Christoph Stahl (Herbert-Lewin-Str. 2, 50674 Cologne, Germany. E-mail:
Handling editor: Robert Balas (Polish Academy of Sciences, Warsaw, Poland)
The article proposes a view of evaluative conditioning (EC) as resulting from judgments based on learning instances stored in memory. It is based on the formal episodic memory model MINERVA 2. Additional assumptions specify how the information retrieved from memory is used to inform specific evaluative dependent measures. The present approach goes beyond previous accounts in that it uses a well-specified formal model of episodic memory; it is however more limited in scope as it aims to explain EC phenomena that do not involve reasoning processes. The article illustrates how the memory-based-judgment view accounts for several empirical findings in the EC literature that are often discussed as evidence for dual-process models of attitude learning. It sketches novel predictions, discusses limitations of the present approach, and identifies challenges and opportunities for its future development.
This article is part of SPB's special issue on “
Evaluative conditioning (EC) effects can be understood as resulting from judgments based on the contents of episodic memory. The basic assumption of this view is that EC—especially when incidentally learned—can be explained by current single-process models of episodic memory, together with assumptions about how the information available in memory is used to inform the specific dependent measures with which EC is assessed. This
Learning about the evaluation of novel objects may proceed via domain-general propositional reasoning processes (
The present perspective has previously been proposed by other researchers who have suggested that dissociations in the EC literature may be explained not by dual learning but dual retrieval processes (e.g.,
The present account is located at a cognitive or algorithmic level of analysis (
The basic hypothesis is that EC is the result of a single learning (i.e., encoding) process that encodes and stores learning instances in declarative episodic memory, the contents of which can be retrieved to inform evaluative judgments (as well as other judgments and behaviors). A learning instance or episode binds together the information that is extracted from the current stimulus situation (i.e., the stimuli presented by the experimenter, the situational context, as well as internally generated information such as spontaneous ideosyncratic thoughts and impressions, or retrieval of prior knowledge or experience).
This hypothesis implies that all factors known to affect episodic memory across the encoding, maintenance, and retrieval stages are also potential influences on EC
The above considerations are not novel and they apply to episodic memory quite generally. Yet, in their joint application to the EC literature, they may prove sufficient to explain (most of) the EC phenomena that have puzzled researchers in the past and have prompted the (in our view unwarranted) postulation of dual learning processes. The specific perspective that we will outline below has been further informed by formal models of episodic memory, such as MINERVA 2 (
In the MINERVA 2 model, memory is a matrix, to which a row vector is added to represent a newly encoded episode (or instance). In this episode vector, each position or value represents a stimulus or context feature (e.g., color, valence, etc.) that can be either present (i.e., represented by +1), absent (-1), or unknown (0). During exposure, each individual feature is encoded with probability
The model can account for evaluative judgments as follows: Assume a CS-US co-occurrence episode is stored as a memory trace in the matrix (along with a number of episodes that contain neither the CS nor US). When cued with the CS, the newly stored trace will be highly activated, supporting recognition of the CS. As a result, the stored trace will enter the computation of the echo content with great weight, so that the other features of the episode (including, importantly, the US’s valence) will be recalled. The recalled valence can then inform evaluative judgments about the CS. In this sense, evaluative ratings can be considered a variant of cued recall.
As a general memory model, MINERVA 2 does not qualify the type of information that can be encoded. Specifically, it allows anything to be encoded that can be modeled by a vector of (binary) values; it is silent as to whether this information is an association or a proposition. This is not to say that it endorses the existence of distinct types of representations, but that a (single-process) episodic-memory model may serve as a container for simple as well as more complex contents.
