Simple contextual cueing prevents retroactive interference in short-term perceptual training of orientation detection tasks

Perceptual training of multiple tasks suffers from interference between the trained tasks. Here, we conducted four psychophysical experiments with separate groups of participants to investigate the possibility of preventing the interference in short-term perceptual training. We trained the participants to detect two orientations of Gabor stimuli in two adjacent days at the same retinal location and examined the interference of training effects between the two orientations. The results showed significant retroactive interference from the second orientation to the first orientation (Experiments 1 and 2). Introducing a 6-hour interval between the pre-test and training of the second orientation did not eliminate the interference effect, excluding the interpretation of disrupted reconsolidation as the pre-test of the second orientation may reactivate and destabilize the representation of the first orientation (Experiment 3). Finally, the training of the two orientations was accompanied by fixations in two colors, each served as a contextual cue for one orientation. The results showed that the retroactive interference was not evident after introducing these passively perceived contextual cues (Experiment 4). Our findings suggest that the retroactive interference effect in short-term perceptual training of orientation detection tasks was likely the result of higher-level factors such as shared contextual cues embedded in the tasks. The effect of multiple perceptual training could be facilitated by associating the trained tasks with different contextual cues.

Context, attention, and the switch between habit and goal-direction in behavior

This article reviews recent findings from the author’s laboratory that may provide new insights into how habits are made and broken. Habits are extensively practiced behaviors that are automatically evoked by antecedent cues and performed without their goal (or reinforcer) “in mind.” Goal-directed actions, in contrast, are instrumental behaviors that are performed because their goal is remembered and valued. New results suggest that actions may transition to habit after extended practice when conditions encourage reduced attention to the behavior. Consistent with theories of attention and learning, a behavior may command less attention (and become habitual) as its reinforcer becomes well-predicted by cues in the environment; habit learning is prevented if presentation of the reinforcer is uncertain. Other results suggest that habits are not permanent, and that goal-direction can be restored by several environmental manipulations, including exposure to unexpected reinforcers or context change. Habits are more context-dependent than goal-directed actions are. Habit learning causes retroactive interference in a way that is reminiscent of extinction: It inhibits, but does not erase, goal-direction in a context-dependent way. The findings have implications for the understanding of habitual and goal-directed control of behavior as well as disordered behaviors like addictions.

Association of physical activity on memory interference: Boston Puerto Rican Health Study

Background: The objective of this study was to evaluate the association between habitual physical activity engagement on memory interference. The present analysis used cross-sectional data from the Boston Puerto Rican Health Study (n=1,241; mean age= 57.2; 72.1% female). Methods: Physical activity was evaluated via self-report. Memory interference was evaluated using a word-list paradigm. The memory task included learning a list of 16 words (List A; 5 trials), followed by a distractor list (List B), and then an immediate recall of List A. Proactive interference occurs when preceding stimuli (e.g., Trial 1 and Trial 5 of List A) interferes with performance on a subsequent stimuli (List B). Retroactive interference occurs when subsequent stimuli (List B) interferes with the recall of previously encoded stimuli (Trial 5). Results: For proactive interference, there was no association between physical activity and the difference between performance on List B and Trial 1 of List A (β=0.00001; P=0.96). Similarly, for retroactive interference, there was no association between physical activity and the difference between the short delay recall and Trial 5 of List A (β=0.0002; P=0.50). Conclusion: The present study did not observe an association between habitual physical activity on attenuating memory interference.

Retroactive interference model of forgetting

Memory and forgetting constitute two sides of the same coin, and although the first has been extensively investigated, the latter is often overlooked. A possible approach to better understand forgetting is to develop phenomenological models that implement its putative mechanisms in the most elementary way possible, and then experimentally test the theoretical predictions of these models. One such mechanism proposed in previous studies is retrograde interference, stating that a memory can be erased due to subsequently acquired memories. In the current contribution, we hypothesize that retrograde erasure is controlled by the relevant “importance” measures such that more important memories eliminate less important ones acquired earlier. We show that some versions of the resulting mathematical model are broadly compatible with the previously reported power-law forgetting time course and match well the results of our recognition experiments with long, randomly assembled streams of words.