Effects of imposed delay of response and item complexity on auditory comprehension by aphasics

Ten aphasic and five control subjects were administered an auditory comprehension task similar to Levels I-IV of the Revised Token Test under conditions of 0, 5, 10, and 20 sec of imposed response delay. Responses were evaluated in terms of performance accuracy and response time. Aphasic subjects' response accuracy was significantly effected by an interaction between the length of delay imposed and the complexity of the stimulus. The aphasic group also demonstrated a significant main effect for item complexity. Control subjects' accuracy was not influenced by the treatment conditions. Latency measures indicated the aphasic subjects were slower to respond across all treatment conditions. Both groups' latency scores were significantly effected by item complexity. A comparison of mean latencies by condition did, however, suggest different patterns of response for the two groups. Results are discussed in terms of theoretical and clinical implications for the auditory comprehension deficits of aphasia.     

Alternatives to switch-cost scoring in the task-switching paradigm: Their reliability and increased validity

In the task-switching paradigm, the latency switch-cost score—the difference in mean reaction time between switch and nonswitch trials—is the traditional measure of task-switching ability. However, this score does not reflect accuracy, where switch costs may also emerge. In two experiments that varied in response deadlines (unlimited vs. limited time), we evaluated the measurement properties of two traditional switch-cost scoring methods (the latency switch-cost score and the accuracy switch-cost score) and three alternatives (a rate residual score, a bin score, and an inverse efficiency score). Scores from the rate residual, bin score, and inverse efficiency methods had comparable reliability for latency switch-cost scores without response deadlines but were more reliable than latency switch-cost scores when higher error rates were induced with a response deadline. All three alternative scoring methods appropriately accounted for differences in accuracy switch costs when higher error rates were induced, whereas pure latency switch-cost scores did not. Critically, only the rate residual and bin score methods were more valid indicators of task-switching ability; they demonstrated stronger relationships with performance on an independent measure of executive functioning (the antisaccade analogue task), and they allowed the detection of larger effect sizes when examining within-task congruency effects. All of the three alternative scoring methods provide researchers with a better measure of task-switching ability than do traditional scoring methods, because they each simultaneously account for latency and accuracy costs. Overall, the three alternative scoring methods were all superior to the traditional latency switch-cost scoring method, but the strongest methods were the rate residual and bin score methods.     

Response latency as a predictor of the accuracy of children's reports

Researchers have explored various diagnostic cues to the accuracy of information provided by child eyewitnesses. Previous studies indicated that children's confidence in their reports predicts the relative accuracy of these reports, and that the confidence-accuracy relationship generally improves as children grow older. In this study, we examined the added contribution of response latency to the prediction of children's accuracy over and above that of confidence ratings. In Experiments 1 and 2, 2nd and 5th graders studied picture-event pairs and were tested using forced-choice, 2-alternative, or 5-alternative questions. In Experiment 3, children watched a slideshow depicting a story and were tested by 5-alternative questions about story details. The children indicated their confidence in each response, and response latency was measured. The results of all experiments suggested that children in both age groups relied on response latency as a cue for confidence, and this reliance contributed to the success with which they monitored the accuracy of their reports. When the test format was easy (Experiment 1), 2nd graders were as accurate as 5th graders in monitoring the accuracy of their answers, and the latency of their responses was no less predictive of accuracy. When the task was more difficult, age differences emerged. Nevertheless, in all experiments and for both age groups, response latency was found to have added value for predicting accuracy over and above that of confidence. Theoretical and practical implications of these findings for predicting the accuracy of children's reports are discussed.     

