Is information reduction an item‐specific or an item‐general process?

Visual gaze patterns in trainee endoscopists - a novel assessment tool

BACKGROUND

Colonoscopy proficiency is significantly influenced by skills achieved during training. Although assessment scores exist, they do not evaluate the impact of visual search strategies and their use is time and labour intensive. Eye-tracking has shown significant differences in visual gaze patterns (VGPs) between expert endoscopists with varying polyp detection rates, so may provide a means of automated assessment and guidance for trainees. This study aimed to assess the feasibility of eye-tracking as a novel assessment method for trainee endoscopists.

METHODS

Eye-tracking glasses were used to record 26 colonoscopies from 12 endoscopy trainees who were assessed with directly observed procedural scores (DOPS), devised by the Joint Advisory Group (JAG) on GI endoscopy, and a visual analogue score of overall competence. A 'total weighted procedure score' (TWPS) was calculated from 1 to 20. Primary outcomes of fixation duration (FixD) and fixation frequency (FixF) were analysed according to areas of interest (AOIs) with the bowel surface and lumen represented by three concentric rings. Correlation was assessed using Pearson's coefficient. Significance was set at p<.050.

RESULTS

Trainees displayed a significant positive correlation between TWPS and FixD (R = 0.943, p<.0001) and FixF (R = 0.936, p<.0001) in the anatomical bowel mucosa peripheries. Conversely, they had significant negative correlations between TWPS and the anatomical bowel lumen (FixD: R= -0.546, p=.004; FixF: R= -0.568, p=.002).

CONCLUSIONS

Higher objective performance scores were associated with VGPs focussing on bowel mucosa. This is consistent with prior analysis showing peripheral VGPs correspond with higher polyp detection rates. Analysis of VGPs, therefore, has potential for training and assessment in colonoscopy.

Comparison of gaze behaviour of trainee and experienced surgeons during laparoscopic gastric bypass

Background

Eye tracking presents a novel tool that could be used to profile skill levels in surgery objectively. The primary aim of this study was to identify differences in gaze behaviour between expert and junior surgeons performing a laparoscopic Roux-en-Y gastric bypass (LRYGB) for obesity.

Methods

This prospective observational study used a lightweight eye-tracking apparatus to determine the difference in gaze behaviours between expert (more than 75 procedures) and junior (75 or fewer procedures) surgeons at defined stages of LRYGB. Primary endpoints were normalized dwell time and fixation frequency. Secondary endpoints were blink rate, maximum pupil size and rate of pupil change.

Results

A total of 20 procedures (12 junior, 8 expert) were analysed. Compared with juniors, experts showed a prolonged dwell time on the screen during angle of His dissection (median (range) 91·20 (83·40–94·40) versus 68·95 (59·80–87·60) per cent; P = 0·001), formation of the retrogastric tunnel (91·50 (85·80–95·50) versus 73·60 (34·60–90·50) per cent; P = 0·001) and gastric pouch formation (86·95 (83·60–90·20) versus 67·60 (37·10–80·00) per cent P &lt; 0·001). Juniors had a greater blink frequency throughout all recorded segments (P &lt; 0·010) and had a larger maximum pupil size during all recorded operative segments (P &lt; 0·010). Rate of pupil change was greater in juniors in all analysed segments (P &lt; 0·010).

Conclusion

These results suggest that experts display more focused attention on significant stimuli, alongside experiencing a reduced mental workload and having increased concentration. This has the potential for future use in validation of surgical skill in high-stakes assessment.

Once and for all—How people change strategy to ignore irrelevant information in visual tasks

Ignoring irrelevant visual information aids efficient interaction with task environments. We studied how people, after practice, start to ignore the irrelevant aspects of stimuli. For this we focused on how information reduction transfers to rarely practised and novel stimuli. In Experiment 1, we compared competing mathematical models on how people cease to fixate on irrelevant parts of stimuli. Information reduction occurred at the same rate for frequent, infrequent, and novel stimuli. Once acquired with some stimuli, it was applied to all. In Experiment 2, simplification of task processing also occurred in a once-for-all manner when spatial regularities were ruled out so that people could not rely on learning which screen position is irrelevant. Apparently, changes in eye movements were an effect of a once-for-all strategy change rather than a cause of it. Overall, the results suggest that participants incidentally acquired knowledge about regularities in the task material and then decided to voluntarily apply it for efficient task processing. Such decisions should be incorporated into accounts of information reduction and other theories of strategy change in skill acquisition.

