The influence of instructive feedback presentation schedule: A replication with children with autism spectrum disorder

Instructive feedback (IF) is a modification to discrete trial instruction that may increase instructional efficiency for individuals with autism spectrum disorder. Several variations of IF have recently been evaluated in the literature; however, few studies have assessed the effectiveness and efficiency of presenting secondary targets on continuous versus intermittent presentation schedules. The current study evaluated the effectiveness and efficiency of various presentation schedules of secondary targets during discrete trial instruction. Specifically, we replicated and extended Griffen et al. (1998) by comparing a condition in which secondary targets were presented during each trial of a session, a condition in which secondary targets were presented every other trial, and a condition in which secondary targets were presented about every 4 trials. Within-subject replications were included for both participants. One of the intermittent presentation schedules was associated with the most optimal outcomes in all 4 comparisons.     

Instructive feedback embedded within group instruction for children diagnosed with autism spectrum disorder

The present study evaluated the effects of instructive feedback embedded within a group discrete trial teaching to teach tact relations to nine children diagnosed with autism spectrum disorder using a nonconcurrent multiple‐baseline design. Dependent variables included correct responses for: primary targets (directly taught), secondary targets (taught via instructive feedback), primary observational targets (directly taught to other members of the group), and secondary observational targets (taught via instructive feedback provided to other members of the group). Results showed that all nine participants reached the mastery criterion for the primary targets, as well as acquired the secondary and observational targets without direct teaching. Clinical implications and areas for future research are provided.     

Cross-dimensional interference and cross-trial inhibition

In two experiments, we examined whether one source of cross-dimensional interference in visual search involves cross-trial position priming. In Experiment 1, we demonstrated cross-dimensional interference in search for an orientation-defined target: Search for a left-tilted target among right-tilted non-targets was disrupted by the presence of a singleton color distractor. In all conditions, search was facilitated when a target was presented at the same position as a target in the previous trial (positive position priming). In addition, there were negative effects of position priming on orientation targets that fell on the same side as singleton distractors on the previous trial. In Experiment 2, to examine the impact of negative position priming on cross-dimensional interference, trials with and without singleton distractors were presented in a single trial block. The chance of a singleton distractor's being present on a preceding trial was then equated across displays when the distractor was and when it was not subsequently present. Cross-dimensional interference was eliminated under this mixed presentation condition, suggesting that the cost of cross-dimensional interference was not determined by the stimulus-driven factors in the current trial, at least when a limited number of target and distractor locations was used. We conclude that top-down selection is possible during visual search, and this leads to inhibition of the location of salient distractors. The cost of this is slowed detection of targets at inhibited locations on subsequent trials.     

Visual search for dimensionally redundant pop-out targets: evidence for parallel-coactive processing of dimensions

In two visual search experiments, the detection of singleton feature targets redundantly defined on multiple dimensions was investigated. Targets differed from the distractors in orientation, color, or both (redundant targets). In Experiment 1, the various target types were presented either in separate blocks or in random order within blocks. Reaction times to redundant targets significantly violated the race model inequality (Miller, 1982), but only when there was constancy of the target-defining dimension(s) within trial blocks. In Experiment 2, there was dimensional variability within blocks. Consistent with Experiment 1, constancy of the target-defining dimension(s), but this time across successive trials (rather than within blocks), was critical for observing violations of the race model inequality. These results provide evidence for parallel-coactive processing of multiple dimensions, consistent with the dimension-weighting account of Müller, Heller, and Ziegler (1995).     

The role of timing deviations and target position uncertainty on temporal attending in a serial auditory pitch discrimination task

Listeners were presented with sequences of tones that ascended in semitone intervals. On each trial a single target tone in the sequence was displaced in pitch, and listeners were required to indicate whether the target tone was higher or lower than its normal pitch. Task constraints, specifically target serial position uncertainty and the probabilistic relationship between time deviations and target tones, were varied in order to determine the impact of task constraints on temporal attending strategy. When listeners had no advance knowledge of the serial position of the target, and early and late targets provided information regarding target serial position, performance was better for early and late target trials than for on-time target trials (Experiment 1). When listeners had no advance knowledge of the serial position of the target, and early and late temporal deviations provided no information regarding target serial position, performance for late target trials was superior to that for early and on-time target trials (Experiment 2). Finally, when target serial position uncertainty was eliminated, performance was equivalent across all three levels of target timing (early, on time, late). The results indicate that performance profiles based on stimulus timing properties are affected by various task constraints as well as by stimulus properties.     

