Melissa Duff

Vanderbilt University | Vander Bilt · Department of Hearing and Speech Sciences

Background: Facial emotion recognition deficits are common after moderate-severe traumatic brain injury (TBI) and linked to poor social outcomes. We examine whether emotion recognition deficits extend to facial expressions depicted by emoji. Methods: Fifty-one individuals with moderate-severe TBI (25 female) and fifty-one neurotypical peers (26...

Word learning is an iterative and dynamic process supported by multiple neural and cognitive systems. Converging evidence from behavioral, cellular, and systems neuroscience highlights sleep as an important support for memory and word learning over time. In many lab-based word learning experiments, participants encode and subsequently retrieve newl...

Background Adults with traumatic brain injury (TBI) report significant barriers to using current social media platforms, including cognitive overload and challenges in interpreting social cues. Rehabilitation providers may be tasked with helping to address these barriers. Objectives To develop technological supports to increase social media access...

Scientists who study the brain try to understand how it performs everyday behaviors like language, memory, and emotion. Scientists learn a lot by studying how these behaviors change when the brain is damaged. Over the past 200 years, they have made many discoveries by studying individuals with brain damage. For example, one patient could not form s...

Purpose The purpose of this viewpoint is to advocate for increased study of word learning abilities and word learning interventions in traumatic brain injury (TBI). Method We describe the word learning process and the unique opportunities afforded by studying each component and stage. Building on discussions at the 2022 International Cognitive-Com...

Purpose: The dual goals of this tutorial are (a) to increase awareness and use of mediation and moderation models in cognitive-communication rehabilitation research by describing options, benefits, and attainable analytic approaches for researchers with limited resources and sample sizes and (b) to describe how these findings may be interpreted fo...

Speakers design communication for their audience, providing more information in both speech and gesture when their listener is naïve to the topic. We test whether the hippocampal declarative memory system contributes to multimodal audience design. The hippocampus, while traditionally linked to episodic and relational memory, has also been linked to...

Introduction: Temporal order memory is a core cognitive function that underlies much of our behavior. The ability to bind together information within and across events, and to reconstruct that sequence of information, critically relies upon the hippocampal relational memory system. Recent work has suggested traumatic brain injury (TBI) may particu...

Social network size has been associated with complex socio-cognitive processes (e.g., memory, perspective taking). Supporting this idea, recent neuroimaging studies in healthy adults have reported a relationship between social network size and brain volumes in regions related to memory and social cognition (e.g., hippocampus, amygdala). Lesion-defi...

Background A critical gap in our knowledge about social media is whether we can alleviate accessibility barriers and challenges for individuals with traumatic brain injury (TBI), to improve their social participation and health. To do this, we need real-time information about these barriers and challenges, to design appropriate aids. Objective The...

Background and aim Deficits in decision-making are a common consequence of moderate-severe traumatic brain injury (TBI). Less is known, however, about how individuals with TBI perform on moral decision-making tasks. To address this gap in the literature, the current study probed moral decision-making in a sample of individuals with TBI using a wide...

The number of individuals affected by traumatic brain injury (TBI) is growing globally. TBIs may cause a range of physical, cognitive, and psychiatric deficits that can negatively impact employment, academic attainment, community independence, and interpersonal relationships. Although there has been a significant decrease in the number of injury re...

Purpose When we speak, we gesture, and indeed, persons with aphasia gesture more frequently. The reason(s) for this is still being investigated, spurring an increase in the number of studies of gesture in persons with aphasia. As the number of studies increases, so too does the need for a shared set of best practices for gesture research in aphasia...

Background Individuals with a history of traumatic brain injury (TBI) report fewer social contacts, less social participation, and more social isolation than noninjured peers. Cognitive-communication disabilities may prevent individuals with TBI from accessing the opportunities for social connection afforded by computer-mediated communication, as i...

Object naming involves accessing meaning and retrieving the associated word form from remote semantic memory. Historically, previously acquired semantic knowledge (i.e., remote semantic memory) was thought to be independent of the hippocampus via neocortical consolidation. This view is based on evidence demonstrating a dissociation in behavior in p...

Unexpected absence of aphasia after left-hemisphere perisylvian damage is often assumed to reflect right-hemisphere language lateralization, but other potential explanations include bilateral language representation, or sparing of critical left-hemisphere regions due to individual variability. We describe the case of a left-handed gentleman who pre...

Purpose: When we speak, we gesture, and indeed, persons living with aphasia gesture more frequently. The reason(s) for this is still being investigated, spurring an increase in the number of studies of gesture usage by persons living with aphasia. As the number of studies increase, so too does the need for a shared set of standards and best practic...

