Short- and long-term memory contributions to immediate serial recognition: Evidence from serial position effects

A long-standing body of research supports the existence of separable short- and long-term memory systems, relying on phonological and semantic codes, respectively. The aim of the current study was to measure the contribution of long-term knowledge to short-term memory performance by looking for evidence of phonologically and semantically coded storage within a short-term recognition task, among developmental samples. Each experimental trial presented 4-item lists. In Experiment 1 typically developing children aged 5 to 6 years old showed evidence of phonologically coded storage across all 4 serial positions, but evidence of semantically coded storage at Serial Positions 1 and 2. In a further experiment, a group of individuals with Down syndrome was investigated as a test case that might be expected to use semantic coding to support short-term storage, but these participants showed no evidence of semantically coded storage and evidenced phonologically coded storage only at Serial Position 4, suggesting that individuals with Down syndrome have a verbal short-term memory capacity of 1 item. Our results suggest that previous evidence of semantic effects on “short-term memory performance” does not reflect semantic coding in short-term memory itself, and provide an experimental method for researchers wishing to take a relatively pure measure of verbal short-term memory capacity, in cases where rehearsal is unlikely.     

Relations between vocabulary development and verbal short-term memory: The relative importance of short-term memory for serial order and item information

Although many studies have shown an association between verbal short-term memory (STM) and vocabulary development, the precise nature of this association is not yet clear. The current study reexamined this relation in 4- to 6-year-olds by designing verbal STM tasks that maximized memory for either item or serial order information. Although empirical data suggest that distinct STM processes determine item and serial order recall, these were generally confounded in previous developmental studies. We observed that item and order memory tasks were independently related to vocabulary development. Furthermore, vocabulary development was more strongly associated with STM for order information in 4- and 6-year-olds and with STM for item information in 5-year-olds. These data highlight the specificity of verbal STM for serial order and item information and suggest a causal association between order STM processes and vocabulary development, at least in 4- and 6-year-olds.     

Lexical learning in bilingual adults: the relative importance of short-term memory for serial order and phonological knowledge

Studies of monolingual speakers have shown a strong association between lexical learning and short-term memory (STM) capacity, especially STM for serial order information. At the same time, studies of bilingual speakers suggest that phonological knowledge is the main factor that drives lexical learning. This study tested these two hypotheses simultaneously in participants with variable levels of English-French bilingual proficiency. A word-nonword paired-associate learning task was administered, with nonwords obeying French phonotactic patterns. French phonological knowledge was estimated by a composite French proficiency score summarizing productive and receptive French vocabulary knowledge as well as quantitative and qualitative measures of French exposure. STM measures maximized retention of order information (serial order reconstruction) or retention of phonological item information (single nonword delayed repetition). The French proficiency score and the serial order STM measure independently predicted performance on the paired-associate learning task. These results highlight the conjoined role of phonological knowledge and serial order STM in lexical learning. Importantly, serial order STM remains a strong predictor of lexical learning, even for bilingual individuals who have broad phonological knowledge.     

Distinctiveness and serial position functions in implicit memory

Serial position functions, with their characteristic primacy and recency effects, are ubiquitous in episodic memory tasks, and have also been observed in tasks tapping semantic memory. However, only one experiment, [Raanaas, R. K., & Magnussen, S. (2006a). Serial position effects in implicit memory. European Journal of Cognitive Psychology, 18, 398–414. doi:10.1080/09541440500162065], has demonstrated primacy and recency effects in implicit memory using an indirect memory test. In Experiment 1, we replicate this finding and in Experiment 2, we confirm a prediction that holds only if the serial position function observed in Experiment 1 was a “real” serial position function. These results confirm the presence of serial position functions in implicit memory and also support a general prediction of the relative distinctiveness principle that serial position functions should obtain whenever a set of items are ordered along a relevant dimension.     

