Dennis Norris

MRC Cognition and Brain Sciences Unit | MRC

Gathercole et al. (Journal of Memory and Language, 105, 19-42, 2019) presented a cognitive routine framework for explaining the underlying mechanisms of working memory (WM) training and transfer. This framework conceptualizes training-induced changes as the acquisition of novel cognitive routines similar to learning a new skill. We further infer th...

Recent masked priming studies investigating the recognition of letters with diacritics with native readers of the script have consistently yielded an asymmetric pattern of priming such that a base-letter prime without the diacritic speeds up the recognition of the letter with a diacritic almost as much as an identity prime, but not vice versa (e.g....

We contrast two computational models of sequence learning. The associative learner posits that learning proceeds by strengthening existing association weights. Alternatively, recoding posits that learning creates new and more efficient representations of the learned sequences. Importantly, both models propose that humans act as optimal learners but...

Models of visual word recognition share the assumption that lexical access is based on abstract letter identities. The present study re-examined the assumption that this is because information about the visual form of the letter is lost early in the course of activating the abstract letter identities. The main support for this assumption has come f...

Short-term verbal memory is improved when words can be chunked into larger units. Miller (1956) suggested that the capacity of verbal short-term memory is determined by the number of chunks that can be stored in memory, rather than by the number of items or the amount of information. But how does the improvement due to chunking come about, and is m...

Science regularly experiences periods in which simply describing the world is prioritised over attempting to explain it. Cognition, this journal, came into being some 45 years ago as an attempt to lay one such period to rest; without doubt, it has helped create the current cognitive science climate in which theory is decidedly welcome. Here we summ...

Are letters with a diacritic (e.g., â) recognized as a variant of the base letter (e.g., a), or as a separate letter identity? Two recent masked priming studies, one in French and one in Spanish, investigated this question, concluding that this depends on the language-specific linguistic function served by the diacritic. Experiment 1 tested this li...

Running span can be performed by either passively listening to memory items or actively updating the target set. Previous research suggests that the active updating process is demanding and time consuming and is favored at slow rates of presentation while the passive strategy is employed at fast rates. Two experiments examined the time course of re...

Memory for verbal material improves when words form familiar chunks. But how does the improvement due to chunking come about? Two possible explanations are that the input might be actively recoded into chunks, each of which takes up less memory capacity than items not forming part of a chunk (a form of data compression), or that chunking is based o...

The negative priming effect is an increase in interference when the response to the target on the current trial corresponds to the response to the distractor word on a preceding trial. Contrary to the commonly held belief that the negative priming effect is ubiquitous in the Stroop task, in the original study by Neill (1977), negative priming was f...

In Norris (2017), I explained why the notion of activated LTM (long-term memory) combined with a focus of attention was unable to perform the computations required to support short-term memory (STM) and argued that those extra computations must require a separate STM system. Cowan (2019) made the alternative proposal that this full set of computati...

Reading is resilient to distortion of letter order within a word. This is evidenced in the "transposed-letter (TL) priming effect," the finding that a prime generated by transposing adjacent letters in a word (e.g., jugde) facilitates recognition of the base word (e.g., JUDGE), more than a "substituted-letter" control prime in which the transposed...

Is the capacity of short-term memory fixed, or does it improve with practice? It is already known that training on complex working memory tasks is more likely to transfer to untrained tasks with similar properties, but this approach has not been extended to the more basic short-term memory system responsible for verbal serial recall. Here we invest...

Following Conrad (1965, Journal of Verbal Learning and Verbal Behavior, 4, 161–169) it is often assumed that backward verbal serial recall is performed by repeated forward scans through the list and then recalling the last remaining item. Direct evidence for this peel-off strategy is relatively weak, and there has to date been no examination of its...

Running span can be performed by either passively listening to to-be-remembered items or actively updating the target set during presentation. This choice of strategy is influenced by the rate of presentation in the task. Previous research suggests that the active updating process is demanding and time-consuming. It is favored at relatively slow ra...