Speed-accuracy tradeoff in double stimulation: Effects on the first response

A single-stimulation and two double-stimulation response conditions were compared using explicit payoff matrices to vary speed-accuracy tradeoff. Under accuracy payoff, response latency (RT(1)) to the first stimulus increased as ISI dropped but accuracy remained high and relatively constant. Under speed payoff, RT(1) was only slightly affected by ISI but accuracy dropped as ISI decreased. Transmitted information rates consistently reflected detrimental effects of short ISI. In double stimulation, but not in single stimulation, error response latency exceeded correct response latency. Furthermore, error response latencies were found to be far more variable and more sensitive to changes in speed-accuracy condition than were correct response latencies. Finally, under both speed and accuracy conditions, response latency to the first of two successive stimuli was faster if a response was also required to the second stimulus. Implications of the data for possible models of double-stimulation speed-accuracy tradeoff are considered.     

Averaged occipital responses to stimulation of sites in the upper and lower halves of the retina

Averaged responses of the occipital lobes to flashes imposed along the midline of the upper part of the retina are larger and of shorter latency than responses to flashes imposed on the lower retina. Since reaction times also are shorter when the upper retina is stimulated, this study provides further evidence for the generalization that reaction time varies inversely with amplitude and directly with latency of the evoked response.     

Dissociation between Categorical and Coordinate Spatial Computations: Modulation by Cerebral Hemispheres, Task Properties, Mode of Response, and Age

Kosslyn suggested a dissociation of two kinds of spatial representations: categorical and coordinate, the former computed by the left hemisphere and the latter by the right hemisphere. In addition, with practice, a “categorization” of the coordinate computation would appear. These suggestions resulted largely from an experiment, replicated by others, in which the subjects had to estimate the relative position of a dot and a line by giving an oral response, and feedback was provided. The present series of five experiments was an attempt to test whether this finding could be generalized, under several methodological manipulations, some of which have already been used by researchers in separate studies. In the five experiments, accuracy was a more contributive dependent variable than correct latencies, and practice effects on the task × field interaction were not verified. Experiments 1–3 concerned the kind of response. When a manual instead of an oral response was required (Experiment 1;n= 32 Ss), the expected dissociation was observed (as well as when the latency of responses made by the right hand were studied). When the number of oral responses was increased from two (a binary choice) to eight, the dissociation was still observed for accuracy but disappeared when a more liberal criterion of accuracy was used to reduce the considerable task effect (Experiment 2;n= 32 Ss), or when response requirements were equated for both tasks (Experiment 3;n= 32 Ss). In Experiment 4 (n= 32 Ss), a manual response was called but the feedback was removed and the task dissociation disappeared. Finally, the task dissociation observed in Experiment 1 was not verified when a sample of elderly subjects was enrolled (Experiment 5;n= 32 Ss). However, age per se was the source of an interesting additional dissociation since only the coordinate computation was age sensitive. Our results suggest that the dissociation proposed by Kosslyn between the computation of categorical vs coordinate spatial relationships is highly unstable and sensitive to subtle methodological factors (vocal vs manual response, presence vs absence of feedback, binary vs “continous” response, age) which could preclude its general application.     

Aging, encoding fluency, and metacognitive monitoring

Encoding fluency (how rapidly one generates a mediator for a new association) may be a cue used to judge one's own learning. To evaluate age differences in utilization of this cue, older and younger adults were instructed to use interactive imagery to study paired associates, pressing a button to indicate when an image had been formed for a given pair. A judgment of learning (JOL) was also made immediately after each pair had been studied. Hence, at least two cues pertaining to encoding fluency-whether an image had been formed (a diagnostic cue) and the latency of formation (a nondiagnostic one)-were available when making JOLs. Age equivalence was found in JOL accuracy, and JOLs for both age groups were positively related to imagery formation and were negatively related to the latency of image formation. Moreover, subjectively judged latency correlated higher with JOLs than actual (objective) latency, supporting the hypothesis that perceived fluency is a cue used in constructing JOLs.     

