Auditory dominance in temporal processing: New evidence from synchronization with simultaneous visual and auditory sequences.

Evidence that audition dominates vision in temporal processing has come from perceptual judgment tasks. This study shows that this auditory dominance extends to the largely subconscious processes involved in sensorimotor coordination. Participants tapped their finger in synchrony with auditory and visual sequences containing an event onset shift (EOS), expected to elicit an involuntary phase correction response (PCR), and also tried to detect the EOS. Sequences were presented in unimodal and bimodal conditions, including one in which auditory and visual EOSs of opposite sign coincided. Unimodal results showed greater variability of taps, smaller PCRs, and poorer EOS detection in vision than in audition. In bimodal conditions, variability of taps was similar to that for unimodal auditory sequences, and PCRs depended more on auditory than on visual information, even though attention was always focused on the visual sequences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

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'). (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Phase correction, phase resetting, and phase shifts after subliminal timing perturbations in sensorimotor synchronization.

Recent studies of synchronized finger tapping have shown that perceptually subliminal phase shifts in an auditory sequence are rapidly compensated for in the motor activity (B. H. Repp, 2000a). Experiment 1 used a continuation-tapping task to confirm that this compensation is indeed a phase correction, not an adjustment of the central timekeeper period. Experiments 2–5 revealed that this phase correction occurs even when there is no ordinary sensorimotor asynchrony-when the finger taps are in antiphase or arbitrary phase relative to the auditory sequence (Experiments 2 and 3) or when the tap coinciding with the sequence phase shift is withheld (Experiments 4 and 5). The phase correction observed in the latter conditions was instantaneous, which suggests that phase resetting occurs when the motor activity is discontinuous. A prolonged phase shift suggestive of overcompensation was observed in some conditions, which poses a challenge to pure phase correction models. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neurocognition and functional outcome in early-onset schizophrenia and attention-deficit/hyperactivity disorder: A 13-year follow-up.

Objective: The relation between neurocognitive impairments and functional outcome has been documented in both early onset schizophrenia (EOS) and attention-deficit/hyperactivity disorder (ADHD), but less is known about the long-term relation between these factors. The present study investigates how neurocognition at baseline is related to measures of functional outcome at 13-year follow-up in subjects with EOS and ADHD. Method: Subjects with EOS (n = 15), ADHD (n = 19), and healthy controls (n = 30) were followed up 13 years after initial assessment. All subjects were between 12 and 18 years of age at baseline and between 24 and 30 at follow-up. They were retested at T2 with the same comprehensive neurocognitive test battery as used at T1, and reassessed with various symptom and behavior ratings and functional outcome measures. Results: Both groups were characterized by reduced functional outcome at follow-up, although of different magnitude and type, compared with healthy controls. In the EOS group, neurocognitive baseline measures were associated with social functioning at follow-up (η2 between .26 and .41), while for the ADHD group, no significant predictions were found. Conclusions: Adolescents with EOS and ADHD are characterized by poor functional outcome compared with healthy controls when reassessed as young adults. Executive function, memory and attention were related to social and community functioning in EOS. For ADHD no significant predictions were found although functional outcome was poor. For both groups treatment should focus on training of social skills and activities of daily living to enhance the long-term functional outcome. For EOS cognitive remediation should also be considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Improved temporal stability in multieffector movements.

Four experiments compared the temporal stability of actions involving either 1 or more effectors. A reduction in within-effector temporal variability was observed during 2-effector tapping relative to when either effector moved alone. This phenomenon was observed for various limb combinations, and it did not require that the timed movements be produced in a repetitive manner. Moreover, an additional reduction in variability was found when tapping involved 3 effectors. This multiple effector advantage was multiplicative: The magnitude of the advantage was greater for longer target intervals. It is proposed that independent temporal representations are generated for each effector. These representations are integrated to produce coordinated motor cornmands, and the multiple effector advantage is a statistical consequence of the integration process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Compatibility of motion facilitates visuomotor synchronization.

