a target displacement or not, and if so, the direction of the displacement. Three experimental conditions, involving different combinations of eye and arm movements, were tested: (a) eye movements only; (b) simultaneous eye and rapid arm movements toward the target; and (c) simultaneous eye and arm movements with a restraint blocking the arm as soon as the hand left the starting position. The perceptual threshold of target displacements resulting in an increased target eccentricity was greater when subjects combined eye and arm movements toward the target object, specially for the no-restraint condition. Subjects corrected most of their arm trajectory toward the displaced target despite the short movement times (average MT = 189 ms). After the movements, the null error feedback of the hand's final position presumably overlapped the retino-oculomotor signal error and could be responsible for the deficient perception of target displacements. Thus, subjects interpreted the terminal hand positions as being within the range of the endpoint variability associated with the production of rapid arm movements rather than as a change of the environment. These results suggest that a natural strategy adopted for processing spatial information, especially in a competing situation, could favour a constancy tendency, avoiding systematic perception of a change of environment for any noise or variability at the central or peripheral levels.