The present view is therefore compatible with
We have applied the MINERVA 2 model to counterconditioning and extinction in EC (
So far, this is the only EC phenomenon that we have formally modeled with MINERVA 2. We are in the process of extending this formal approach to other EC phenomena. We believe that many (if not all) of the EC phenomena discovered so far can be explained by this model when combined with a few additional assumptions substantiated by independent research. Because MINERVA 2 is a
In the following sections, we illustrate how moderating factors identified in memory research that impact processing at the encoding, maintenance, and retrieval stages account for relevant findings in the EC literature as viewed from a memory-based-judgment perspective. To foreshadow, we address the
This section discusses what is stored in memory, the nature of the representation, the role of awareness at encoding, and the type of processes that may affect encoding of CS-US co-occurrence episodes. We also consider evidence regarding the parallel effects of encoding manipulations on EC and memory.
According to instance-based memory theories, memory consists of a collection of episodes. The content of an episode is thought of as the set of external and internal information that is processed during the small time period that constitutes the episode (
The contents of consciousness during an episode determine what is encoded into memory. These contents are themselves a function of bottom-up stimulus strength and top-down processing, as affected by attention and goals (
First, participants may fail to consciously perceive the CS-US co-occurrence episode, perhaps because only one of the stimuli was consciously perceived, whereas the second one was not perceived at all or only fragmentarily. Those (parts of the) stimuli that were perceived would be encoded jointly into a single memory episode. This case reflects
Second, participants may consciously perceive both the CS and US. The two stimuli are therefore part of the encoded episode. Yet, participants need not be aware of this fact (i.e., if their attention is directed entirely toward sensory experience, they can be aware of the stimuli themselves but not of their being aware of the stimuli). As a consequence, they can also be unaware of the co-occurrence of (or the association between) the CS and US. This case represents
Third, participants may have higher-order thoughts about the contents of their consciousness: Given that some amount of attention is directed toward their own mental state, they may be conscious of the fact that they currently perceive the CS and US as part of the same episode; or they may consciously expect to see a US of a specific valence given that they just have seen a specific CS. This third case is more likely under
In line with the PAL (
At encoding, we can distinguish influences due to properties of the stimulus situation (i.e., bottom-up effects) from influences due to properties of the cognitive system (top-down effects). For instance, bottom-up stimulus strength and top-down attention interact to determine the level of conscious processing (
Beyond top-down attention, the specific type of processing task during learning has also been shown to influence EC (e.g.,
Beyond stimulus strength, another bottom-up manipulation that affects encoding of CS-US pairs is their simultaneous versus sequential presentation: When both stimuli appear next to each other on the screen, they are more likely to be encoded as part of a single episode; in contrast, when they are presented sequentially one after another, memory traces are more likely to contain single stimuli instead of pairs. In line with a single encoding process, this affects not only EC but also explicit memory; both are increased for simultaneous as compared to sequential pairings (
In between encoding and retrieval, the encoded information is subject to intervening processes such as rehearsal or forgetting. In addition, retrospective integration has been proposed as an information-integration process that operates during maintenance.
Rehearsal processes that operate on the CS-US episodes may affect memory for these episodes and consequently later evaluation of the CS, because rehearsal episodes are also encoded into memory. Rehearsal may occur during the learning phase of a study as well as during subsequent stages. Considering that EC resembles a paired-associate learning situation, participants may attempt to retrieve the US associated with a CS during the learning phase, especially in an intentional learning situation using a sequential presentation schedule in which CSs are presented before USs with sufficient delay between stimulus presentations. Successfully recalling the US that was paired with a given CS constitutes in itself another episode in which the CS and US co-occur (if “only” in participants’ minds), which can strengthen memory for the pair. Similarly, recalling one’s own integrative evaluation of the CS during an intervening task can strengthen later evaluation of the CS (in other words, such rehearsal prepares an evaluative response and/or facilitates its later retrieval).