We present a new framework characterizing training-induced changes in WM as the acquisition of novel cog-nitive routines akin to learning a new skill. Predictions were tested in three studies analyzing the transfer between WM tasks following WM training. Study 1 reports a meta-analysis establishing substantial transfer when trained and untrained ta...

We contrast two accounts of how novel sequences are learned. The first is that learning changes the signal-to-noise ratio (SNR) of existing neural representations by reducing noise or increasing signal gain. Alternatively, learning might cause the initial representation of the sequence to be recoded into more efficient representations such as chunk...

The data presented in this article are produced as part of the original research article entitled “Working memory training involves learning new skills” (Gathercole, Dunning, Holmes & Norris, in press). This article presents a dataset of coded features for pairs of trained and untrained working memory (WM) tasks from randomized controlled trials of...

Masked priming tasks have been used widely to study early orthographic processes—the coding of letter position and letter identity. Recently, using masked priming in the same–different task Lupker, Nakayama, and Perea (2015a) reported finding a phonological priming effect with primes presented in Japanese Katakana, and English target words presente...

We report an experiment in which we varied the nature of the articulatory suppression task being performed during a filled retention interval in serial recall. During the retention interval participants performed one of three computer-paced colour naming tasks designed to prevent subvocal rehearsal: A Stroop color-interference task with items prese...

Humans have an almost unbounded ability to adapt their behaviour to perform different tasks. In the laboratory, this flexibility is sometimes viewed as a nuisance factor that prevents access to the underlying cognitive mechanisms of interest. For example, in order to study “automatic” lexical processing, psycholinguists have used masked priming or...

Human bias towards more recent events is a common and well-studied phenomenon. Recent studies in visual perception have shown that this recency bias persists even when past events contain no information about the future. Reasons for this suboptimal behavior are not well understood and the internal model that leads people to exhibit recency bias is...

Human bias towards more recent events is a common and well-studied phenomenon. Recent studies in visual perception have shown that this recency bias persists even when past events contain no information about the future. Reasons for this suboptimal behaviour are not well understood and the internal model that leads people to exhibit recency bias is...

The question of whether overt recall of to-be-remembered material accelerates learning is important in a wide range of real-world learning settings. In the case of verbal sequence learning, previous research has proposed that recall either is necessary for verbal sequence learning (Cohen & Johansson Journal of Verbal Learning and Verbal Behavior, 6...

Short-term verbal memory is improved when words in the input can be chunked into larger units. Miller (1956) suggested that the capacity of verbal short-term memory is determined by the number of chunks that can be stored in memory, and not by the number of items or the amount of information. But how does the improvement due to chunking come about?...

Running span is generally considered a working memory updating task, yet the mechanisms underlying task execution remain unspecified. We employ a novel paradigm to investigate the time-course of cognitive demand posited to indicate an updating process (Experiment 1) and the impact of varying the rate of stimulus presentation (Experiment 2).

Using the oral and manual Stroop tasks we tested the claim that retrieval of meaning from a written word is automatic, in the sense that it cannot be controlled. The semantic interference effect (greater interference caused by color-related words than color-neutral words) was used as the index of semantic activation. To manipulate the level of atte...

Page and Norris [(2008). Is there a common mechanism underlying word-form learning and the Hebb repetition effect? Experimental data and a modelling framework. In A. Thorn & M. P. A. Page (Eds.), Interactions between short-term and long-term memory in the verbal domain; (2009). A model linking immediate serial recall, the Hebb repetition effect and...

A commonly expressed view is that short-term memory (STM) is nothing more than activated long-term memory. If true, this would overturn a central tenet of cognitive psychology—the idea that there are functionally and neurobiologically distinct short- and long-term stores. Here I present an updated case for a separation between short- and long-term...