Single-probe serial position recall: Evidence of modularity for olfactory,visual, and auditory short-term memory

The present study examined and compared order memory for a list of sequentially presented odours, unfamiliar faces, and pure tones. Employing single-probe serial position recall and following a correction for a response bias, qualitatively different serial position functions were observed across stimuli. Participants demonstrated an ability to perform absolute order memory judgments for odours. Furthermore, odours produced an absence of serial position effects, unfamiliar faces produced both primacy and recency, and pure tones produced recency but not primacy. Such a finding is contrary to the proposal by Ward, Avons, and Melling (2005) that the serial position function is task, rather than modality, dependent. In contrast, the observed functions support a modular conceptualization of short-term memory (e.g., Andrade & Donaldson, 2007; Baddeley & Hitch, 1974), whereby separate modality-specific memorial systems operate. An alternative amodal interpretation is also discussed wherein serial position function disparities are accommodated via differences in the psychological distinctiveness of stimuli (Hay, Smyth, Hitch, & Horton, 2007).     

Serial position effects in 2-alternative forced choice recognition: Functional equivalence across visual and auditory modalities

Two experiments examined Ward, Avons, and Melling's (2005) proposition that the serial position function is task, rather than modality, dependent. Specifically, they proposed that for backward testing the 2-alternative forced-choice (2AFC) recognition paradigm is characterised by single-item recency irrespective of the modality of the stimulus presentation. In Experiment 1 the same nonword sequences, presented both visually or auditorily, produced qualitatively equivalent serial position functions with 2AFC testing. Forward testing produced a flat serial position function, while backward testing produced two-item recency in the absence of primacy. In order to rule out the possibility that the serial position functions for visual stimuli were the product of sub-vocal rehearsal, Experiment 2 employed articulatory suppression during the presentation phase. Serial position function equivalence was again observed together with a modest impairment in overall recognition rates. Taken together, these data are consistent with the Ward et al. proposition and further support the existence of a visual memory that can facilitate storage of visual-verbal material (e.g. Logie, Della Sella, Wynn, & Baddeley, 2000). However, the observation of two-item recency contradicts the original duplex account of single-item recency traditionally observed for backwards recognition testing of visual stimuli (Phillips & Christie, 1977).     

Short-term memory for serial order supports vocabulary development: New evidence from a novel word learning paradigm

Although recent studies suggest a strong association between short-term memory (STM) for serial order and lexical development, the precise mechanisms linking the two domains remain to be determined. This study explored the nature of these mechanisms via a microanalysis of performance on serial order STM and novel word learning tasks. In the experiment, 6- and 7-year-old children were administered tasks maximizing STM for either item or serial order information as well as paired-associate learning tasks involving the learning of novel words, visual symbols, or familiar word pair associations. Learning abilities for novel words were specifically predicted by serial order STM abilities. A measure estimating the precision of serial order coding predicted the rate of correct repetitions and the rate of phoneme migration errors during the novel word learning process. In line with recent theoretical accounts, these results suggest that serial order STM supports vocabulary development via ordered and detailed reactivation of the novel phonological sequences that characterize new words.     

Additivity of semantic and phonological effects: Evidence from speech production in Mandarin

A number of previous studies using picture–word interference (PWI) tasks conducted with speakers of Western languages have demonstrated non-additive effects of semantic and form overlap between pictures and words, which may indicate underlying non-discrete processing stages in lexical retrieval. The present study used Mandarin speakers and presented Chinese characters as distractors. In two experiments, we crossed semantic relatedness with “pure” phonological (i.e., orthographically unrelated) relatedness and found statistically additive effects. In a third experiment, semantic relatedness was crossed with orthographic overlap (phonological overlap was avoided), and once again we found an additive pattern. The results are discussed with regard to possible cross-linguistic differences between Western and non-Western languages in terms of phonological encoding, as well as concerning the locus of relatedness effects in PWI tasks.     

A calibration explanation of serial position effects in evaluative judgments

Judges often evaluate stimulus series on dimensions for which no physical scale exists; for example, when judging academic ability in oral examinations. We propose that judges deal with this problem by calibrating an internal judgment scale that maps stimulus input onto available judgment categories. This calibration process implies serial position effects: Judges should initially avoid extreme categories, because using extreme categories reduces judgmental degrees of freedom, thereby increasing the possibility of internal consistency violations. In four experiments, we show that judgments become indeed more extreme later in a series of judgments. Judges evaluated the same good (poor) performances more positive (negative) at the end of a sequence compared to the beginning. Judges’ expertise did not prevent the effect, but allowing end-of-sequence judgments reduced serial position effects. We discuss the implications and possible remedies of these calibration effects on judgment extremity.     