Response elimination in rats with schedules of omission training, including yoked and response-independent reinforcement comparisons

After rats were trained to lever press, response elimination began with factorial combinations of fixed vs variable and adjusting vs constant omission training schedules. A time interval scheduling reinforcement remained the same in a constant schedule, and its length was increased as response rate declined in the adjusting schedule. A variable time (VT) response-independent reinforcement schedule followed response elimination to test the durability of response cessation. Experiment I included groups whose reinforcement was yoked to that received by the omission schedule groups. Rate of response elimination was faster with an adjusting than a constant schedule, and slightly faster with a variable than a fixed schedule. There were no significant differences in rate of response elimination between omission schedule and yoked groups. Shorter delay of reinforcement tended to increase rate of response elimination. In the subsequent VT durability test all groups displayed near-zero response rates. In Experiment II adjusting fixed and variable omission schedules, including yoked groups, were compared with fixed time (FT) and VT reinforcement schedules. Response elimination was slower in the FT and VT groups, and they responded more in a subsequent VT durability test. It was concluded that differential reinforcement of other behavior fails to account for these omission training effects, and suggestions were made for an analysis based on the correlation between response and reinforcement rate.     

Intelligence and information processing during an auditory discrimination task with backward masking: an event-related potential analysis

The relation between mental ability and auditory discrimination ability was examined by recording event-related potentials from 60 women during an auditory oddball task with backward masking. Across conditions that varied in intensity and in the interval between the target and masking stimuli, the higher ability (HA) group exhibited greater response accuracy, shorter response times, larger P3 amplitude, and shorter P3 latency to target stimuli than the lower ability (LA) group. When instructed to ignore the stimuli, the HA group exhibited shorter mismatch negativity latency to deviant tones than the LA group. The greater speed and accuracy of auditory discrimination for the HA group, observed here with multiple measures, is not a consequence of response strategy, test-taking ability, or attention deployment.     

Variation in working memory capacity,fluid intelligence,and episodic recall: A latent variable examination of differences in the dynamics of free recall

A latent variable analysis was conducted to examine the nature of individual differences in the dynamics of free recall and cognitive abilities. Participants performed multiple measures of free recall, working memory capacity (WMC), and fluid intelligence (gF). For each free recall task, recall accuracy, recall latency, and number of intrusion errors were determined, and latent factors were derived for each. It was found that recall accuracy was negatively related to both recall latency and number of intrusions, and recall latency and number of intrusions were positively related. Furthermore, latent WMC and gF factors were positively related to recall accuracy, but negatively related to recall latency and number of intrusions. Finally, a cluster analysis revealed that subgroups of participants with deficits in focusing the search had deficits in recovering degraded representations or deficits in monitoring the products of retrieval. The results are consistent with the idea that variation in the dynamics of free recall, WMC, and gF are primarily due to differences in search set size, but differences in recovery and monitoring are also important.     

Aging,Encoding Fluency,and Metacognitive Monitoring

ABSTRACT

Encoding fluency (how rapidly one generates a mediator for a new association) may be a cue used to judge one's own learning. To evaluate age differences in utilization of this cue, older and younger adults were instructed to use interactive imagery to study paired associates, pressing a button to indicate when an image had been formed for a given pair. A judgment of learning (JOL) was also made immediately after each pair had been studied. Hence, at least two cues pertaining to encoding fluency—whether an image had been formed (a diagnostic cue) and the latency of formation (a nondiagnostic one)—were available when making JOLs. Age equivalence was found in JOL accuracy, and JOLs for both age groups were positively related to imagery formation and were negatively related to the latency of image formation. Moreover, subjectively judged latency correlated higher with JOLs than actual (objective) latency, supporting the hypothesis that perceived fluency is a cue used in constructing JOLs.     

Determinants of associative response latency

The relationship between single-word, free-association response latency and the following characteristics of Kent-Rosanoff words were examined: ( a ) grammatical form class, ( b ) emotionality, ( c ) familiarity, and ( d ) D (the number of different response words given to a stimulus word in a single-word free-association situation by a group of subjects). In addition was examined the relationship between response latency and ( e ) the type of associative linkage constituted by the stimulus-response combination, and ( f ) response frequency. Given the limits posed by the present stimulus material, subject material, and analyses performed, the conclusion was reached that single-word, free-associative response latency is related primarily to D ( r =0.81), secondly to the frequency with which a given stimulus-response combination occurs in a group of subjects.     