Transferring control demands across incidental learning tasks - stronger sequence usage in serial reaction task after shortcut option in letter string checking

After incidentally learning about a hidden regularity, participants can either continue to solve the task as instructed or, alternatively, apply a shortcut. Past research suggests that the amount of conflict implied by adopting a shortcut seems to bias the decision for vs. against continuing instruction-coherent task processing. We explored whether this decision might transfer from one incidental learning task to the next. Theories that conceptualize strategy change in incidental learning as a learning-plus-decision phenomenon suggest that high demands to adhere to instruction-coherent task processing in Task 1 will impede shortcut usage in Task 2, whereas low control demands will foster it. We sequentially applied two established incidental learning tasks differing in stimuli, responses and hidden regularity (the alphabet verification task followed by the serial reaction task, SRT). While some participants experienced a complete redundancy in the task material of the alphabet verification task (low demands to adhere to instructions), for others the redundancy was only partial. Thus, shortcut application would have led to errors (high demands to follow instructions). The low control demand condition showed the strongest usage of the fixed and repeating sequence of responses in the SRT. The transfer results are in line with the learning-plus-decision view of strategy change in incidental learning, rather than with resource theories of self-control.

Playing off the curve - testing quantitative predictions of skill acquisition theories in development of chess performance

Learning curves have been proposed as an adequate description of learning processes, no matter whether the processes manifest within minutes or across years. Different mechanisms underlying skill acquisition can lead to differences in the shape of learning curves. In the current study, we analyze the tournament performance data of 1383 chess players who begin competing at young age and play tournaments for at least 10 years. We analyze the performance development with the goal to test the adequacy of learning curves, and the skill acquisition theories they are based on, for describing and predicting expertise acquisition. On the one hand, we show that the skill acquisition theories implying a negative exponential learning curve do a better job in both describing early performance gains and predicting later trajectories of chess performance than those theories implying a power function learning curve. On the other hand, the learning curves of a large proportion of players show systematic qualitative deviations from the predictions of either type of skill acquisition theory. While skill acquisition theories predict larger performance gains in early years and smaller gains in later years, a substantial number of players begin to show substantial improvements with a delay of several years (and no improvement in the first years), deviations not fully accounted for by quantity of practice. The current work adds to the debate on how learning processes on a small time scale combine to large-scale changes.

The Einstellung effect in anagram problem solving: evidence from eye movements

The Einstellung effect is the counterintuitive finding that prior experience or domain-specific knowledge can under some circumstances interfere with problem solving performance. This effect has been demonstrated in several domains of expertise including medicine and chess. In the present study we explored this effect in the context of a simplified anagram problem solving task. Participants solved anagram problems while their eye movements were monitored. Each problem consisted of six letters: a central three-letter string whose letters were part of the solution word, and three additional individual letters. Participants were informed that one of the individual letters was a distractor letter and were asked to find a five-letter solution word. In order to examine the impact of stimulus familiarity on problem solving performance and eye movements, the central letter string was presented either as a familiar three-letter word, or the letters were rearranged to form a three-letter nonword. Replicating the classic Einstellung effect, overall performance was better for nonword than word trials. However, participants’ eye movements revealed a more complex pattern of both interference and facilitation as a function of the familiarity of the central letter string. Specifically, word trials resulted in shorter viewing times on the central letter string and longer viewing times on the individual letters than nonword trials. These findings suggest that while participants were better able to encode and maintain the meaningful word stimuli in working memory, they found it more challenging to integrate the individual letters into the central letter string when it was presented as a word.

Learning what from where: Effects of spatial regularity on nonspatial sequence learning and updating

The current study examined the influence of redundant stimulus features on our ability to build and update representations of our environment. We hypothesized that our ability to process redundant spatial features would speed our ability to adapt to changing nonspatial regularities. Using a computerized version of the children's game "rock-paper-scissors", undergraduates were instructed to win as often as possible against a computer opponent. The computer's plays were repeating sequences of five choices that were presented either with spatial regularity (i.e., "rock" would always appear on the left, "paper" in the middle, and "scissors" on the right) or without spatial regularity (i.e., the items were equally likely to appear in any of the three locations). Once participants learned a sequence, the computer switched to a different sequence without participants being informed that a switch had occurred. Redundant spatial regularity improved a participant's ability both to learn sequences of plays and to update their plays to reflect new computer sequences. Our results suggest that our perceptual system is sensitive to redundant spatial stimulus features and that this information can improve learning and updating.

Effects of shopping addiction on consumer decision-making: Web-based studies in real time

Background and aims Most research into compulsive buying has focused on its causes: questionnaires have been used to study its association with various factors assumed to be important in its etiology. Few studies have dealt with the effects of being a compulsive buyer on shopping decisions. Also, processes underlying compulsive buying are dynamic but questionnaires give access only to a retrospective view of them from the standpoint of the participant. The aim of the current study was to investigate the decision processes underlying compulsive buying. Methods Two simulated shopping experiments, each with over 100 participants, were used to compare the decision processes of compulsive shoppers with those of non-compulsive shoppers. This approach allowed us to measure many features of consumer decision-making that are relevant to compulsive shopping. Results Compulsive shoppers differed from general shoppers in six ways: choice characteristics, searching behavior, overspending, budget-consciousness, effects of credit card availability, and emotional responses to overspending. Conclusions Results are consistent with the view that compulsive buying, like other behavioral addictions, develops because the cognitive system under-predicts the extent of post-addiction craving produced by emotional and visceral processes.