Neighbourhood effects on error rates in speech production

Models of speech production differ on whether phonological neighbourhoods should affect processing, and on whether effects should be facilitatory or inhibitory. Inhibitory effects of large neighbourhoods have been argued to underlie apparent anti-frequency effects, whereby high-frequency default features are more prone to mispronunciation errors than low-frequency nondefault features. Data from the original SLIPs experiments that found apparent anti-frequency effects are analysed for neighbourhood effects. Effects are facilitatory: errors are significantly less likely for words with large numbers of neighbours that share the characteristic that is being primed for error ("friends"). Words in the neighbourhood that do not share the target characteristic ("enemies") have little effect on error rates. Neighbourhood effects do not underlie the apparent anti-frequency effects. Implications for models of speech production are discussed.     

The relationship between language production and verbal short-term memory: The role of stress grouping

This study investigates the influence of stress grouping on verbal short-term memory (STM). English speakers show a preference to combine syllables into trochaic groups, both lexically and in continuous speech. In two serial recall experiments, auditory lists of nonsense syllables were presented with either trochaic (STRONG–weak) or iambic (weak–STRONG) stress patterns, or in monotone. The acoustic correlates that carry stress were also manipulated in order to examine the relationship between input and output processes during recall. In Experiment 1, stressed and unstressed syllables differed in intensity and pitch but were matched for spoken duration. Significantly more syllables were recalled in the trochaic stress pattern condition than in the iambic and monotone conditions, which did not differ. In Experiment 2, spoken duration and pitch were manipulated but intensity was held constant. No effects of stress grouping were observed, suggesting that intensity is a critical acoustic factor for trochaic grouping. Acoustic analyses demonstrated that speech output was not identical to the auditory input, but that participants generated correct stress patterns by manipulating acoustic correlates in the same way in both experiments. These data challenge the idea of a language-independent STM store and support the notion of separable phonological input and output processes.     

Working memory deficits in developmental dyscalculia: The importance of serial order

Although a number of studies suggests a link between working memory (WM) storage capacity of short-term memory and calculation abilities, the nature of verbal WM deficits in children with developmental dyscalculia (DD) remains poorly understood. We explored verbal WM capacity in DD by focusing on the distinction between memory for item information (the items to be retained) and memory for order information (the order of the items within a list). We hypothesized that WM for order could be specifically related to impaired numerical abilities given that recent studies suggest close interactions between the representation of order information in WM and ordinal numerical processing. We investigated item and order WM abilities as well as basic numerical processing abilities in 16 children with DD (age: 8–11 years) and 16 typically developing children matched on age, IQ, and reading abilities. The DD group performed significantly poorer than controls in the order WM condition but not in the item WM condition. In addition, the DD group performed significantly slower than the control group on a numerical order judgment task. The present results show significantly reduced serial order WM abilities in DD coupled with less efficient numerical ordinal processing abilities, reflecting more general difficulties in explicit processing of ordinal information.     

Serial position effects in visual short-term memory for words and abstract spatial patterns

Two experiments tested the effects of list postion, and retention-interval in recognition for two distinct stimulus categories in young adults. Stimulus categories were spatial abstract patterns and words presented on a computer screen. At short delay intervals recency effects predominates and at longer delay intervals a primacy effect predominates in both experiments, indicating similar basic memory processes producing the serial position functions for the two different categories of visual stimuli, but as length of retention-interval increases, memory for first list items improves for words and remains constant for abstract patterns. Recency functions are similar for both stimulus categories tested.     

