Fraser Milton

• University of Exeter

Previous work has shown that deferring feedback significantly impairs two-dimensional information-integration category learning, often thought to recruit an implicit learning system, but leaves intact unidimensional rule-based learning, commonly assumed to engage an explicit system. These results were taken to support the influential COmpetition be...

Flexible, adaptive behaviour depends on the application of prior learning to novel contexts (transfer). Transfer can take many forms, but the focus of the present study was on ‘task schemas’ – learning strategies that guide the earliest stages of engaging in a novel task. The central aim was to examine the architecture of task schemas and determine...

Objective Transient epileptic amnesia (TEA) is a form of adult‐onset epilepsy where presenting features are well described, but little is known regarding prognosis. This study aimed to elucidate the long‐term prognosis of TEA regarding seizure control, memory, medical comorbidities, and life expectancy. Methods Up‐to‐date clinical information was...

Working memory training improves children's cognitive performance on untrained tasks; however, little is known about the underlying neural mechanisms. This was investigated in 32 typically developing children aged 10-14 years (19 girls and 13 boys) using a randomized controlled design and multi-modal magnetic resonance imaging (Devon, UK; 2015-2016...

The inverse base rate effect (IBRE) is a nonrational behavioral phenomenon in predictive learning. Canonically, participants learn that the AB stimulus compound leads to one outcome and that AC leads to another outcome, with AB being presented three times as often as AC. When subsequently presented with BC, the outcome associated with AC is prefere...

Working memory training improves cognitive performance on untrained tasks; however, little is known about the underlying neural mechanisms, particularly in childhood where neuroplasticity may be greatest. The neural correlates of working memory training were investigated in 32 typically developing children aged 10-14 years (19 girls and 13 boys; De...

Although Galton recognized in the 1880s that some individuals lack visual imagery, this phenomenon was mostly neglected over the following century. We recently coined the terms ‘aphantasia’ and ‘hyperphantasia’ to describe visual imagery vividness extremes, unlocking a sustained surge of public interest. Aphantasia is associated with subjective imp...

The term Transient Epileptic Amnesia was coined in 1990 to describe a form of epilepsy causing predominantly amnestic seizures which could be confused with episodes of Transient Global Amnesia. Subsequent descriptions have highlighted its association with ‘atypical’ forms of memory disturbance including accelerated long-term forgetting, disproporti...

Integral stimuli (e.g. colours varying in saturation and brightness) are classically considered to be processed holistically (i.e. as undifferentiated stimulus wholes); people analyze such stimuli into their consistent dimensions only with substantial time, effort, training, or instruction (Foard & Kemler Nelson, 1984). In contrast, Combination The...

Introduction: While short-term cognitive impairment following electroconvulsive therapy (ECT) is well described and acknowledged, the relationship between ECT and persistent memory impairment, particularly of autobiographical memory, has been controversial. Methods: We describe the case of a 70-year-old consultant neurophysiologist, AW, who develop...

In the 3 experiments reported here we show that a specific neurostimulation method, whose influence can be understood in terms of a well-known theory of stimulus representation, is able to affect face recognition skills by impairing participants' performance for upright faces. We used the transcranial Direct Current Stimulation (tDCS) procedure we...

Although Galton recognised in 1880 that some individuals lack visual imagery, this phenomenon was largely neglected over the following century. We recently coined the terms ‘aphantasia’ and ‘hyperphantasia’ to describe visual imagery vividness extremes, unlocking a sustained surge of public interest. Aphantasia is associated with subjective impairm...

Analogical transfer has been previously reported to occur between rule-based, but not information-integration, perceptual category structures (Casale, Roeder, & Ashby, 2012). The current study investigated whether a similar pattern of results would be observed in cross-modality transfer. Participants were trained on either a rule-based structure, o...

Visual imagery typically enables us to see absent items in the mind’s eye. It plays a role in memory, day-dreaming and creativity. Since coining the terms aphantasia and hyperphantasia to describe the absence and abundance of visual imagery, we have been contacted by many thousands of people with extreme imagery abilities. Questionnaire data from 2...

Polymorphous concepts are hard to learn, and this is perhaps surprising because they, like many natural concepts, have an overall similarity structure. However, the dimensional summation hypothesis (Milton and Wills Journal of Experimental Psychology: Learning, Memory and Cognition, 30, 407–415 2004) predicts this difficulty. It also makes a number...

