Validation of a rodent model of episodic memory replay.

Vivid episodic memories in humans have been described as the replay of the flow of past events in sequential order. Recently, Panoz-Brown et al. Current Biology, 28, 1628-1634, (2018) developed an olfactory memory task in which rats were presented with a list of trial-unique odors in an encoding context; next, in a distinctive memory assessment context, the rats were rewarded for choosing the second to last item from the list while avoiding other items from the list. In a different memory assessment context, the fourth to last item was rewarded. According to the episodic memory replay hypothesis, the rat remembers the list items and searches these items to find the item at the targeted locations in the list. However, events presented sequentially differ in memory trace strength, allowing a rat to use the relative familiarity of the memory traces, instead of episodic memory replay, to solve the task. Here, we directly manipulated memory trace strength by manipulating the odor intensity of target odors in both the list presentation and memory assessment. The rats relied on episodic memory replay to solve the memory assessment in conditions in which reliance on memory trace strength is ruled out. We conclude that rats are able to replay episodic memories.

Function estimation: Quantifying individual differences of hand-drawn functions.

Graphical perception is an important part of the scientific endeavour, and the interpretation of graphical information is increasingly important among educated consumers of popular media, who are often presented with graphs of data in support of different policy positions. However, graphs are multidimensional and data in graphs are comprised not only of overall global trends but also local perturbations. We presented a novel function estimation task in which scatterplots of noisy data that varied in the number of data points, the scale of the data, and the true generating function were shown to observers. 170 psychology undergraduates with mixed experience of mathematical functions were asked to draw the function that they believe generated the data. Our results indicated not only a general influence of various aspects of the presented graph (e.g., increasing the number of data points results in smoother generated functions) but also clear individual differences, with some observers tending to generate functions that track the local changes in the data and others following global trends in the data.

Recognition memory decisions made with short- and long-term retrieval.

In the present research, we produce a coherent account of the storage and retrieval processes in short- and long-term event memory, and long-term knowledge, that produce response accuracy and response time in a wide variety of conditions in our studies of recognition memory. Two to nine pictures are studied sequentially followed by a target or foil test picture in four conditions used in Nosofsky et al. Journal of Experimental Psychology: Learning, Memory, and Cognition, 47, 316-342, (2021) and in our new paradigm: VM: target and foil responses to a given stimulus change from trial to trial; CM: the responses do not change from trial to trial; AN: every trial uses new stimuli; MIXED: combinations of VM, CN, and AN occur on each trial. In the new paradigm a given picture is equally often tested as old or new, but only in CM is the response key the same and learnable. Our model has components that have appeared in a variety of prior accounts, including learning and familiarity, but are given support by our demonstration that accuracy and response time data from a large variety of conditions can be predicted by these processes acting together, with parameter values that largely are unchanged. A longer version of this article, containing information not found here due to space, is available online  https://doi.org/10.31234/osf.io/h8msp .The avalibility of the data (supplement materials), info and link is attached at the end section ( https://psyarxiv.com/h8msp .).

Against naïve induction from experimental data.

This commentary argues against the indictment of current experimental practices such as piecemeal testing, and the proposed integrated experiment design (IED) approach, which we see as yet another attempt at automating scientific thinking. We identify a number of undesirable features of IED that lead us to believe that its broad application will hinder scientific progress.

The distinction between long-term knowledge and short-term control processes is valid and useful.

The binary distinction De Neys questions has been put forward many times since the beginnings of psychology, in slightly different forms and under different names. It has proved enormously useful and has received detailed empirical support and careful modeling. At heart the distinction is that between knowledge in long-term memory and control processes in short-term memory.

Extraordinary claims, extraordinary evidence? A discussion.

Roberts (2020, Learning & Behavior, 48[2], 191-192) discussed research claiming honeybees can do arithmetic. Some readers of this research might regard such claims as unlikely. The present authors used this example as a basis for a debate on the criterion that ought to be used for publication of results or conclusions that could be viewed as unlikely by a significant number of readers, editors, or reviewers.

Scientific progress despite irreproducibility: A seeming paradox.

It appears paradoxical that science is producing outstanding new results and theories at a rapid rate at the same time that researchers are identifying serious problems in the practice of science that cause many reports to be irreproducible and invalid. Certainly, the practice of science needs to be improved, and scientists are now pursuing this goal. However, in this perspective, we argue that this seeming paradox is not new, has always been part of the way science works, and likely will remain so. We first introduce the paradox. We then review a wide range of challenges that appear to make scientific success difficult. Next, we describe the factors that make science work-in the past, present, and presumably also in the future. We then suggest that remedies for the present practice of science need to be applied selectively so as not to slow progress and illustrate with a few examples. We conclude with arguments that communication of science needs to emphasize not just problems but the enormous successes and benefits that science has brought and is now bringing to all elements of modern society.