视觉预期和注意指向对姿势和动作肌肉预期和补偿姿势调节的影响

采用经典落球试验研究范式,同步观察视觉预期和注意指向对腰部姿势肌肉和上肢运动肌肉预期和补偿姿势调节的影响,探索视觉预期和注意指向影响姿势控制的早期心理生理机制。24名青年志愿者(10名男性,14名女性)参与完成本实验,分别在有、无视觉预期以及注意指向"托盘稳定"或者"重心稳定"的实验条件下观察外部姿势干扰对腰部姿势肌肉(L5~S1腰部多裂肌)和上肢动作肌肉(肱二头肌)预期姿势调节(anticipatory postural adjustments,APAs)和补偿姿势调节(compensatory postural adjustments,CPAs)相关时间和强度参数的影响。APAs和CPAs的时间和强度参数通过获取被检肌肉s EMG信号并参照相关检测规范进行。结果显示:(1)视觉预期对多裂肌的APAs启动时间,对肱二头肌的APAs启动时间、APAs强度和CPAs强度有显著影响;(2)注意指向对多裂肌的CPAs启动时间和肱二头肌APAs启动时间有显著影响;(3)视觉预期和注意指向对肱二头肌的APAs启动时间和APAs强度有交互作用。研究认为,突发外部姿势干扰条件下姿势肌肉和动作肌肉的姿势调节策略具有一定的差异,视觉预期和注意指向仅对姿势肌肉的时间参数有影响,对动作肌肉APAs和CPAs时间和强度参数都产生调节作用,表明在中枢神经系统的姿势控制中,人体姿势策略的调节是通过对姿势肌肉和动作肌肉的双重控制来完成的,视觉预期效应和心理指向效应反映在对不同功能肌肉前馈控制和反馈控制相应参数的调节。     

Response latency and accuracy in visual word recogniton

In a single visual word recognition experiment, the effects of (1) eccentricity of presentation, (2) word length, and (3) word frequency were investigated. The stimuli used were Dutch nouns in two frequency classes of about 15 and 150.10^-6; word length varied from 1 to 10; eccentricity varied from ?4 to +4 deg. The response quality and response latency of 11 subjects were measured. For the correct responses, recognition scores decreased and response latencies increased with eccentricity; both showed asymmetrical curves in the visual field. It is argued that word length proper affects neither the probability of correct responses nor latency. A clear word frequency effect was established. The eccentricity of presentation is considered as the determinant of the amount of available information, thus directly influencing accuracy and latency. The linear relationship between accuracy and latency is a major finding. A word recognition scheme is offered which incorporates (1) activation, (2) decision, and (3) speech. The time relations between incoming retinal information and response decision, leading to an extra 400 msec for incorrect as compared with correct responses, are discussed. Word recognition in reading is examined, together with the impact of the present experimental results on information flow in successive eye fixations, eye movement control, and eye-voice span.     

Response latency and response accuracy as measures of memory

The relationship is examined between response accuracy and response latency as measures of memory, and questions are raised concerning the value of the unidimensionality assumption often invoked in theories of memory. Three paired-associate experiments investigated the effects of the length of the retention interval, the kind of processing during incidental learning, and the number of study versus test trials during intentional learning. The findings, together with a review of selected studies in the literature, support three conclusions: (1) Latency of correct recall is not necessarily more sensitive than accuracy, (2) accuracy and latency of correct recall measure different aspects of memory, and (3) latency of correct recall and latency of incorrect recall measure different aspects of memory. The available data disconfirm the idea that any unidimensional construct (such as strength or the amount of information in memory) underlies memory performance. An explanation is offered that emphasizes the distinction between encoding and retrieval processes.     