Prior research indicates that synchronized tapping performance is very poor with flashing visual stimuli compared with auditory stimuli. Three finger-tapping experiments compared flashing visual metronomes with visual metronomes containing a spatial component, either compatible, incompatible, or orthogonal to the tapping action. In Experiment 1, synchronization success rates increased dramatically for spatiotemporal sequences of both geometric and biological forms over flashing sequences. In Experiment 2, synchronization performance was best when target sequences and movements were directionally compatible (i.e., simultaneously down), followed by orthogonal stimuli, and was poorest for incompatible moving stimuli and flashing stimuli. In Experiment 3, synchronization performance was best with auditory sequences, followed by compatible moving stimuli, and was worst for flashing and fading stimuli. Results indicate that visuomotor synchronization improves dramatically with compatible spatial information. However, an auditory advantage in sensorimotor synchronization persists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rubbing your stomach while tapping your fingers: Interference between motor planning and semantic judgments.

Previous research (R. L. Klatzky et al, 1989) shows that the time required to make sensible/nonsensible judgments about an action-object phrase (e.g., "rub your stomach") is reliably faster when the phrase is preceded by a cue representing a specific prototypical hand shape (vs a neutral cue). The current experiments investigated the effects of preparing for an alternate task (finger tapping vs syllable vocalization) on facilitatory priming of sensibility judgments. Preparation for finger tapping reduced the magnitude of the priming effect more than preparation for vocalization, suggesting that the resources accessed during semantic processing of action-object phrases are also used during manual response preparation. Results support the existence of a system representing manual actions that is limited in the number of activities that can be represented at one time and that is not so general that it represents manual and vocal tract movements. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Manual preference for tapping in infants.

Used 2 tapping tasks to determine whether individual infants' right- or left-hand (RH and LH, respectively) preference for unimanual and bimanual tapping corresponded to their handedness in bimanual manipulation tasks (bimanual handedness) during the 2nd yr of life, and whether the developmental onset of a manual tapping preference occurred before or after the onset of bimanual handedness at the end of the 1st yr of life. At each of 2 age levels (15 and 22 mo, 24 Ss each), most infants demonstrated an RH preference in both tapping tasks, whether they showed bimanual right- or left-handedness. Nevertheless, a sizable minority of bimanual LH, but not RH, demonstrated an LH preference across tapping tasks. Since research with adults suggests left-hemisphere specialization for speech in almost all RH and many LH individuals, it is possible that a manual preference for tapping in infants, with appropriate empirical validation, will prove a reliable index of this specialization. In addition, 16 10-mo-olds demonstrated a manual preference in the unimanual tapping task whether they showed bimanual handedness, but few demonstrated a preference in the bimanual tapping task. This latter finding is consistent with past research using other handedness tasks with infants, which suggests that unimanual handedness precedes bimanual handedness. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Congruency effects between number magnitude and response force.

Numbers are thought to be represented in space along a mental left–right oriented number line. Number magnitude has also been associated with the size of grip aperture, which might suggest a connection between number magnitude and intensity. The present experiment aimed to confirm this possibility more directly by using force as a response parameter. Participants judged parity of a single digit by executing a weak or forceful key press. Response selection was faster when small digits required a weak response and large digits required a forceful response than when this mapping was reversed. These findings indicate an effect of number magnitude on the initiation of response intensity. There was no evidence for such an effect on response execution because the actually applied response force was not associated with number magnitude. These findings confirm a previously postulated link between different magnitude domains such as number magnitude and intensity as a basis for action. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

When two hands are better than one: Reduced timing variability during bimanual movements.

Within-hand variability was reduced on a repetitive tapping task when individuals tapped with 2 hands in comparison to single-handed tapping. When the total variability was decomposed into central timing and peripheral implementation components (A.M. Wing and A.B. Kristofferson; see record 1974-10323-001), the bimanual advantage was attributed to decreased central variability. The improved consistency does not require that the movements involve homologous muscles. However, unlike phase coupling, the bimanual advantage is not found when the 2 movements are produced by different individuals, but rather requires that the 2 movements be produced by 1 individual. It is proposed that separate timing mechanisms are associated with each effector. During bimanual movements, the outputs from these timing mechanisms are integrated prior to movement execution, and it is this integration that results in the bimanual advantage. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Removal of polymerase-produced mutant sequences from PCR products