What are the appropriate axioms of rationality for reasoning under uncertainty with resource-constrained systems?

When constrained by limited resources, how do we choose axioms of rationality? The target article relies on Bayesian reasoning that encounter serious tractability problems. We propose another axiomatic foundation: quantum probability theory, which provides for less complex and more comprehensive descriptions. More generally, defining rationality in terms of axiomatic systems misses a key issue: rationality must be defined by humans facing vague information.

50 years of research sparked by Atkinson and Shiffrin (1968).

In this article we review the framework proposed in 1968 by Atkinson and Shiffrin. We discuss the prior context that led to its production, including the advent of cognitive and mathematical modeling, its principal concepts, the subsequent refinements and elaborations that followed, and the way that the framework influenced other researchers to test the ideas and, in some cases, propose alternatives. The article illustrates the large amount of research and the large number of memory models that were directly influenced by this chapter over the past 50 years.

Item frequency in probe-recognition memory search: Converging evidence for a role of item-response learning.

In short-term probe-recognition tasks, observers make speeded old-new recognition judgments for items that are members of short lists. However, long-term memory (LTM) for items from previous lists influences current-list performance. The current experiment pursued the nature of these long-term influences-in particular, whether they emerged from item-familiarity or item-response-learning mechanisms. Subjects engaged in varied-mapping (VM) and consistent-mapping (CM) short-term probe-recognition tasks (e.g., Schneider & Shiffrin, Psychological Review, 84, 1-66, 1977). The key manipulation was to vary the frequency with which individual items were presented across trials. We observed a striking dissociation: Whereas increased presentation frequency led to benefits in performance for both old and new test probes in CM search, it resulted in interference effects for both old and new test probes in VM search. Formal modeling suggested that a form of item-response learning took place in both conditions: Each presentation of a test probe led to the storage of that test probe-along with its associated "old" or "new" response-as an exemplar in LTM. These item-response pairs were retrieved along with current-list items in driving observers' old-- recognition judgments. We conclude that item-response learning is a core component of the LTM mechanisms that influence CM and VM memory search.

Models that allow us to perceive the world more accurately also allow us to remember past events more accurately via differentiation.

Differentiation is a theory that originally emerged from the perception literature and proposes that with experience, the representation of stimuli becomes more distinct from or less similar to the representation of other stimuli. In recent years, the role of differentiation has played a critical role in models of memory. Differentiation mechanisms have been implemented in episodic memory models by assuming that information about new experiences with a stimulus in a particular context accumulates in a single memory trace and these updated memory traces become more distinct from the representations of other stimuli. A key implication of such models is that well encoded events are less confusable with other events. This prediction is particularly relevant for two important phenomena. One is the role of encoding strength on memory. The strength based mirror effect is the finding of higher hit rates and lower false alarm rates for a list composed of all strongly encoded items compared to a list composed of all weakly encoded items. The other is output interference, the finding that accuracy decreases across a series of test trials. Results from four experiments show a tight coupling between these two empirical phenomena such that strongly encoded target items are less prone to interference. By proposing a process model and evaluating the predictions of the model, we show how a single theoretical principle, differentiation, provides a unified explanation for these effects.

Context effects produced by question orders reveal quantum nature of human judgments.

The hypothesis that human reasoning obeys the laws of quantum rather than classical probability has been used in recent years to explain a variety of seemingly "irrational" judgment and decision-making findings. This article provides independent evidence for this hypothesis based on an a priori prediction, called the quantum question (QQ) equality, concerning the effect of asking attitude questions successively in different orders. We empirically evaluated the predicted QQ equality using 70 national representative surveys and two laboratory experiments that manipulated question orders. Each national study contained 651-3,006 participants. The results provided strong support for the predicted QQ equality. These findings suggest that quantum probability theory, initially invented to explain noncommutativity of measurements in physics, provides a simple account for a surprising regularity regarding measurement order effects in social and behavioral science.

Salience, Perceptual Dimensions, and the Diversion of Attention.

