Terminal Feedback Outperforms Concurrent Visual,Auditory, and Haptic Feedback in Learning a Complex Rowing-Type Task

Augmented feedback, provided by coaches or displays, is a well-established strategy to accelerate motor learning. Frequent terminal feedback and concurrent feedback have been shown to be detrimental for simple motor task learning but supportive for complex motor task learning. However, conclusions on optimal feedback strategies have been mainly drawn from studies on artificial laboratory tasks with visual feedback only. Therefore, the authors compared the effectiveness of learning a complex, 3-dimensional rowing-type task with either concurrent visual, auditory, or haptic feedback to self-controlled terminal visual feedback. Results revealed that terminal visual feedback was most effective because it emphasized the internalization of task-relevant aspects. In contrast, concurrent feedback fostered the correction of task-irrelevant errors, which hindered learning. The concurrent visual and haptic feedback group performed much better during training with the feedback than in nonfeedback trials. Auditory feedback based on sonification of the movement error was not practical for training the 3-dimensional movement for most participants. Concurrent multimodal feedback in combination with terminal feedback may be most effective, especially if the feedback strategy is adapted to individual preferences and skill level.     

Acquisition of Effector-Specific and Effector-Independent Components of Sequencing Skill

In a serial reaction time task, participants practiced a repeating sequence with 1 hand. In interleaved blocks, they responded to random sequences with the other hand. Experiment 1 was composed of 5 sessions, each consisting of 30 blocks. Intermanual transfer, reflecting a hand-independent component of sequence knowledge, increased across session. A smaller but significant, nontransferable, and hand-specific component was evident in each session and did not increase with practice. Experiment 2 comprised only 1 session. Uninterrupted practice (no interleaved random blocks) improved hand-independent sequence learning in comparison with interrupted practice (as implemented in Experiment 1), whereas hand-specific sequence learning was unaffected by this between-subjects manipulation. These findings suggest separate mechanisms for effector-independent sequence learning and effector-specific acquisition of optimized response coarticulation.     

Increased Jump Height with an External Focus Due to Enhanced Lower Extremity Joint Kinetics

Sensorimotor abilities are crucial for performance in athletic, military, and other occupational activities, and there is great interest in understanding learning in these skills. Here, behavioral performance was measured over three days as twenty-seven participants practiced multiple sessions on the Nike SPARQ Sensory Station (Nike, Inc., Beaverton, Oregon), a computerized visual and motor assessment battery. Wrist-worn actigraphy was recorded to monitor sleep–wake cycles. Significant learning was observed in tasks with high visuomotor control demands but not in tasks of visual sensitivity. Learning was primarily linear, with up to 60% improvement, but did not relate to sleep quality in this normal-sleeping population. These results demonstrate differences in the rate and capacity for learning across perceptual and motor domains, indicating potential targets for sensorimotor training interventions.     

Persian speaking children's acquisition of relative clauses

The current study examined the acquisition of relative clauses (RCs) in Persian-speaking children. Persian is a relatively unique data point in crosslinguistic research in acquisition because it is a head-final language with post-nominal RCs. Children (N = 51) aged 2 to 7 years completed a picture-selection task that tested their comprehension of subject-, object-, and genitive-RCs. The results showed that the children experienced greater difficulty processing object and genitive RCs when compared to subject RCs, suggesting that the children have particular difficulty processing sentences with non-canonical word order. The results are discussed with reference to a number of theoretical accounts proposed to account for sentence difficulty.     

Primitive computations in speech processing

Previous research suggests that artificial-language learners exposed to quasi-continuous speech can learn that the first and the last syllables of words have to belong to distinct classes (e.g., Endress & Bonatti, 2007; Peña, Bonatti, Nespor, & Mehler, 2002). The mechanisms of these generalizations, however, are debated. Here we show that participants learn such generalizations only when the crucial syllables are in edge positions (i.e., the first and the last), but not when they are in medial positions (i.e., the second and the fourth in pentasyllabic items). In contrast to the generalizations, participants readily perform statistical analyses also in word middles. In analogy to sequential memory, we suggest that participants extract the generalizations using a simple but specific mechanism that encodes the positions of syllables that occur in edges. Simultaneously, they use another mechanism to track the syllable distribution in the speech streams. In contrast to previous accounts, this model explains why the generalizations are faster than the statistical computations, require additional cues, and break down under different conditions, and why they can be performed at all. We also show that that similar edge-based mechanisms may explain many results in artificial-grammar learning and also various linguistic observations.     