The persistence of the fluency–confidence association in problem solving

Confidence in answers is known to be sensitive to the fluency with which answers come to mind. One aspect of fluency is response latency. Latency is often a valid cue for accuracy, showing an inverse relationship with both accuracy rates and confidence. The present study examined the independent latency–confidence association in problem-solving tasks. The tasks were ecologically valid situations in which latency showed no validity, moderate validity, and high validity as a predictor of accuracy. In Experiment 1, misleading problems, which often elicit initial wrong solutions, were answered in open-ended and multiple-choice test formats. Under the open-ended test format, latency was absolutely not valid in predicting accuracy: Quickly and slowly provided solutions had a similar chance of being correct. Under the multiple-choice test format, latency predicted accuracy better. In Experiment 2, nonmisleading problems were used; here, latency was highly valid in predicting accuracy. A breakdown into correct and incorrect solutions allowed examination of the independent latency–confidence relationship when latency necessarily had no validity in predicting accuracy. In all conditions, regardless of latency’s validity in predicting accuracy, confidence was persistently sensitive to latency: The participants were more confident in solutions provided quickly than in those that involved lengthy thinking. The study suggests that the reliability of the latency–confidence association in problem solving depends on the strength of the inverse relationship between latency and accuracy in the particular task.     

Reinforcement and punishment in a closed system

Children chose between toys freely and with various restrictive contingencies. Sometimes play with a preferred toy was contingent on play with a nonpreferred toy. Sometimes play with a nonpreferred toy was contingent on play with a preferred toy. Another toy (free toy) was always available during contingency sessions. Because toy playing occupied the entire session the response system was closed. When one response increased in duration others had to decrease. An analysis of closed-system responding revealed that the restrictions of the closed system together with the restrictions imposed by the contingencies forced subjects to alter the proportion of time devoted to the three responses. A geometrical model representing the closed system and an analytical method based on distance are presented to describe the data.     

Haptic recognition of static and dynamic expressions of emotion in the live face

If humans can detect the wealth of tactile and haptic information potentially available in live facial expressions of emotion (FEEs), they should be capable of haptically recognizing the six universal expressions of emotion (anger, disgust, fear, happiness, sadness, and surprise) at levels well above chance. We tested this hypothesis in the experiments reported here. With minimal training, subjects' overall mean accuracy was 51% for static FEEs (Experiment 1) and 74% for dynamic FEEs (Experiment 2). All FEEs except static fear were successfully recognized above the chance level of 16.7%. Complementing these findings, overall confidence and information transmission were higher for dynamic than for corresponding static faces. Our performance measures (accuracy and confidence ratings, plus response latency in Experiment 2 only) confirmed that happiness, sadness, and surprise were all highly recognizable, and anger, disgust, and fear less so.     

Multi-stepping saccadic sequences in humans

A number of paradigms are reported in which multi-stepping saccadic sequences (MSS) are reliably elicited in normal subjects. It was observed that MSS are consistently associated with a prolongation of the initial saccade latency. Further experiments show that this phenomenon is validated across a number of independent eye movement tasks. However, the probability of MSS occurring is reduced when temporal constraints are imposed on the latency of the response. An interpretation of these task-elicited MSS in terms of the neural mechanisms controlling voluntary saccades is proposed.     

Conditioned reinforcement and discrimination performance

Pigeons were trained in a three-key chamber to peck one side key in the presence of a vertical line on the center key and to peck the other side key in the presence of a horizontal line. Correct choice responses were reinforced with food according to fixed- and variable-ratio, fixed-interval, and differential-reinforcement-of-long-latency schedules of reinforcement. For each schedule, the birds performed under each of two conditions: (1) each correct choice response produced a brief presentation of stimuli intermittently paired with food, then the next trial; (2) each correct choice response produced an intertrial interval only. For all schedules except one long latency schedule, response rates were higher under the condition of brief stimulus presentation than under the comparable control condition. Presentation of brief magazine stimuli increased choice accuracy. The amount of change in accuracy was correlated with the rate of food presentation. Performance under the schedules with highest food reinforcement rates showed no enhancement; performance under the schedules with the lowest reinforcement rates showed the greatest enhancement.