Dissociation of short- and long-term face memory: evidence from long-term recency effects in temporal lobe epilepsy

We tested whether memory deficits in temporal lobe epilepsy (TLE) are better described by a single- or dual-store memory model. To this aim, we analyzed the influence of TLE and proactive interference (PI) on immediate and 24-h long-term recency effects during face recognition in 16 healthy participants and 18 right and 21 left non-surgical TLE patients. PI in healthy participants or TLE erased the long-term recency effect, but left the immediate recency effect unaffected. Although the immediate recency effect was still visible in right TLE patients, the number of detected recency items during immediate recognition was decreased in right TLE compared to left TLE. Right TLE was also related to decreased detection of pre-recency items during delayed recognition compared to left TLE, and decreased detection of pre-recency items during immediate recognition under PI. The results show that the temporal lobes are necessary for the long-term recency effect, but not for the immediate recency effect, and thus speak for a dissociation of short- and long-term memory for faces. Right TLE is related to more severe long-term memory deficits than left TLE and is also related to additional short-term memory deficits for faces.     

Eyewitness identification in simultaneous and sequential lineups: an investigation of position effects using receiver operating characteristics

For decades, sequential lineups have been considered superior to simultaneous lineups in the context of eyewitness identification. However, most of the research leading to this conclusion was based on the analysis of diagnosticity ratios that do not control for the respondent’s response criterion. Recent research based on the analysis of ROC curves has found either equal discriminability for sequential and simultaneous lineups, or higher discriminability for simultaneous lineups. Some evidence for potential position effects and for criterion shifts in sequential lineups has also been reported. Using ROC curve analysis, we investigated the effects of the suspect’s position on discriminability and response criteria in both simultaneous and sequential lineups. We found that sequential lineups suffered from an unwanted position effect. Respondents employed a strict criterion for the earliest lineup positions, and shifted to a more liberal criterion for later positions. No position effects and no criterion shifts were observed in simultaneous lineups. This result suggests that sequential lineups are not superior to simultaneous lineups, and may give rise to unwanted position effects that have to be considered when conducting police lineups.     

Practice effects on speech production planning: evidence from slips of the tongue in spontaneous vs. preplanned speech in Japanese

The present study addresses the question of how practice in expressing the content to be conveyed in a specific situation influences speech production planning processes. A comparison of slips of the tongue in Japanese collected from spontaneous everyday conversation and those collected from largely preplanned conversation in live-broadcast TV programs reveals that, although there are those aspects of speech production planning that are unaffected by practice, there are various practice effects, most of which can be explained in terms of automatization of the processing of content, resulting in shifts in the loci of errors.     

工作记忆中的积极效应：情绪效价与任务相关性的影响

积极效应指相比于年轻人, 老年人更倾向于优先加工积极情绪刺激而非消极情绪刺激。近年来工作记忆的研究发现积极效应会受到情绪效价与任务相关性的影响：情绪效价作为任务相关属性的研究支持工作记忆中存在积极效应, 具体表现为老年人对积极情绪刺激记忆的增强, 以及对消极情绪刺激记忆的减弱; 情绪效价作为工作记忆任务无关属性的研究相对较少, 且未发现一致的积极效应, 提示情绪效价及任务相关性均为影响工作记忆积极效应的关键因素。脑成像的研究初步表明, 工作记忆中情绪加工上的年龄效应与背侧执行系统和腹侧情绪系统的随龄功能变化有关。社会情绪选择理论与双竞争模型对工作记忆中的积极效应具备较大的解释力, 而动态整合理论尚缺乏实证研究支持。未来研究可进一步探究老年人工作记忆不同阶段情绪加工的特点, 澄清不同情绪材料内在编码过程上的差异对积极效应发生机制的潜在影响, 探讨情绪效价及任务相关性影响工作记忆积极效应的关键神经环路, 并揭示情绪工作记忆训练提升老年人认知功能与情绪体验的内在机制及其潜在应用价值。     

Tic Tac Toe: effects of predictability and importance on acoustic prominence in language production

Importance and predictability each have been argued to contribute to acoustic prominence. To investigate whether these factors are independent or two aspects of the same phenomenon, na?ve participants played a verbal variant of Tic Tac Toe. Both importance and predictability contributed independently to the acoustic prominence of a word, but in different ways. Predictable game moves were shorter in duration and had less pitch excursion than less predictable game moves, whereas intensity was higher for important game moves. These data also suggest that acoustic prominence is affected by both speaker-centered processes (speaker effort) and listener-centered processes (intent to signal important information to the listener).