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Visual-verbal serial recall is disrupted when task-irrelevant background speech has to be ignored. Contrary to previous suggestion, it has recently been shown that the magnitude of disruption may be accentuated by the semantic properties of the irrelevant speech. Sentences ending with unexpected words that did not match the preceding semantic context were more disruptive than sentences ending with expected words. This particular instantiation of a deviation effect has been termed the semantic mismatch effect. To establish a new phenomenon, it is necessary to show that the effect can be independently replicated and does not depend on specific boundary conditions such as the language of the stimulus material. Here we report a preregistered replication of the semantic mismatch effect in which we examined the effect of unexpected words in 4 different languages (English, French, German, and Swedish) across 4 different laboratories. Participants performed a serial recall task while ignoring sentences with expected or unexpected words that were recorded using text-to-speech software. Independent of language, sentences ending with unexpected words were more disruptive than sentences ending with expected words. In line with previous results, there was no evidence of habituation of the semantic mismatch effect in the form of a decrease in disruption with repeated exposure to the occurrence of unexpected words. The successful replication and extension of the effect to different languages indicates the expression of a general and robust mechanism that reacts to violations of expectancies based on the semantic content of the irrelevant speech.

In the cocktail party phenomenon, participants cannot attend to more than 1 stream of information, but sometimes detect their own name being presented in the irrelevant message during a selective listening task. Here we present a preregistered replication of the phenomenon, in which we also tested whether semantically unexpected words have a similar effect and whether individual differences in working memory capacity as measured by the operation and running-span tasks are related to the ability to detect one's own name or unexpected words in the irrelevant message. Twenty-nine percent of the participants reported noticing their own name, and those who did made more errors on relevant, to-be-shadowed words presented around the time of the name. Low-span participants were more likely than high-span participants to notice their names and to commit shadowing errors concurrently to the presentation of the name or shortly after. In contrast, semantically unexpected words were rarely detected, nor were they associated with shadowing errors in the relevant message. Our results demonstrate once again that highly relevant stimuli such as one's own name are capable of attracting and capturing attention for a short period of time. Our results also demonstrate that unexpected words within sentences do not belong to this category of stimuli.

A large body of evidence shows an animacy effect on memory in that animate entities are better remembered than inanimate ones. Yet, the reason for this mnemonic prioritization remains unclear. In the survival processing literature, the assumption that richness of encoding is responsible for adaptive memory benefits has received substantial empirical support. In the present study, we examined whether richness of encoding may be considered as a possible mechanism underlying the animacy effect as well. Specifically, we tested a prediction derived from the assumption that processing animate words results in a richer set of associations to other items in memory than processing inanimate words, which may provide participants with a larger set of retrieval cues at test. In Experiments 1 and 3 the animacy effect was replicated in an intentional learning paradigm with different sets of to-be-remembered animate and inanimate words. In Experiments 2 and 4, participants were asked to report any ideas coming to mind in response to these words at encoding. Participants were also asked to recall the words in a surprise recall test. The results showed a reliable animacy effect on free recall in all four experiments, that is, independently of whether encoding was intentional or incidental. Most importantly, the results of Experiments 2 and 4 show that participants spontaneously generated more ideas in response to animate words than in response to inanimate words. The findings suggest that richness of encoding should be further considered as a potential proximate mechanism of the animacy effect.

Sequences of auditory objects such as one-syllable words or brief sounds disrupt serial recall of visually presented targets even when the auditory objects are completely irrelevant for the task at hand. The "token set size effect" is a label for the claim that disruption increases only when moving from a 1-token distractor sequence (e.g., "AAAAAAAA") to a token set size of 2 (e.g., "ABABABAB") but remains constant when moving from a token set size of 2 to a larger token set size (e.g., "ABCABCAB" or "DAGCFBEH"). Here we show that this claim was incorrect and based on experiments with insufficient statistical power. With sufficient statistical power it can be shown that disruption increases not only when the distractor token set size increases from 1 to 2, but also when it increases from two to eight one-syllable words (Experiment 1) and brief instrumental sounds (Experiment 2). These findings have implications for theories of auditory distraction which differ in their predictions about whether the distractor-induced performance decrement should (a) only be determined by acoustic differences between immediately adjacent distractor tokens (duplex-mechanism account) or (b) gradually increase as a function of the variability in the distractor set (attentional account). The present data are inconsistent with the duplex-mechanism account and support the attentional account.