Strategies of flanker coprocessing in single and dual tasks

In this study, the authors used a dual-task flanker paradigm to investigate the degree to which flankers are coprocessed with the target as a function of whether flankers have to be used as stimuli for a second task. A series of experiments, in which performance in dual tasks was compared with that in single tasks, revealed that participants had a strong tendency to coprocess flankers to a large degree in dual tasks, even if this impaired performance. Coprocessing of flankers was reduced only when totally irrelevant flankers were presented at the beginning of a trial or single tasks were performed on the great majority of trials within a block. The results suggest that it was demanding to process targets and flankers serially when both had to be used for a dual task. As a consequence, target and flankers were processed in parallel, even if this was nonoptimal for target selection.     

Evaluating discrete trial teaching with instructive feedback delivered in a dyad arrangement via telehealth

Telehealth research in the field of applied behavior analysis (ABA) has focused on the training and supervision of others to implement various behavior analytic procedures. Current guidelines for practicing telehealth suggest that direct telehealth services may be appropriate for some individuals diagnosed with autism spectrum disorder, but more research is needed. This study evaluated the effects of discrete trial teaching with instructive feedback in a dyad arrangement delivered directly via telehealth to teach tact relations to 6 children diagnosed with autism spectrum disorder. All participants and the experimenter were located in different physical locations. All participants learned their primary and secondary targets, and 5 of the participants acquired the observational primary and secondary targets without direct teaching. Areas of future research and clinical implications are discussed in the context of telehealth service delivery.     

Teaching children with autism spectrum disorder to tact olfactory stimuli

Research on tact acquisition by children with autism spectrum disorder (ASD) has often focused on teaching participants to tact visual stimuli. It is important to evaluate procedures for teaching tacts of nonvisual stimuli (e.g., olfactory, tactile). The purpose of the current study was to extend the literature on secondary target instruction and tact training by evaluating the effects of a discrete‐trial instruction procedure involving (a) echoic prompts, a constant prompt delay, and error correction for primary targets; (b) inclusion of secondary target stimuli in the consequent portion of learning trials; and (c) multiple exemplar training on the acquisition of item tacts of olfactory stimuli, emergence of category tacts of olfactory stimuli, generalization of category tacts, and emergence of category matching, with three children diagnosed with ASD. Results showed that all participants learned the item and category tacts following teaching, participants demonstrated generalization across category tacts, and category matching emerged for all participants.     

Visual search for dimensionally redundant pop-out targets: Evidence for parallel-coactive processing of dimensions

In two visual search experiments, the detection of singleton feature targets redundantly defined on multiple dimensions was investigated. Targets differed from the distractors in orientation, color, or both (redundant targets). In Experiment 1, the various target types were presented either in separate blocks or in random order within blocks. Reaction times to redundant targets significantly violated therace model inequality (Miller, 1982), but only when there was constancy of the target-defining dimension(s) within trial blocks. In Experiment 2, there was dimensional variability within blocks. Consistent with Experiment 1, constancy of the target-defining dimension(s), but this time across successive trials (rather than within blocks), was critical for observing violations of the race model inequality. These results provide evidence for parallel-coactive processing of multiple dimensions, consistent with thedimension-weighting account of Müller, Heller, and Ziegler (1995).     

The effect of previous trial type on inhibition of return

Inhibition of return (IOR) refers to the finding that targets appearing at previously cued locations are more slowly responded to than targets appearing at previously uncued locations when a relatively long temporal interval occurs between the cue and target. This experiment was conducted to determine whether the magnitude of IOR is influenced by the type of preceding trial (cued or uncued) and/or the location of the cue/target on the previous trial. Although no effect of cue/target location is observed, there was a marked effect of previous trial type, as IOR was greater following an uncued trial relative to a cued trial. This effect was attributable to differences in the response time as a function of previous trial type: specifically, participants were faster to respond to cued and uncued trials when the previous trial type was identical.     