A related mechanism, termed
If not rehearsed, information stored in memory is forgotten over time (due to decay and/or retroactive interference). Forgetting may differently affect different aspects of the stimulus episode in a systematic way. For instance, forgetting occurs at a higher rate for more detailed, low-level (verbatim) information about a stimulus, whereas more abstract high-level (gist) information is retained over a longer time (e.g.,
The contents of memory constantly inform cognition and behavior, but different affordances of dependent measures may affect how information is retrieved and integrated in a specific situation and for a specific purpose (e.g.,
The information encoded into memory can be used in different ways by different dependent measures. Properties of dependent measures, such as their time limits and response requirements, may affect the amount and quality of information that is retrieved, and how it can be integrated and used to inform the dependent measure. Importantly, again, the present account predicts that such effects are comparable for memory and EC phenomena.
Deliberate evaluations are typically assessed using rating scales in unspeeded situations that allow for retrieval and careful integration of all available information in memory. In contrast, “automatic” evaluative responses are typically assessed using indirect measures (such as the IAT or affective priming task), which call for speeded binary classification decisions. Briefly, the information available in memory can be retrieved and integrated more reliably and in its entire complexity in unspeeded situations; in contrast, time pressure will reduce the fidelity of the retrieved information and interfere with its integration. These differences may produce empirical dissociations if, in addition to the CS and US, additional detail (such as relational qualifiers) needs to be retrieved and integrated with US valence information before a summary evaluation can be generated that can inform the dependent measure. Under these conditions, the speeded measure should be less likely to reflect the additional information than the unspeeded measure. Such a pattern has been observed in several studies, and we argue that it arises at retrieval as a function of the properties of the different dependent measures (
A well-established retrieval dissociation is that people can readily control the expression of their attitudes and prejudices when filling out a survey, but such control requires much more effort (as well as task-specific knowledge and strategies) on indirect measures such as affective priming tasks (
This interpretation implies that indirect measures are not necessarily a more valid approach to assess evaluative representation than direct measures. When directly and indirectly assessed attitudes dissociate, situational factors as well as the to-be-predicted behavior itself determine which outcome possesses greater behavioral relevance.
Somewhat relatedly, a retrieval explanation may account for the occasional finding of implicit US valence memory in the absence of explicit memory that is obtained in the PD procedure (i.e., when the implicit-memory parameter differs from zero;
Another important dissociation between different measures that can be explained by the specific properties of these measures is the dissociation between evaluation and expectancy, as reflected in the resistance-to-extinction phenomenon (e.g.,
To conclude this section, while we have illustrated that different dependent measures may have different properties, it is beyond the scope of the present account to make a-priori assumptions about the properties of a representative range of measures. When those properties were relevant to our account of a phenomenon, we have sought support by building on independent evidence (e.g.,
In this section, we address dissociation findings that can arise from factors involving multiple stages (e.g., from interactions between effects operating at different stages). In particular, we discuss the distinction between on-line and memory-based information integration. We also address the role of relational qualifiers and discuss recent findings regarding the (un-)controllability of EC.
An important issue when making memory-based judgments or decisions concerns the processes that integrate mnemonic contents to make these judgments or decisions. The strategies used for integration will depend on properties of the task, for instance, the available resources as well as the instructions during learning, but also participants’ expectations about how the learned information will be relevant for later parts of the study (i.e., the type of dependent measure they foresee). Here, we briefly sketch an important distinction relevant for information integration: online versus memory-based judgments (
First, it is well-known that on-line judgment or impression-formation tasks may lead to different outcomes than deferred judgment tasks that produce their judgments only later on the basis of retrieval from memory (
By contrast, in on-line tasks, learning instructions require participants to make use of the presented information to form a judgment about a target. In these tasks, judgments are assumed to be formed on-line and stored in memory in a summary fashion. When later asked to evaluate the target, the stored summary judgment can be retrieved without requiring further integration. In contrast to memory-based judgments, these on-line judgments are less strongly correlated with the information that can be retrieved from memory at the time of judgment, because here the summary judgment has already been formed during learning, such that later forgetting affects the retrieved information but not the summary judgment. In EC tasks, instructions take a wide variety of forms that vary along the online- versus memory-based dimension, with explicit impression formation requirements calling for on-line judgments, whereas passive viewing instructions allow participants to select their own encoding strategy, and memorization instructions call for a deferred memory-based judgment. We predict that the relation between memory and evaluative judgment will depend on the degree to which processing occurs in an on-line versus memory-based fashion.