Heteroduplex DNA lacking d(GATC) methylation is subject to mismatch-provoked double-strand cleavage at d(GATC) sites in a reaction dependent on MutH, MutL, MutS, and ATP. We have exploited this reaction to develop a method for removal of polymerase-produced mutant sequences that arise during sequence amplification by PCR. After denaturation and reannealing, the PCR product pool is subjected to MutH, MutL, and MutS mismatch repair proteins under double-strand cleavage conditions, followed by isolation of uncleaved product by size selection. Use of an Escherichia coli lac forward mutation assay has shown that this procedure reduces the incidence of polymerase-induced mutant sequences by an order of magnitude. Twenty mutants that originated from three independent PCR amplification reactions and survived MutHLS treatment all were found to contain an infrequently occurring A.T --> T.A transversion mutation at a unique position within the product. By contrast, the majority of mutations in untreated PCR products were transitions occurring throughout the amplified region, although frameshifts and transversions also were observed. The MutHLS method thus can be used to effectively remove the majority of mutant sequences produced by polymerase errors during PCR amplification.     

Lengthing the duration of response execution does not modulate blindness to action-compatible stimuli.

Action-compatible blindness refers to the finding that target stimuli are perceived less frequently if they are presented during the planning or execution of a compatible action (e.g., a left arrow presented during a left manual key press) than during an incompatible action (J. Müsseler and B. Hommel, 1997 a, b). We investigated the effect of lengthening the response execution phase in the action-compatible blindness paradigm by requiring subjects to tap a response key once or three times on the assumption that tapping three times would increase the duration of the execution phase of the response. Prior research (e.g., B. Stevanovski et al (2002); P. Wühr and J. Müsseler, [2001]) has shown that larger blindness effects are observed for targets presented during the execution phase of a response than after the response has been made. We investigated whether a larger blindness effect would be observed in the three-tap condition than in the one-tap condition, or whether lengthening the duration of the response would extend the time course of the blindness effect. Neither of these possibilities was supported by the data irrespective of whether the number of taps to be made was blocked or mixed within a block of trials. The results are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Response bias and Murdock's D scale.

Murdock's D scale predicts a U shaped curve of % correct identification as a function of the position of the stimulus. An inadequacy in the D scale was brought to light in an absolute judgment study by this author. Ss displayed a powerful response bias, avoiding end responses, when judging line lengths. A simple correction for such a response frequency imbalance is suggested, and with this correction the line-length data support the D scale approach to the quantification of distinctiveness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Coping through emotional approach: Problems of conceptualizaton and confounding.

Two studies supported hypotheses that (1) published scales tapping coping through processing and expressing emotion are confounded with psychopathology; (2) previously demonstrated relations between emotional approach coping (EAC) and maladjustment are partially spurious; and (3) EAC, when tapped by items uncontaminated by distress, is beneficial under specific conditions. In Study 1, 194 psychologists rated a majority of published items, but no author-constructed EAC item, as indicative of pathology. Study 2 assessed relations of confounded and unconfounded EAC scales to 171 young adults' adjustment during stressful events. Confounded items evidenced weaker discriminant validity with distress measures than did unconfounded items, and they were weaker predictors of later maladjustment when initial adjustment was controlled than when it was not. Unconfounded EAC predicted improved adjustment for women and poorer adjustment for men over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Premenstrual and menstrual mood changes in adolescent women.

Studied the presence and magnitude of menstrual-cycle-related mood changes using standardized measures of depression and anxiety. 158 females aged 15–16 yrs completed the Menstrual Distress Questionnaire and reported the actual date of onset of their next 2 menstrual periods. These Ss and their male classmates were later given the Depression Adjective Check List, Forms A and D, and the State-Trait Anxiety Inventory twice, 2 wks apart, in an unrelated classroom setting. This study assessed the magnitude of anxiety and depression experienced by the 29 Ss who were tested within 4 days preceding the onset of menstruation and the 23 Ss who were tested during the first 4 days of menstruation. Premenstrual and menstrual test scores were compared with those obtained during the intermenstrual phase of the cycle. No significant differences in mood attributable to cycle phase were found. A control group of males also showed no significant difference in mood. Adolescent women appear to be different from women over 30 who have been reported to show significantly increased state anxiety and depression during the premenstrual phase of the menstrual cycle. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

SNARC-like congruency based on number magnitude and response duration.