Negative priming without reaction time: Effects on identification of masked letters

Responses to an object are often slower and/or less accurate if that object is related to a recently ignored object. Thisnegative priming effect has previously been examined only in reaction time tasks. In the present experiment, target letters and flanking distractor letters were displayed for 33, 100, or 300 msec, followed by a pattern mask. Subjects attempted to identify the target letters, with no demand for speed. Identification accuracy was reduced for targets that matched distractors presented on the immediately preceding trial. However, there was no bias against reporting preceding distractors on catch trials with no presented target. Implications for theories of negative priming are discussed.     

Tests of the duomemory notion for movement information

The validity of the duomemory notion (i.e. the concept of two separate memory systems, one for recently presented events and another for learned acts) for motor behavior was tested in an experiment which sought to determine the extent to which interference differentially influenced the recall of a movement when it is initially experienced and after it is repeatedly practiced. Using a traditional linear-positioning task, subjects moved to five defined target locations on each trial and after a retention interval attempted to recall the targets in reverse order. One location was repeated on each of 10 trials while the others were always different. Control subjects were presented and recalled only the repeated criterion location on each trial. The results indicated (a) a constant superiority of criterion recall accuracy for the control condition throughout the 10 trials and (b) and absence of improvement over practice by the experimental group in the recall of the criterion location relative to that of nonrepeated targets. The findings were interpreted as a lack of support for the duomemory notion, and the exploration of an alternative framework (Craik & Lockhart, 1972) for the investigation of memory for movement information was suggested.     

Sequence effects in a spatial cueing task: Endogenous orienting is sensitive to orienting in the preceding trial

In a spatial cueing paradigm it was investigated whether endogenous orienting is sensitive to orienting processes in the previous trial. Specifically, the effect of the previous cue direction, the previous trial type (valid, invalid, neutral, catch) and target alternation effects were studied. Strategic effects were shown as attentional costs and benefits were larger after a valid than after an invalid trial. Following catch trials, an overall response slowing was observed, but costs and benefits were unaffected. This was interpreted as a reduction in alertness and as support for the dissociation between spatial and temporal attentional mechanisms. Repetition of target position per se had no effect, but in neutral trials responses were slower to targets appearing at the location that was cued in the previous trial, independent of validity of the preceding trial. This suggests that long-term inhibition-of-return can occur between trials when attention is controlled endogenously.     

Inserting mastered targets during error correction when teaching skills to children with autism

Research has identified a variety of effective approaches for responding to errors during discrete‐trial training. In one commonly used method, the therapist delivers a prompt contingent on the occurrence of an incorrect response and then re‐presents the trial so that the learner has an opportunity to perform the correct response independently. Some authors recommend inserting trials with previously mastered targets between the prompted response and opportunities to respond independently, but no studies have directly examined the benefits of this approach. In this study, we manipulated the placement of trials with mastered targets during discrete‐trial training to compare the effectiveness of error correction with and without this recommended insertion procedure. Four children with autism participated, and each was taught 18 targets across 3 target sets. Results indicated that embedding trials with mastered targets into error correction may not confer benefits for most children and that doing so may lead to less efficient instruction.     

试次历史对跨通道非空间返回抑制的影响

个体对刺激的反应不仅受刺激本身的影响, 还会受到先前刺激的影响, 表现为对当前试次中刺激的反应会受到前一试次的影响, 即试次历史。本研究采用“线索-中性线索-靶子”范式探讨前一试次有效性对跨通道的非空间返回抑制的影响。实验1通过连续两个试次间的线索有效性考察在跨通道非空间返回抑制中试次历史的影响。为了在跨通道非空间返回抑制中减小试次历史的影响, 实验2通过延长试次间时间间隔考察跨通道非空间返回抑制中试次历史的作用是否减小。结果发现, 前一试次线索无效时, 当前试次中的返回抑制效应量显著小于前一试次有效时, 这种影响会根据试次中线索和靶子通道的不同而不同。并且当延长试次间的时间间隔可以有效地减少前一试次对当前试次的影响。因此本研究表明, 试次历史能够对跨通道非空间返回抑制产生影响, 并且这种影响可以通过增大试次间时间间隔来减小。     

Effects of competition on video-task performance in monkeys (Macaca mulatta)