A related but different distinction in memory research is that between prospective versus retrospective integration (
Dissociations may arise when the type of information integration interacts with properties of dependent measures. The distinction between on-line and memory-based decisions is relevant for the finding that indirect evaluative measures were sensitive to relational information only under impression-formation but not memorization goals (
Any information about the relation between CS and US is itself a stimulus and therefore part of the episode. For relational qualifiers to affect EC requires their successful encoding, maintenance, and retrieval, and thus depends on attentional resources and processing goals during encoding, on maintenance during the retention interval, and on retrieval and integration as just discussed. Relational information may be integrated with other stimulus information during encoding (e.g., depending on memorization vs. impression-formation goals) or may remain nonintegrated (e.g., if it is presented as an indirect cue). These factors will influence the effect of qualifiers on EC.
Recent studies have claimed that EC may be uncontrollable (
Instead we suggest a simple encoding-based explanation of control failure: The encoding task is clearly easier on affirmative than on negated trials because the latter likely require some form of additional processing, the effectiveness of which will depend on participants’ strategies for implementing the control instructions (e.g., negation of US valence, imagination of a stimulus of opposite valence) and motivation. If we assume that, therefore, participants fail to perform the required relational qualification process on a subset of to-be-negated trials, this would result in an EC effect in line with—rather than in opposition to—US valence. Such a residual unqualified EC effect was found and interpreted as evidence for uncontrollable EC (
The maintenance stage is a second possible locus at which the finding of partially uncontrolled EC may come about under memorization instructions: Let us assume that participants have perfectly encoded both the CS-US pair and the qualifying information. During the retention interval, parts of this information is likely to be forgotten or degraded (with different forgetting rates applying to specific perceptual detail versus abstract gist summaries). If the qualifier is forgotten, participants will later fail to invert their CS impression as instructed, yielding an “uncontrolled-EC” pattern for these CSs (e.g.,
Effects at retrieval may also be involved here and affect the degree to which control modifiers affect the evaluative outcomes: When participants use an analytic strategy during the evaluative task, they may take into account different subsets of the available information than under a non-analytic strategy (
In sum, there are several possible accounts for control-failure patterns that need to be compared empirically in future research. This task may be further complicated if different accounts apply under different conditions.
This section briefly addresses several additional questions relevant for this special issue.
Generally speaking, as a judgment based on episodic memory, EC should be subject to moderation by all those factors that moderate episodic memory and simple judgments based on its contents. Similarly, any interindividual differences that affect memory should also affect EC, for instance (but not limited to), the ability to consciously perceive brief and masked stimuli; working memory capacity; and fidelity of episodic long-term memory. With regard to the MINERVA 2 implementation, the following factors should moderate EC, beyond those already discussed above: the rate at which information is learned (moderated by, e.g., stimulus complexity, presentation duration, attention, load, and goals), the relative weight of attention given to the relevant different parts of the episode (e.g., CS, US, and qualifying information), the number of repetitions of each (type of) episode, and the rate at which information is forgotten.