Neural mechanisms which bind items into sequences have been investigated in a large body of research in animal neurophysiology and human neuroimaging. However, a major problem in interpreting this data arises from a fact that several unrelated processes, such as memory load, sensory adaptation, and reward expectation, also change in a consistent ma...

Memory for verbal material improves when words form familiar chunks. But how does theimprovement due to chunking come about? Two possible explanations are that the inputmight be actively recoded into chunks, each of which takes up less memory capacity thanitems not forming part of a chunk (a form of data compression), or that chunking is basedon re...

Humans have an almost unbounded ability to adapt their behaviour to perform different tasks. In the laboratory, this flexibility is sometimes viewed as a nuisance factor that prevents access to the underlying cognitive mechanisms of interest. For example, in order to study “automatic” lexical processing, psycholinguists have used masked priming or...

Page and Norris [(2008). Is there a common mechanism underlying word-form learning and the Hebb repetition effect? Experimental data and a modelling framework. In A. Thorn & M. P. A. Page (Eds.), Interactions between short-term and long-term memory in the verbal domain; (2009). A model linking immediate serial recall, the Hebb repetition effect and...

We report data from an experiment in which participants performed immediate serial recall of visually presented words with or without articulatory suppression, while also performing homophone or rhyme detection. The separation between homophonous or rhyming pairs in the list was varied. According to the working memory model (Baddeley, 1986; Baddele...

We report data from an experiment where participants performed immediate serial recall of visually presented words with or without articulatory suppression while also performing homophone or rhyme detection. The separation between homophonous or rhyming pairs in the list was varied. According to the Working Memory model (Baddeley & Hitch, 1974; Bad...

Supplementary material

Many complex tasks require people to bind individual events into a sequence that can be held in short term memory (STM). For this purpose information about the order of the individual events in the sequence needs to be maintained in an active and accessible form in STM over a period of few seconds. Here we investigated how the temporal order inform...

A commonly expressed view is that short-term memory (STM) is nothing more than activated long-term memory. If true, this would overturn a central tenet of cognitive psychology-the idea that there are functionally and neurobiologically distinct short- and long-term stores. Here I present an updated case for a separation between short- and long-term...

Neural mechanisms which bind items into sequences have been investigated in a large body of research in animal neurophysiology and human neuroimaging. However, a major problem in interpreting this data arises from a fact that several unrelated processes, such as memory load, sensory adaptation, and reward expectation, also change in a consistent ma...

Many complex tasks require people to bind individual events into a sequence that can be held in short term memory (STM). For this purpose information about the order of the individual events in the sequence needs to be maintained in an active and accessible form in STM over a period of few seconds. Here we investigated how the temporal order inform...

We report distributional analyses of response times (RT) in two variants of the color-word Stroop task using manual keypress responses. In the classic Stroop task, in which the color and word dimensions are integrated into a single stimulus, the Stroop congruence effect increased across the quantiles. In contrast, in the primed Stroop task, in whic...

Nonwords created by transposing two non-adjacent orthographic consonants (CONDISER) have been reported to produce more priming for their baseword (CONSIDER), and to be classified as a nonword less readily than nonwords created by transposing two orthographic vowels (CINSODER). We investigate the origin of this difference and its relevance for theor...

Nonwords created by transposing two non-adjacent orthographic consonants (CONDISER) have been reported to produce more priming for their baseword (CONSIDER), and to be classified as a nonword less readily than nonwords created by transposing two orthographic vowels (CINSODER). We investigate the origin of this difference and its relevance for theor...

Most complex tasks require people to bind individual stimuli into a sequence in short term memory (STM). For this purpose information about the order of the individual stimuli in the sequence needs to be in active and accessible form in STM over a period of few seconds. Here we investigated how the temporal order information is shared between the p...

Neural mechanisms which bind items into sequences have been investigated in a large body of research in animal neurophysiology and human neuroimaging. However, a major problem in interpreting this data arises from a fact that several unrelated processes, such as memory load, sensory adaptation, and reward expectation, also change in a consistent ma...