Parallel and automatic processing is evidenced in visual search by what is commonly called popout. An object of search (a target) that differs widely from all other display objects on some simple visual dimension is commonly called a singleton; an example is search for a red circle when all other displayed circles are green. A singleton attracts attention to the degree that it is salient, and highly salient singletons produce search that is almost independent of display size. The present research examines the way this attraction of attention can be diverted by the presence of singletons on 1 or 2 nontarget perceptual dimensions (e.g., search for a red circle among green ones, when one of the green circles is larger than the others, and another might be green but square). The results establish that distraction occurs rarely but strongly, that 2 distractors produce more distraction than 1, and that the degree of distraction depends not only on salience but also on dimension similarity. These findings occurred in 2 different tasks: The observer either reported the orientation of a Gabor embedded in the target or reported the presence and absence of the target.

Familiarity and categorization processes in memory search.

A fundamental distinction in tasks of memory search is whether items receive varied mappings (targets and distractors switch roles across trials) or consistent mappings (targets and distractors never switch roles). The type of mapping often produces markedly different performance patterns, but formal memory-based models that account quantitatively for detailed aspects of the results have not yet been developed and evaluated. Experiments were conducted to test a modern exemplar-retrieval model on its ability to account for memory-search performance involving a wide range of memory-set sizes in both varied-mapping (VM) and consistent-mapping (CM) probe-recognition tasks. The model formalized the idea that both familiarity-based and categorization-based processes operate. The model was required to fit detailed response-time (RT) distributions of individual, highly practiced subjects. A key manipulation involved the repetition of negative probes across trials. This manipulation produced a dramatic dissociation: False-alarm rates increased and correct-rejection RTs got longer in VM, but not in CM. The qualitative pattern of results and modeling analyses provided evidence for a strong form of categorization-based processing in CM, in which observers made use of the membership of negative probes in the "new" category to make old-new recognition decisions.

Stereotype threat prevents perceptual learning.

Stereotype threat (ST) refers to a situation in which a member of a group fears that her or his performance will validate an existing negative performance stereotype, causing a decrease in performance. For example, reminding women of the stereotype "women are bad at math" causes them to perform more poorly on math questions from the SAT and GRE. Performance deficits can be of several types and be produced by several mechanisms. We show that ST prevents perceptual learning, defined in our task as an increasing rate of search for a target Chinese character in a display of such characters. Displays contained two or four characters and half of these contained a target. Search rate increased across a session of training for a control group of women, but not women under ST. Speeding of search is typically explained in terms of learned "popout" (automatic attraction of attention to a target). Did women under ST learn popout but fail to express it? Following training, the women were shown two colored squares and asked to choose the one with the greater color saturation. Superimposed on the squares were task-irrelevant Chinese characters. For women not trained under ST, the presence of a trained target on one square slowed responding, indicating that training had caused the learning of an attention response to targets. Women trained under ST showed no slowing, indicating that they had not learned such an attention response.

Overcoming the negative consequences of interference from recognition memory testing.

Theories of why humans forget have been challenged by the newly discovered list-length/output-interference paradox, in which--under certain testing conditions--learning is not harmed by the amount of verbal material studied, whereas retrieval of that material becomes more difficult with increases in the number of items tested. The latter finding is known as output interference, and the results of the experiment reported here indicate that a release from output interference is obtained when the nature of the items is changed during testing. Specifically, when participants are asked to recognize items from two categories, output interference is minimized when items from each category are tested separately in large blocks. This finding supports models of forgetting that assume interference arises from information about the to-be-learned material that is stored in memory; in contrast, this finding is difficult to explain using models that assume forgetting is the result only of changing context.

Is it Reasonable to Study Decision-Making Quantitatively?

Scientists studying decision-making often provide a set of choices, each specified with values or distributions of values, and probabilities or distributions of probabilities. For example, "Would you prefer $100 with probability 1.0 or $1 with probability .9 and $1,000 with probability 0.1?" Other decision research examines choices made in the absence of most quantitative information; for example, "Would you prefer a Ford now or a Porsche a year from now?," "Which food would you prefer," but models the findings with precise quantitative assumptions. Yet other research does neither; for example, modeling verbally stated choices with verbally stated heuristics. This article asks about the relevance of the first two research approaches for much of the decision-making made in life. The use of quantitative research and modeling is unsurprising, given that this approach underlies most of science. In life, values and probabilities are almost always partly or wholly vague and qualitative rather than quantitative. For example, when deciding which house to buy, there are relevant features such as size, color, neighborhood schools, construction materials, attractiveness, and many more, but the decision-maker finds it difficult and of little use to assign these precise values or weights. Nonetheless, humans have evolved to make decisions in such vaguely specified settings. I provide an example showing how a very high degree of uncertainty can defeat the application of quantitative decision-making, but such a demonstration is not critical if quantitative research and modeling produce a good understanding of and a good approximation to decision-making in the natural environment. This perspective addresses these issues.