Critically, MINERVA 2 predicts that similarities between encoded episodes (e.g., CS, US, and context) affect EC. A fundamental assumption of the MINERVA 2 model is its similarity-based retrieval mechanism: Past episodes in memory contribute more strongly to the retrieved information if they are similar to the retrieval cue than when they are dissimilar. If CSs are highly similar, their memory traces will be difficult to distinguish, and memory traces from different CSs may be confused with each other. As a consequence, EC effects should be easier to obtain when the CSs paired with positive and negative USs are dissimilar than when they are similar (see also the Prediction section below). As previously discussed, retrieval cues may encompass the CS presented by the experimenter but also external and internal context features. Hence, the model also predicts that the similarity between contexts during encoding and retrieval moderates the EC effect (
On the one hand, verbal instructional information may simply be construed as a stimulus that is encoded into memory and may affect CS evaluations. Future research will show whether and when it is integrated with co-occurrence information, and whether this depends on or dissociates as a function of the dependent measure. For instance, the symbolic and discrete nature of such verbal instructions may promote their use in informing direct evaluative responses. In contrast, it may be more difficult and time-consuming to compute CS evaluations via retrieval of weak and diffuse traces of CS-US co-occurrences.
On the other hand, the effects of instructions, and of verbal information in general, are somewhat beyond the scope of the present account. As we explained in the introduction (and discuss below), beyond rather simple effects of verbal information that are a by-product of memory processes, the present perspective is silent about effects of instructions that involve propositional reasoning processes.
The memory-based-judgment view naturally accounts for the relation between EC and memory highlighted in current reviews, especially the finding that EC is strongly correlated with memory for pairings (
More importantly, the memory-based-judgment view provides an account of a set of findings, identified in a recent review (
• EC is found under incidental learning conditions (e.g., in surveillance studies)
• EC may occur with weak memory for US valence (e.g., in PD studies)
• EC measures may be differentially sensitive to relational information and partly uncontrollable (e.g., forgetting of details; integration failure)
We have illustrated here how these phenomena can be understood as resulting from evaluative summaries that are affected by the information provided in the learning phase via its encoding, maintenance, and retrieval from episodic memory.
The present view implies that it will not be possible to eliminate memory without also eliminating EC. Memory and EC are not independent and cannot be doubly dissociated. It may sometimes be possible to find residual EC even at a point of low attention, suboptimal presentation, incidental learning, and with only weak memory for the pairings. But importantly, departing from this point, every manipulation that strengthens memory will also strengthen EC; it will not be possible to affect one without affecting the other.
We have outlined how incidental EC phenomena can be explained by episodic memory principles and their interaction with properties of dependent measures. Highlighting the similarities between EC and memory has proven fruitful beyond this limited focus, as illustrated by the independent work of Gast and colleagues (
The range of phenomena being discussed under a functional definition of EC is broad, covering such diverse findings as EC via verbal instruction and via experienced pairing, obtained via incidental and intentional learning, with measures such as explicit and projective judgments as well as binary classification tasks, and susceptible to moderation via a wide range of factors from top-down beliefs and goals to bottom-up viewing duration. Unless complex reasoning processes are involved, we believe the underlying machinery of episodic memory is capable of accounting for EC across this entire range. It is to be expected however, that a single set of parameter settings will not work across the entire range, but that parts of the model will need to be adapted to the specific phenomenon under study. For instance, our work on extinction illustrates that adjustments need to be made for the choice of dependent measure: If participants by default rely on momentary, context-specific information for expectancy judgments but on integrative summaries for evaluative judgments, this of course needs to be reflected in the model if it is to account for the empirical findings.