In 2 variants of the color-word Stroop task, we compared 5 types of color-neutral distractors-real words (e.g., ), pseudowords (e.g., ), consonant strings (e.g., ), symbol strings (e.g., #$%), and a row of Xs (e.g., )-as well as incongruent color words (e.g., displayed in red). When participants named the color, relative to a row of Xs, words and p...

This commentary on Gow and Olson [2015. Sentential influences on acoustic-phonetic processing: A Granger causality analysis of multimodal imaging data. Language, Cognition and Neuroscience. Advance online publication. doi:10.1080/23273798.2015.1029498] questions in three ways their conclusion that speech perception is based on interactive processin...

considers one aspect of the relation between connectionism and the traditional information-processing approach to cognitive psychology / it is often claimed that connectionism gives us a new language for describing psychological theories / Norris asks whether the new language simply gives us a way of describing and implementing the processes repres...

Not only can the pitfalls that Firestone & Scholl (F&S) identify be generalised across multiple studies within the field of visual perception, but also they have general application outside the field wherever perceptual and cognitive processing are compared. We call attention to the widespread susceptibility of research on the perception of speech...

We report three experiments in which participants performed written serial recall of visually presented verbal sequences with items varying in visual similarity. In Experiments 1 and 2 native speakers of Japanese recalled visually presented Japanese Kanji characters. In Experiment 3, native speakers of English recalled visually presented words. In...

A masked nonword prime generated by transposing adjacent inner letters in a word (e.g., jugde) facilitates the recognition of the target word (JUDGE) more than a prime in which the relevant letters are replaced by different letters (e.g., junpe). This transposed-letter (TL) priming effect has been widely interpreted as evidence that the coding of l...

Speech perception involves prediction, but how is that prediction implemented? In cognitive models prediction has often been taken to imply that there is feedback of activation from lexical to pre-lexical processes as implemented in interactive-activation models (IAMs). We show that simple activation feedback does not actually improve speech recogn...

The question of whether overt recall of to-be-remembered material accelerates learning is important in a wide range of real-world learning settings. In the case of verbal sequence learning, previous research has proposed that recall either is necessary for verbal sequence learning (Cohen & Johansson Journal of Verbal Learning and Verbal Behavior, 6...

In visual word recognition tasks, digit primes that are visually similar to letter string targets (e.g., 4/A, 8/B) are known to facilitate letter identification relative to visually dissimilar digits (e.g., 6/A, 7/B); in contrast, with letter primes, visual similarity effects have been elusive. In the present study we show that the visual similarit...

Here we investigate how order information is represented in auditory-verbal short-term memory (STM). We used fMRI and a serial recall task to dissociate neural activity patterns representing the phonological properties of the items stored in STM from the patterns representing their order. For this purpose, we analyzed fMRI activity patterns elicite...

We investigated the role of the visual similarity of masked primes to targets in a lexical decision experiment. In the primes, some letters in the target (e.g., A in ABANDON) had either visually similar letters (e.g., H), dissimilar letters (D), visually similar digits (4), or dissimilar digits (6) substituted for them. The similarities of the digi...

In four experiments using a variation of the Hebb repetition task, we investigated the effects on learning rate, of repetition spacing and of the overlap in experimental items between repeating and nonrepeating lists. In the first two experiments it was shown that when repeating and nonrepeating lists were all permutations of the same items, learni...

Reading is a complex process that draws on a remarkable number of diverse perceptual and cognitive processes. In this review, I provide an overview of computational models of reading, focussing on models of visual word recognition-how we recognise individual words. Early computational models had 'toy' lexicons, could simulate only a narrow range of...