The effects of competition on performance of a video-formatted task were examined in a series of experiments. Two rhesus monkeys (Macaca mulatta) were trained to manipulate a joystick to shoot at moving targets on a computer screen. The task was made competitive by requiring both animals to shoot at the same target and by rewarding only the animal that hit the target first each trial. The competitive task produced a significant and robust speed-accuracy trade-off in performance. The monkeys hit the target in significantly less time on contested than on uncontested trials. However, they required significantly more shots to hit the target on contested trials in relation to uncontested trials. This effect was unchanged when various schedules of reinforcement were introduced in the uncontested trials. This supports the influence of competition qua competition on performance, a point further bolstered by other findings of of behavioral contrast presented here.     

Interference and negative priming from ignored distractors: The role of selection difficulty

The relation between distractor interference and negative priming from identical distractors was examined in two experiments. Subjects responded to a target letter, which was indicated by an adjacent bar marker, and attempted to ignore a distracting letter. Onprime trials, distracting letters were either compatible or incompatible with the target, allowing for a measure of interference. On subsequentprobe trials, previously ignored distractors were sometimes presented as targets, allowing for a measure of negative priming. Reducing the spatial separation between targets and distractors on the prime trial increased the magnitude of interferenceand negative priming, but these effects appeared to be independent of each other (Experiment 1). In Experiment 2, the prime target location was precued on some trials, but not on others. Precuing attenuated the magnitude of interference, but not that of negative priming effects. This pattern indicates that measures of negative priming and measures of distractor interference on the immediately preceding trial are independent. The results are discussed in terms of a selective inhibition model of selective attention.     

Stimulus-determined discrimination mechanisms for color search.

Visual attention can be goal driven, stimulus driven, or a combination of the two. Here we report evidence for an unexpectedly stimulus-driven component of visual search for a target defined by color. Observers demonstrated a surprisingly cost-free ability to incorporate multiple classifiers in search for a target of one color from among distractors of other colors. A target color was presented among distractors that could change from trial to trial (intermixed presentation) or that remained constant across all trials in a block (blocked presentation). For blocked presentation, a single search classifier (a mechanism that segregates the target from distractors in color space) could be adopted, whereas for intermixed presentation different classifiers had to be used when the distractor colors changed. The benefit of blocked presentation was very small, suggesting that the appropriate classifier was determined very quickly in trials for which the classifier changed. The results suggest that the stimulus-driven activation of an appropriate stimulus classifier can be very efficient.     

Stimulus-determined discrimination mechanisms for color search

Visual attention can be goal driven, stimulus driven, or a combination of the two. Here we report evidence for an unexpectedly stimulus-driven component of visual search for a target defined by color. Observers demonstrated a surprisingly cost-free ability to incorporate multiple classifiers in search for a target of one color from among distractors of other colors. A target color was presented among distractors that could change from trial to trial (intermixed presentation) or that remained constant across all trials in a block (blocked presentation). For blocked presentation, a single search classifier (a mechanism that segregates the target from distractors in color space) could be adopted, whereas for intermixed presentation different classifiers had to be used when the distractor colors changed. The benefit of blocked presentation was very small, suggesting that the appropriate classifier was determined very quickly in trials for which the classifier changed. The results suggest that the stimulus-driven activation of an appropriate stimulus classifier can be very efficient.     

Inhibition from semantically related primes: Evidence of a category-specific inhibition

The phenomenon of inhibition from generating successive items within a category, reported by A. S. Brown (1981), was examined in two experiments. Subjects responded on target trials by either generating targets (e.g., generating BASS to B when it followed the category name FISH, Experiment 1) or reading them (reading BASS when it followed the category name FISH, Experiment 2). Prior to target trials, all subjects received priming trials consisting of either one or four exemplars from a single semantic category, which could be either the same category as the target’s category (related priming condition) or an unrelated category (unrelated priming condition). In both experiments, different groups of subjects either read or generated primes. When primes were read, target response times (RTs) were always facilitated in the related priming condition compared with in the unrelated priming condition. However, when primes were generated, this facilitation from related primes was eliminated, except in the one-prime condition, when targets were also generated. When primes and targets were both generated, RTs in the related priming condition were slower following four primes than following one prime. Thus, category-specific inhibition from multiple related primes is greatest when both primes and targets must be actively retrieved.