Visual imagery typically enables us to see absent items in the mind’s eye. It plays a role in memory, day-dreaming and creativity. Since coining the terms aphantasia and hyperphantasia to describe the absence and abundance of visual imagery, we have been contacted by many thousands of people with extreme imagery abilities. Questionnaire data from 2...

This article reports results from three experiments that investigate how a particular neuro-stimulation procedure is able, in certain circumstances, to selectively increase the face inversion effect by enhancing recognition for upright faces, and argues that these effects can be understood in terms of the McLaren-Kaye-Mackintosh (MKM) theory of sti...

Polymorphous concepts are hard to learn, and this is perhaps surprising because they, like many natural concepts, have an overall similarity structure. However, the dimensional summation hypothesis (Milton & Wills, 2004) predicts this difficulty. It also makes a number of other predictions about polymorphous concept formation, which are tested here...

Research investigating transfer of strategies between unique tasks with a similar structure has tended to focus on the entire strategy rather than strategic task components. We investigated how different kinds of training affected performance at test where participants classified dot patterns according to their similarity to category templates by e...

This article examines the effect that prior exposure to perceptual stimuli has on the prevalence of overall similarity (family resemblance) categorization. Experiment 1 demonstrated that participants who had previously encountered stimuli produced more overall similarity sorting when asked to free classify them than participants who were preexposed...

Smith and Church (2018) present a “testimonial” review of dissociable learning processes in comparative and cognitive psychology, by which we mean they include only the portion of the available evidence that is consistent with their conclusions. For example, they conclude that learning the information-integration category-learning task with immedia...

The Inverse Base Rate effect (IBRE; Medin & Edelson, 1988) is a non-rational behavioral phenomenon in predictive learning. Canonically, participants learn that the AB stimulus compound leads to one outcome and that AC leads to another outcome, with AB being presented three times as often as AC. When subsequently presented with BC, the outcome assoc...

Working memory training has been shown to improve performance on untrained working memory tasks in typically developing children, at least when compared to non‐adaptive training; however, there is little evidence that it improves academic outcomes. The lack of transfer to academic outcomes may be because children are only learning skills and strate...

Analogical transfer occurs when someone transfers insights about shared structure from one task to another. Here, we explore this ability in categorization tasks. Previous work found that people could transfer knowledge between two unidimensional rule-based tasks, but could not for two information-integration tasks. In four experiments, we extended...

This paper describes an innovative use of Lesson Study (LS), an internationally used collaborative approach in which teachers develop their teaching knowledge and practices. It aimed to evaluate how EPs join teachers in LS teams, using working memory and other knowledge to inform the teaching of pupils with learning difficulties. The study uses a c...

Behavioral evidence for the COVIS dual‐process model of category learning has been widely reported in over a hundred publications (Ashby & Valentin, 2016). It is generally accepted that the validity of such evidence depends on the accurate identification of individual participants' categorization strategies, a task that usually falls to Decision Bo...

Visual imagery is a form of sensory imagination, involving subjective experiences typically described as similar to perception, but which occur in the absence of corresponding external stimuli. We used the Activation Likelihood Estimation algorithm (ALE) to identify regions consistently activated by visual imagery across 40 neuroimaging studies, th...

Using the Vividness of Visual Imagery Questionnaire we selected 14 high-scoring and 15 low-scoring healthy participants from an initial sample of 111 undergraduates. The two groups were matched on measures of age, IQ, memory and mood but differed significantly in imagery vividness. We used fMRI to examine brain activation while participants looked...

Objective Accelerated long-term forgetting (ALF) occurs when newly learned information decays faster than normal over extended delays. It has been recognised most frequently in temporal lobe epilepsy, including Transient Epileptic Amnesia (TEA), but can also be drug-induced. Little is known about the evolution of ALF over time and its impacts upon...

In the phenomenon of transfer along a continuum (TAC), initial training on easy items facilitates later learning of a harder discrimination. TAC is a widely replicated cross-species phenomenon that is well predicted by certain kinds of associative theory (e.g., Sutherland & Mackintosh, 1971). A recent report of an approximately-opposite phenomenon...

This article presents an evaluation of distance technology used in a novel Lesson Study (LS) approach involving a dispersed LS team for inter-professional purposes. A typical LS model with only school teachers as team members was modified by including university-based lecturers with the school-based teachers, using video-conferencing and online vid...

Working memory training has received a great deal of scientific interest for its potential to enhance general cognitive functioning and children’s academic achievement. Meta-analyses have demonstrated that training reliably improves working memory (WM), and evidence from neuroimaging studies support the notion that this is a result of functional an...