Open bigram (OB) models (e.g., SERIOL: Whitney, 2001, 2008; Binary OB, Grainger & van Heuven, 2003; Overlap OB, Grainger et al., 2006; Local combination detector model, Dehaene et al., 2005) posit that letter order in a word is coded by a set of ordered letter pairs. We report three experiments using bigram primes in the same-different match task,...

Much of what we need to remember consists of sequences of stimuli, experiences, or events. Repeated presentation of a specific sequence establishes a more stable long-term memory, as shown by increased recall accuracy over successive trials of an STM task. Here we used fMRI to study the neural mechanisms that underlie sequence learning in the audit...

We agree with Frost that the variety of orthographies in the world's languages complicates the task of "cracking the orthographic code." Frost suggests that orthographic processing must therefore differ between orthographies. We suggest that the same basic orthographic processes are applied to all languages. Where languages differ is in what the re...

Dividing auditory sequence into groups, or imposing rhythmic, tonal, or spatial structure during presentation, improves recall performance. Several competing computational models have been proposed to account for these effects, but little is known about the neural correlates of grouping and hence the representations that encode grouped sequences. T...

The goal of research on how letter identity and order are perceived during reading is often characterized as one of "cracking the orthographic code." Here, we suggest that there is no orthographic code to crack: Words are perceived and represented as sequences of letters, just as in a dictionary. Indeed, words are perceived and represented in exact...

A method used widely to study the first 250 ms of visual word recognition is masked priming: These studies have yielded a rich set of data concerning the processes involved in recognizing letters and words. In these studies, there is an implicit assumption that the early processes in word recognition tapped by masked priming are automatic, and mask...

Bowers and Davis (2012) criticize Bayesian modelers for telling "just so" stories about cognition and neuroscience. Their criticisms are weakened by not giving an accurate characterization of the motivation behind Bayesian modeling or the ways in which Bayesian models are used and by not evaluating this theoretical framework against specific altern...

In lexical decision, to date few studies in English have found a reliable pseudohomophone priming advantage with orthographically similar primes (the klip-plip effect; Frost, Ahissar, Gotesman, & Tayeb, 2003; see Rastle & Brysbaert, 2006, for a review). On the basis of the Bayseian reader model of lexical decision (Norris, 2006, 2009), we hypothesi...

We investigated the interaction between morphological structure and transposed-letter priming using the same-different task with Hebrew, a Semitic language in which morphology has been shown to play a key role in visual word recognition. In contrast to the results observed with lexical decision (e.g., Velan & Frost, 2009, 2011), a transposed-letter...

Rather than worrying about Bayesian Fundamentalists, I suggest that our real concern should be with Mechanistic Fundamentalists; that is, those who believe that concrete, but frequently untestable mechanisms, should be at the heart of all cognitive theories.

Two experiments used the cross-case same–different task to test whether the orthographically driven morphological decomposition effects that have been found in the lexical decision task are obligatory. Experiment 1 replicated the manipulation used by Duñabeitia, Perea, and Carreiras (2007), testing transposed-letter (TL) priming effects spanning th...

Traditional "activation" views of masked priming explain the identity priming effect in terms of facilitation due to 'pre-activation' of stored representations. Norris and Kinoshita's (2008) Bayesian Reader theory of masked priming instead explains priming in terms of the evidence that the prime contributes towards the decision required to the targ...

Bowers (2010) presented a critique of the account of masked priming presented by Norris and Kinoshita (2008) based on the Bayesian Reader model of visual word recognition (Norris, 2006). In this reply, we point out that: (1) Bowers' criticisms are based on his misunderstanding of both the Bayesian or ideal-observer approach, and the theoretical cla...

Early on during word recognition, letter positions are not accurately coded. Evidence for this comes from transposed-letter (TL) priming effects, in which letter strings generated by transposing two adjacent letters (e.g., jugde) produce large priming effects, more than primes with the letters replaced in the corresponding position (e.g., junpe). D...