The present view is relatively flexible because it allows for the entire range of factors that affect memory to also affect EC. Importantly, however, because the flexibility was put in place to account for a wide range of memory phenomena far beyond EC, and was not added in order to explain EC, it should not be held against the present theoretical perspective of EC. By explaining EC as following from established theory, without making any new assumptions, the present view is in fact maximally parsimonious when not only simplicity but also scope is considered (i.e., it has greater
The MINERVA 2 model is used here to serve as an illustration of how the principles of episodic memory can account for the EC phenomenon. It formalizes the underlying assumptions of our basic hypothesis, and it helps to derive predictions about EC effects in established as well as novel situations. While the MINERVA 2 model may seem a somewhat outdated choice given its introduction more than 30 years ago, it is in fact still being applied and developed in a variety of domains to account for memory-informed cognition and behavior, for example, in specific implicit learning paradigms such as artificial grammar learning (
So far, we have formally applied the MINERVA 2 model to counterconditioning and extinction of EC. As we extend the application of this formal approach, we expect that the MINERVA 2 model can help account for many (but perhaps not all) EC phenomena that are based on relatively simple forms of memory retrieval. Additional assumptions will be required to model EC in general, and certain specific EC phenomena in particular. This is especially true for dynamic processes during encoding and maintenance, as well as assumptions about how the information retrieved from memory is weighed and integrated to inform subsequent processing. As we said earlier, the MINERVA 2 model accounts for the information available in memory at the time of retrieval or performance, and how it is retrieved. However, by itself, the model does not account for subsequent processing, such as reasoning processes that operate on the retrieved information. We have outlined how the model can be extended by introducing additional assumptions about attention allocation and information integration during encoding that have been substantiated by independent memory research. Our approach however cannot (and does not aim to) explain how reasoning processes affect evaluative judgments and behaviors; it focuses on the underlying episodic memory processes.
A related limitation concerns the underspecification of how the retrieved contents of memory informs behavior. We acknowledge that the implementation of the link between retrieved information and behavior in our own work is so far very simplistic and probably requires elaboration. For tests of theory, it is therefore important to rely on well-studied dependent measures; yet, knowledge about the dependent measures used in EC research is often lacking. Ideally, paradigms with validated formal measurement models (e.g., signal detection or drift diffusion) would be available to provide a tight link between the theory’s prediction and the data.
Memory models explain how learning episodes are encoded and maintained, and sometimes address how they inform recognition judgments and recall performance. Yet, they are typically silent as to how the contents of memory inform other judgments and measures that require more complex information integration. Not all dependent measures tap the encoded information in the same way, and these differences are important for our understanding of empirical findings. In this vein, our perspective echoes the work by
In the absence of validated measurement models, dissociations between dependent measures may always reflect properties of the measures themselves rather than the learning processes. Hence, it is important to keep the dependent measures constant between conditions.
The present account, based on MINERVA 2, is a single-process global-matching memory model that, given a cue, produces a familiarity signal and an echo that can be used to inform a variety of judgments. In the original proposition, it was conceived of as a model of declarative long-term memory and used to informing recognition decisions as well as frequency judgments (
In recognition memory, as in EC, there is a debate between single- and dual-process models (
Such an argument would be unconvincing, however, because it overlooks the important confound of memory strength in dissociations between recollection and familiarity (
These reviews confirmed the notion that the remember-know distinction was not used by participants in a way that equates memory strength across both types of responses; instead, stronger memories were more likely classified as
Any predictions that can be derived from the memory literature in general, and from the MINERVA 2 model in particular, can be used to test the present view. In testing predictions, it is important to note that any dissociations may be due to differences in how the information in memory is mapped onto the specific evaluative response required by that measure. In addition, the exclusion of reasoning processes is critical for tests of the present model. The PAL posits that learning results from reasoning processes that operate on the basis of the contents of memory; this implies that we can investigate whether a given EC phenomenon can be explained by memory processes only to the degree that the influence of reasoning processes relation is controlled. Past studies have attempted to achieve this by implementing incidental learning conditions, by presenting complex and irregular stimulus sequences, and/or by occupying participants’ working memory with an irrelevant task. Bearing in mind these constraints, below we suggest a few specific predictions that can be used to test the present account.
First, from the observation that stimulus similarity is a central factor in the model, a novel prediction can be derived that may be described as an EC analogon of the false-memory effect: EC effects should be affected by CS similarity because similar CSs may activate each other’s memory episodes. In episodic memory, this influence of similarity leads to false-memory phenomena in which lures that are similar or related to studied items are mistakenly recognized more often than dissimilar lures. Applied to EC, a novel (unpaired) stimulus that is similar to a CS paired with positive (negative) USs should be evaluated more positively (negatively) than a novel stimulus similar to a CS paired with negative (positive) USs.