Although instructions often emphasize categories (e.g., odd number → left hand response) rather than specific stimuli (e.g., 3 → left hand response), learning is often interpreted in terms of stimulus-response (S-R) bindings or, less frequently, stimulus-classification (S-C) bindings with little attention being paid to the importance of category-re...

The idea that there are multiple learning systems has become increasingly influential in recent years, with many studies providing evidence that there is both a quick, similarity-based or feature-based system and a more effortful rule-based system. A smaller number of imaging studies have also examined whether neurally dissociable learning systems...

Objective: While olfactory hallucinations are relatively rare in epilepsy, a high prevalence (up to 42%) has been reported in one form - Transient Epileptic Amnesia (TEA). TEA is characterized by recurring amnestic seizures and is commonly associated with persistent interictal memory deficits. Despite reports of changes in smell, olfactory ability...

Purpose – It is argued that the issues of translating basic science, including knowledge from neuroscience, into relevant teaching are similar to those that have been experienced over a long period by educational psychology. This paper proposes that such a translation might be achieved through lesson study (LS), which is an increasingly used techni...

The influential competition between verbal and implicit systems (COVIS) model proposes that category learning is driven by two competing neural systems-an explicit, verbal, system, and a procedural-based, implicit, system. In the current fMRI study, participants learned either a conjunctive, rule-based (RB), category structure that is believed to e...

Some argue that category learning is mediated by two competing learning systems: one explicit, one implicit (Ashby et al., 1998). These systems are hypothesised to be responsible for learning rule-based and information-integration category structures respectively. However, little experimental work has directly investigated whether people are consci...

We describe a patient in whom long-term, therapeutic infusion of the selective gamma-amino-butyric acid type B (GABAB) receptor agonist, baclofen, into the cerebrospinal fluid (CSF) gave rise to three distinct varieties of memory impairment: i) repeated, short periods of severe global amnesia, ii) accelerated long-term forgetting (ALF), evident ove...

Does cognition begin with an undifferentiated stimulus whole, which can be divided into distinct attributes if time and cognitive resources allow (Differentiation Theory)? Or does it begin with the attributes, which are combined if time and cognitive resources allow (Combination Theory)? Across psychology, use of the terms analytic and non-analytic...

The effects of two different types of training on rule-based and information-integration category learning were investigated in two experiments. In observational training, a category label is presented, followed by an example of that category and the participant's response. In feedback training, the stimulus is presented, the participant assigns it...

Newell & Shanks (N&S) argue against the idea that any significant role for unconscious influences on decision making has been established by research to date. Inasmuch as this conclusion applies to the idea of an "intelligent cognitive unconscious," we would agree. Our concern is that the article could lead the unwary to conclude that there are no...

The experience of reading varies markedly between differing texts which may be, for example, primarily informative, musical, or moving.We asked whether these differences would correspond to widespread contrasts in brain activity. Using fMRI, we examined brain activation in expert participants reading passages of prose and poetry. Both prose and poe...

Transient Epileptic Amnesia (TEA) is a recently defined subtype of temporal lobe epilepsy, principally affecting people in middle age with a male predominance. Its key manifestation is the occurrence of recurring episodes of transient amnesia, usually lasting less than an hour and often occurring on waking. One-third of patients have exclusively am...

Transient epileptic amnesia (TEA) is a recently recognized form of temporal lobe epilepsy which is often associated with persistent interictal impairment of autobiographical memory. We used fMRI to investigate the neural basis of this deficit. Eleven patients with TEA, who had no significant deficits on standard tests of anterograde memory, and 17...

Objective: To identify the neural basis of autobiographical memory deficits in transient epileptic amnesia (TEA). Method: 11 people (mean age: 65.91; SD=7.63) diagnosed with transient epileptic amnesia, all of whom complained of extensive autobiographical memory loss, and 17 age and IQ matched controls were recruited. Participants were matched on...

It is sometimes argued that the implementation of an overall similarity classification is less effortful than the implementation of a single-dimension classification. In the current article, we argue that the evidence securely in support of this view is limited, and report additional evidence in support of the opposite proposition-overall similarit...

Eye movements of twelve Caucasian participants were measured whilst they performed a recognition test of same (Caucasian) and other race (Indian) faces. We observed a standard other-race effect, with more items recognised correctly, fewer false alarms, and reduced reaction time to same-race than other-race faces. Additionally, a differential patter...