We briefly review the considerable evidence for a common ordering mechanism underlying both immediate serial recall (ISR) tasks (e.g. digit span, non-word repetition) and the learning of phonological word forms. In addition, we discuss how recent work on the Hebb repetition effect is consistent with the idea that learning in this task is itself a l...

In the same-different match task, masked priming is observed with the same responses but not different responses. Norris and Kinoshita's (2008) Bayesian reader account of masked priming explains this pattern based on the same principle as that explaining the absence of priming for nonwords in the lexical decision task. The pattern of priming follow...

The strongest support for feedback in speech perception comes from evidence of apparent lexical influence on prelexical fricative-stop compensation for coarticulation. Lexical knowledge (e.g., that the ambiguous final fricative of Christma? should be [s]) apparently influences perception of following stops. We argue that all such previous demonstra...

R. Ratcliff, P. Gomez, and G. McKoon (2004) suggested much of what goes on in lexical decision is attributable to decision processes and may not be particularly informative about word recognition. They proposed that lexical decision should be characterized by a decision process, taking the form of a drift-diffusion model (R. Ratcliff, 1978), that o...

A prime generated by transposing two internal letters (e.g., jugde) produces strong priming of the original word (judge). In lexical decision, this transposed-letter (TL) priming effect is generally weak or absent for nonword targets; thus, it is unclear whether the origin of this effect is lexical or prelexical. The authors describe the Bayesian R...

Comparisons of indirect measures (e.g., subliminal priming) with direct measures (e.g., conscious reports, or prime discriminability) can help elucidate the relationship between nonconscious and conscious perception. We report three experiments on masked word priming in which we observed that priming (RT) decreased with increasing prime visibility...

The authors argue that perception is Bayesian inference based on accumulation of noisy evidence and that, in masked priming, the perceptual system is tricked into treating the prime and the target as a single object. Of the 2 algorithms considered for formalizing how the evidence sampled from a prime and target is combined, only 1 was shown to be c...

A Bayesian model of continuous speech recognition is presented. It is based on Shortlist (D. Norris, 1994; D. Norris, J. M. McQueen, A. Cutler, & S. Butterfield, 1997) and shares many of its key assumptions: parallel competitive evaluation of multiple lexical hypotheses, phonologically abstract prelexical and lexical representations, a feedforward...

Listeners heard an ambiguous /f-s/ in nonword contexts where only one of /f/ or /s/ was legal (e.g., frul/*srul or *fnud/snud). In later categorisation of a phonetic continuum from /f/ to /s/, their category boundaries had shifted; hearing -rul led to expanded /f/ categories, -nud expanded /s/. Thus phonotactic sequence information alone induces pe...

Overview The Hebb repetition effect (Hebb, 1961) is a phenomenon whereby per-formance on the immediate serial recall of a list of familiar items is seen to improve over unannounced repetitions of a given list. One possible real-world counterpart of this effect is the learning of phonological word-forms that are themselves sequences of familiar item...

In this study, we explored capacities for three different aspects of short-term verbal memory in patients with semantic dementia. As expected, the two patients had poor recall for lexico-semantic item information, as assessed by immediate serial recall of word lists. In contrast, their short-term memory for phonological information was preserved, a...

In three experiments, we tested the hypothesis that those errors in immediate serial recall (ISR) that are attributable to phonological confusability share a locus with segmental errors in normal speech production. In the first two experiments, speech errors were elicited in the repeated paced reading of six-letter lists. The errors mirrored the ph...

In this study, we explored capacities for three different aspects of short-term verbal memory in patients with semantic dementia. As expected, the two patients had poor recall for lexico-semantic item information , as assessed by immediate serial recall of word lists. In contrast, their short-term memory for phonological information was preserved,...

In this study, we explored capacities for three different aspects of short-term verbal memory in patients with semantic dementia. As expected, the two patients had poor recall for lexico-semantic item information , as assessed by immediate serial recall of word lists. In contrast, their short-term memory for phonological information was preserved,...