A second prediction is that, if two highly similar CSs are paired with opposite-valence USs, then EC effects should be reduced (when compared with dissimilar CSs) because, at retrieval, the CS (at least partly) cues and retrieves episodes of the opposite valence that influence its evaluation. On the other hand, EC should be increased for similar CSs paired with same-valence USs because the CS (partly) cues a larger number of episodes that concur with the valence of the associated US.
Third, MINERVA 2 more generally predicts that EC should show similarity-based generalization patterns. Note that such patterns may however be overruled if additional verbal reasoning processes are involved (i.e., rule learning). Several studies have reported evidence for a default similarity-based pattern of evaluations (
The above discussion of current memory theory highlights two additional predictions that can be derived from the single-process memory model:
First, nondeclarative learning effects (e.g.,
Second, it is assumed that memory strength is predicted to be the underlying factor that determines the type of mnemonic experience (recollective or not). Applied to EC, when memory strength is controlled, EC should no longer vary as a function of ‘remember’ versus ‘know’ experiences.
The present memory-based-judgment perspective of evaluative learning posits that the information extracted from each learning instance is stored in episodic memory for later use. By restricting the flexibility at the encoding stage, this perspective highlights the necessity to account for processes operating at the retrieval or performance stage to specify how this information is actually used to inform cognitions and behaviors. We have shown that retrieval processes may be responsible for (some of) the observed dissociations that are often attributed to the learning stage. Links between retrieved information and behavior are often underspecified; to fill this gap, future research should focus on expanding our knowledge about dependent measures to establishing measurement theories and models that can be used to derive and test more precise predictions.
Another connection that requires specification is that between memory and reasoning (or, more generally, higher-order cognition accounts). In this respect, the present restriction to EC phenomena that do not involve reasoning can be argued to lack precision as it does not delineate what should count as reasoning. The underlying models do not provide a clear distinction:
A tighter link between episodic memory and learning is being developed in other research areas as well. Instance-based accounts are discussed not only in associative as well as implicit learning (
The authors have no funding to report.
The authors have declared that no competing interests exist.
We thank Karoline Bading, Olivier Corneille, Julia Haaf, Tobias Heycke, and Jan De Houwer for many discussions about theories of EC.
Its limited scope (or universality) is therefore balanced by increased specificity (or precision; for a discussion, see Glöckner and Betsch (2011).
The notion of episodic binding is a fundamental theoretical tenet of current theories across domains (Baddeley, 2000; Gershman & Daw, 2017; Hommel, 2004; Ranganath, 2010; Schmidt, De Houwer, & Rothermund, 2016; Whittlesea & Dorken, 1993). The notion of internally generated contents of memory features most prominently in the source monitoring framework (M. K. Johnson, Hashtroudi, & Lindsay, 1993), which holds that recollective memories can be identified as reflecting true events by recognizing the spontaneous self-generated thoughts that accompanied the event. In addition, its reality-monitoring aspect focuses on (the difficulty of) distinguishing memories for true events from those for self-generated thoughts.
This allows for retrieval of stable summary evaluations (Fazio, 2007) as well as for contextualized evaluations created at the time of judgment (Schwarz, 2007).
An exhaustive list of such factors is not provided as they do not necessarily follow from the basic hypothesis and are not an integral part of the present account of EC. The strength of support for the relevance of a given factor depends on independent evidence provided by the memory literature.
This is supported, for instance, by research on source memory showing that retaining episodic contextual details was associated with ‘remember’ judgments which represent recollective experiences (Meiser, Sattler, & Weisser, 2008).
Indirect effects are however possible if the effects of nondeclarative learning become available to declarative knowledge, for example, if performance on a task improves unexpectedly, which may then induce conscious hypothesis testing to detect the causes of this improvement (Haider & Frensch, 2009).