Short-term memory (STM) for serially presented visual items is disrupted by task-irrelevant, to-beignored speech. Five experiments investigated the extent to which irrelevant speech is processed semantically by contrasting the following two hypotheses: (1) semantic processing of irrelevant speech is limited and does not interfere with serial STM or (2) irrelevant speech is routinely processed semantically at an interlexical level to allow for the detection of stimuli that are of potential relevance for the individual. We tested these hypotheses by comparing the disruption of serial recall by distractor sentences with semantically expected endings to that of sentences with semantically unexpected endings. Sentences with unexpected endings consistently produced more disruption than sentences with expected endings. Phonologically expected, but semantically unexpected endings had the same effect, demonstrating that a semantic and not a phonological mismatch is responsible for the increased disruption. In all five experiments, the semantic mismatch effect was not reduced after repeated exposure to sentences with unexpected endings. The results suggest that (1) semantic processing occurs at the interlexical level of irrelevant speech, which requires the integration of words into the sentence context and (2) the semantic content of a distractor interferes with the maintenance of serial information in short-termmemory if it is unexpected.

Rating the relevance of words for the imagined situation of being stranded in the grasslands without survival material leads to exceptionally good memory for these words. This survival processing effect has received much attention because it promises to elucidate the evolutionary foundations of memory. However, the proximate mechanisms of the survival processing effect have to be identified before informed speculations about its adaptive function are possible. Here, we test and contrast 2 promising accounts of the survival processing effect. According to the 1st account, the effect is the consequence of the prioritized processing of threat-related information. According to the 2nd account, thinking about the relevance of items for survival stimulates thinking about object function, which is a particularly elaborate form of encoding. Experiment 1 showed that the emotional properties of the survival scenario, as manipulated by the negative or positive framing of the scenario, did not influence recall. A focus on threat at encoding led to worse recall than a focus on function. The latter finding was replicated in Experiment 2, which further showed that focusing on threat did not lead to a memory advantage over a pleasantness control condition. The beneficial effect of inducing a functional focus at encoding even surpasses that of the standard survival processing instruction. Together, the results support the theory that thinking about function is an important component of the survival processing effect.

Memory for words rated according to their relevance in a grassland survival context is exceptionally good. According to Nairne, Thompson, and Pandeirada's (2007) evolutionary-based explanation, natural selection processes have tuned the human memory system to prioritize the processing of fitness-relevant information. The survival-processing memory advantage has been replicated numerous times, but very little is known about the proximate mechanisms behind it. The richness-of-encoding hypothesis (Kroneisen & Erdfelder, 2011) implies that rating the usefulness of items in a survival context leads to the generation of a large number of ideas that may be used as retrieval cues at test to boost recall. In Experiment 1, the typical survival-processing recall advantage was obtained when words were rated according to their usefulness in 1 of 3 fictional contexts. In Experiment 2, participants were asked to write down any ideas that came to mind when thinking about the usefulness of the words. Consistent with the richness-of-encoding hypothesis, participants generated more ideas in the survival condition than in the fitness-irrelevant control conditions. In Experiment 3, participants generated more ideas for congruent than for incongruent words, demonstrating that the richness-of-encoding hypothesis can also account for the previously obtained congruency effect on recall (Butler, Kang, & Roediger, 2009). In both experiments the number of ideas written down predicted future recall performance well. Our results provide further evidence for the assumption that richness of encoding is an important proximate mechanism involved in memory performance in the survival-processing paradigm.