Recent findings demonstrated that number magnitude affects the perception of display time (B. Xuan, D. Zhang, S. He, & X. Chen, 2007). Participants made fewer errors when display time (e.g., short) and magnitude (e.g., small) matched, suggesting an influence of magnitude on time perception. With the present experiment, the authors aimed to extend these findings by investigating whether number magnitude and time are also connected at the response level. Participants judged the parity of single digits by pressing a response key for either a short or a long duration. Responses were faster when small numbers required short keypresses and large numbers required long keypresses. In addition, overall keypress durations were affected by number magnitude. The results suggest a connection between number magnitude and time at the levels of response initiation and execution, thus supporting theories outlining a common magnitude system comprising time, space, and magnitude. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dividing attention between the hands and the head: Performance trade-offs between rapid finger tapping and verbal memory.

Tested a multiple resources approach to time-sharing performance which assumes that each cerebral hemisphere controls its own set of processing resources that it cannot share with the other hemisphere. Right-handed men performed a verbal memory task while concurrently tapping the index finger of either hand as rapidly as possible. Task priority was manipulated with a payoff scheme. Ss remembered more on the verbal task when concurrently tapping with their left hands than when tapping with their right hands, and their memory performance was much better when the memory task was emphasized than when the tapping task was emphasized, regardless of hand. For the tapping task, decrements from baseline tapping rates and trade-offs between tasks were equal for both hands when Ss were reading the to-be-remembered words aloud. In contrast, during the retention interval, decrements were larger for the right hand than the left, and there were no task trade-offs. On right-hand trials, both tasks required exclusively left-hemisphere resources, whereas on left-hand trials, right-hemisphere resources were required to execute the tapping movements per se, but left-hemisphere resources were necessary to coordinate those movements with the movements required for overt speech. The data underscore the importance of manipulating task priority to obtain an accurate picture of a task's resource requirements. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Timing processes are correlated when tasks share a salient event.

Event timing is manifested when participants make discrete movements such as repeatedly tapping a key. Emergent timing is manifested when participants make continuous movements such as repeatedly drawing a circle. Here we pursued the possibility that providing salient perceptual events to mark the completion of time intervals could allow circle drawing and tapping to share a common timing process. Individual differences in timing performance were correlated in the tapping and circle drawing tasks when a salient auditory event marked the completion of a cycle. The results suggest that the distinction between event timing and emergent timing does not inhere solely in kinematics but inheres as well in the way task goals are represented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An electron diffraction analysis of turbostratic graphite in cemented carbides

Electron diffraction patterns of nesting sequences of two-dimensionally crystallised polar-cap shaped turbostratic graphite often have fine spotty reflections lying in short streaks, whereas infinitely long reciprocal lattice rods (relrods) are expected for layered structures where every basal plane in the crystal is randomly rotated about the c-axis. In graphite the first order hk reflections of the relrods are 10 reflections. The short streaks are intense when polar caps have flattened poles because many streaks are then superimposed. Dark field microscopy shows that the short streaks image the flattened polar regions only and therefore these regions reflect only into the streaks. Models of the reciprocal lattice of layered structures combined with a model of partially crystallised graphite which has transformed from f.c.c. β-SiC, suggest that there is a relationship between the angles of rotation of basal planes, fixed by the stacking of {111} planes of a parent f.c.c. phase, and the thickness of platelets of perfect graphite forming in the process. Rotation of such platelets about the c-axis would still produce a turbostratic structure but because basal planes are now not all randomly rotated the lengths of the reciprocal lattice rods, which are inversely proportional to the thickness of platelets, would be correspondingly shorter. The shortness of the observed streaks is therefore an indication of the degree of crystallinity of the graphite.     

Directly assessing the relationship between irrelevant speech and irrelevant tapping.

The acoustic confusion effect is the finding that lists of to-be-remembered items that sound similar to one another are recalled worse than otherwise comparable lists of items that sound different. Previous work has shown that concurrent irrelevant speech and concurrent irrelevant tapping both reduce the size of this effect, suggesting similarities between the two manipulations. The authors assessed the relation between irrelevant speech and irrelevant tapping by correlating the disruption each causes to recall of similar- and dissimilar-sounding items. A significant correlation was obtained, indicating a relation between the two. The results indicate that researchers should be sensitive to changes in the magnitude of the effects rather than focusing exclusively on the presence or absence of particular effects. Implications for the 3 major explanations of the irrelevant speech effect are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)