An influential multi-process model of category learning, COmpetition between Verbal and Implicit Systems (COVIS), suggests that a verbal or a procedural category learning process is adopted, depending on the nature of the learning problem. While the architectural assumptions of COVIS have been widely supported, there is still uncertainty regarding...

We used a novel automatic camera, SenseCam, to create a recognition memory test for real-life events. Adapting a 'Remember/Know' paradigm, we asked healthy undergraduates, who wore SenseCam for 2 days, in their everyday environments, to classify images as strongly or weakly remembered, strongly or weakly familiar or novel, while brain activation wa...

We used a novel automatic camera, SenseCam, to investigate recognition memory for real-life events at a 5-month retention interval. Using fMRI we assessed recollection and familiarity memory using the remember/know procedure. Recollection evoked no medial temporal lobe (MTL) activation compared to familiarity and new responses. Instead, recollectio...

The effects of picture manipulations on humans' and pigeons' performance were examined in a go/no-go discrimination of two perceptually similar categories, cat and dog faces. Four types of manipulation were used to modify the images. Mosaicization and scrambling were used to produce degraded versions of the training stimuli, while morphing and cell...

A free classification study is presented in which the effect of time pressure and the spatial integration of the stimulus dimensions on overall similarity sorting is investigated. A 2 x 2 between-subjects factorial design was employed with the factors being the level of time pressure (high/low) and the spatial integration of the stimulus dimensions...

Aims Transient epileptic amnesia (TEA) is a recently recognised form of temporal lobe epilepsy in which sufferers often complain of irretrievable loss of remote memories. We aimed to answer the following questions: 1) What is the extent and nature of the autobiographical memory loss? 2) Is there impairment of personal semantic and public semantic m...

Aims An exploratory study examining the neural networks involved in reading different genres of text. Methods This functional MRI study recruited 12 skilled readers who teach English literature at Exeter University. Participants were randomly presented with eight examples of each of 5 types of text: technical prose (condition 1), literary prose (2...

Transient Epileptic Amnesia (TEA) is a form of temporal lobe epilepsy associated with ictal and interictal memory disturbance. Some patients with TEA exhibit Accelerated Long-term Forgetting (ALF), in which memory for verbal and non-verbal material is retained normally over short delays but fades at an unusually rapid rate over days to weeks. This...

Transient epileptic amnesia is a form of temporal lobe epilepsy in which sufferers often complain of irretrievable loss of remote memories. We used a broad range of memory tests to clarify the extent and nature of the remote memory deficits in patients with transient epileptic amnesia. Performance on standard tests of anterograde memory was normal....

The ability to group stimuli into meaningful categories is fundamental to natural behavior. Raw perceptions would be useless without an ability to classify items as, for example, threat or food. Previous work suggests that people have a tendency to group stimuli either on the basis of a single dimension or by overall similarity (e.g., Milton, F.N.,...

Two free classification experiments that investigate the persistence of sort strategy are reported. Participants tend to persist with their initial categorization type (family resemblance or unidimensional) for the remaining sorts, overriding the effects of otherwise influential stimulus properties. Sort type was found to persist even after a one-w...

The processes of overall similarity sorting were investigated in 5 free classification experiments. Experiments 1 and 2 demonstrated that increasing time pressure can reduce the likelihood of overall similarity categorization. Experiment 3 showed that a concurrent load also reduced overall similarity sorting. These findings suggest that overall sim...

It has been demonstrated that when people free classify stimuli presented simultaneously in an array, they have a preference to categorize by a single dimension. However, when people are encouraged to categorize items sequentially, they sort by "family resemblance," grouping by overall similarity. The present studies extended this research, produci...

The impact of perceptual difficulty on the prevalence of family resemblance sorting was investigated in a free classification experiment. There were two between-subject conditions, high perceptual difficulty and low perceptual difficulty and participants were asked to sort the stimuli into two groups in the way that seemed most appropriate to them....

A free classification study is presented that uses eye-tracking to better characterize the strategies that are employed in the creation of overall similarity and single-dimension categories. The number of fixations across the dimensions and the proportion of dimensions fixated were significantly greater for overall similarity sorters than for singl...

Response tempo and separable-integral responding: Evidence for an integral-to-separable processing sequence in visual perception. Journal of Experimental Psychology: Human Perception and Performance, 9, 103-112. Previous work suggests many natural categories are organised around an overall similarity (OS) structure (Rosch & Mervis, 1975). However,...