The role of working memory in information acquisition and decision making: Lessons from the binary prediction task

The effects of memory constraints upon information acquisition and decision making were examined in two experiments using binary prediction tasks, where participants observe outcomes for two options before deciding which one to bet upon. Our studies extend previous investigations to the case where participants learn the structure of the task through observation, but where information acquisition is separated from the task of prediction. Participants with higher cognitive capacity (larger memory span or higher intelligence) were more likely to adopt the “maximizing” strategy (always selecting the more frequent alternative). This finding conflicts with some recent investigations of similar tasks, a contrast that implies that the presence of feedback on choices may be important in determining the strategic actions of high-capacity individuals. Participants selecting the optimal strategy were in turn more efficient in their data acquisition. The behaviour of participants adopting suboptimal choice strategies was consistent with prediction based upon a “narrow window of experience”—that is, seeking to match the characteristics of small samples of observations.     

Age-of-acquisition effects in pure alexia

Pure alexia is an acquired reading disorder in which previously literate adults adopt a letter-by-letter processing strategy. Though these individuals display impaired reading, research shows that they are still able to use certain lexical information in order to facilitate visual word processing. The current experiment investigates the role that a word's age of acquisition (AoA) plays in the reading processes of an individual with pure alexia (G.J.) when other lexical variables have been controlled. Results from a sentence reading task in which eye movement patterns were recorded indicated that G.J. shows a strong effect of AoA, where late-acquired words are more difficult to process than early-acquired words. Furthermore, it was observed that the AoA effect is much greater for G.J. than for age-matched control participants. This indicates that patients with pure alexia rely heavily on intact top-down information, supporting the interactive activation model of reading.     

Age of acquisition affects the retrieval of grammatical category information

This study investigated age of acquisition (AoA) effects on processing grammatical category information of Chinese single-character words. In Experiment 1, nouns and verbs that were acquired at different ages were used as materials in a grammatical category decision task. Results showed that the grammatical category information of earlier acquired nouns and verbs was easier to retrieve. In Experiment 2, AoA and predictability from orthography to grammatical category were manipulated in a grammatical category decision task. Results showed larger AoA effects under lower predictability conditions. In Experiment 3, a semantic category decision task was used with the same materials as those in Experiment 2. Different results were found from Experiment 2, suggesting that the grammatical category decision task is not merely the same as the semantic category decision task, but rather involves additional processing of grammatical category information. Therefore the conclusions of Experiments 1 and 2 were strengthened. In summary, it was found for the first time that AoA affects the retrieval of grammatical category information, thus providing new evidence in support of the arbitrary mapping hypothesis.     

Age-of-acquisition effects in novel picture naming: A laboratory analogue

Age-of-acquisition (AoA) effects are such that early-acquired items are more quickly recognized and produced than later acquired items. In this laboratory analogue, participants were trained to name a group of Greeble pictures with a novel nonsense name. We manipulated order of acquisition of the stimuli: Half of the stimuli were presented from the onset of training (early acquired) whilst the other half were introduced later in the training schedule (late acquired). At test, when early and late stimuli had equal cumulative frequency, early stimuli were named significantly faster than late items. In a second test, it was also found that visual duration thresholds were significantly smaller for the early items when participants were asked to name the critical items. These findings support the notion that order-of-acquisition effects can be manifest over a short time span in the laboratory, and that the effect of order of acquisition is distinct from mere frequency of exposure. The findings are consistent with the idea that AoA effects occurring over a large temporal scale may be a special case of more general order-of-acquisition effects, and both may be a general property of learning mechanisms.