Purpose The purpose of this article is to highlight the need for increased focus on cognitive communication in North American speech-language pathology graduate education models. Method We describe key findings from a recent survey of acute care speech-language pathologists (SLPs) in the United States and expand upon the ensuing discussion at the...

Purpose In both basic science and intervention research in traumatic brain injury (TBI), heterogeneity in the patient population is frequently cited as a limitation and is often interpreted as a factor reducing certainty in the generalizability of research findings and as a source of conflicting findings across studies. Historically, much of TBI re...

Objective To identify the consequences of the COVID-19 pandemic for individuals with traumatic brain injury (TBI), with particular attention to unique effects for individuals with chronic disability. Design Individuals with and without a history of TBI completed a web-based survey. Setting Participants were recruited from the Vanderbilt Brain Inj...

In the movies, many characters heal very quickly after getting hurt. Some, like Wolverine or Rapunzel, even have special healing powers. However, when a person gets hurt in real life, it may take a lot of patience and hard work to get better. People who are recovering from an injury may also need support from the community and care from healthcare...

Recent findings point to a role for hippocampus in the moment-by-moment processing of language, including the use and generation of semantic features in certain contexts. What role the hippocampus might play in the processing of semantic relations in spoken language comprehension, however, is unknown. Here we test patients with bilateral hippocampa...

Primary objective: To characterize current knowledge, beliefs, confidence, and practice patterns of acute care speech-language pathologists (SLPs) in assessing and managing cognitive-communication disorders following traumatic brain injury (TBI). Research design: We developed an online survey to learn more about current TBI knowledge and practic...

INTRODUCTION: The study of language has often privileged the verbal modality and face-to-face interaction. However, real life communication is multi-modal and frequently occurs in situations where visibility is restricted (e.g., talking on the phone). We examine how the speech and gesture of people with amnesia and healthy comparison participants v...

When people talk, they gesture. Gesture is a fundamental component of language that contributes meaningful and unique information to a spoken message and reflects the speaker’s underlying knowledge and experiences. Theoretical perspectives of speech and gesture propose that they share a common conceptual origin and have a tightly integrated relatio...

Memory deficits are a common and frequently-cited consequence of moderate-severe traumatic brain injury (TBI). However, we know less about how TBI influences relational memory, which allows the binding of the arbitrary elements of experience and the flexible use and recombination of relational representations in novel situations. Relational memory...

Primary Objective: The current study examined how creative divergent thinking (i.e., the ability to produce varied and original solutions to a problem) is impacted by moderate-to-severe traumatic brain injury (TBI). Research Design: Descriptive, observational. Methods and Procedures: We administered two tasks of divergent thinking, the Abbreviated...

Purpose This tutorial aims to draw attention to the interactions among memory, sleep, and therapy potential and to increase awareness and knowledge in the field of speech-language pathology of the potential impact of sleep as a mediating or moderating factor in promoting therapeutic outcome. Method We highlight key findings from the literature on...

A growing body of literature has examined sex differences in a variety of outcomes from moderate-severe traumatic brain injury (TBI), including outcomes for social functioning. Social functioning is an area in which adults with TBI have significant long-term challenges (1–4), and a better understanding of sex and gender differences in this domain m...

Since Tulving proposed a distinction in memory between semantic and episodic memory, considerable effort has been directed towards understanding their similar and unique features. Of particular interest has been the extent to which semantic and episodic memory have a shared dependence on the hippocampus. In contrast to the definitive evidence for t...

Word learning requires learners to bind together arbitrarily-related phonological, visual, and conceptual information. Prior work suggests that this binding can be robustly achieved via incidental cross-situational statistical exposure to words and referents. When cross-situational statistical learning (CSSL) is tested in the laboratory, there is n...

Objective: The aim of this study was to determine the health utility states of the most commonly used traumatic brain injury (TBI) clinical trial endpoint, the Extended Glasgow Outcome Scale (GOSE). Summary background data: Health utilities represent the strength of one's preferences under conditions of uncertainty. There are insufficient data t...

Referring to things in the world - that woman, her idea, she - is a central component of language. Understanding reference requires the listener to keep track of the unfolding discourse history while integrating multiple sources of information to interpret the speech stream as it unfolds in time. Pronouns are a common way to establish reference. Bu...

A recent neuropsychological study found that amnesic patients with hippocampal damage (HP) and severe declarative memory impairment produce markedly fewer responses than healthy comparison (CO) participants in a semantic feature generation task (Klooster and Duff, 2015), consistent with the idea that hippocampal damage is associated with semantic c...

Introduction: Relational memory is the ability to bind arbitrary relations between elements of experience into durable representations and the flexible expression of these representations. It is well known that individuals with traumatic brain injury (TBI) have declarative memory impairments, but less is known about how TBI affects relational memor...

The neural mechanisms that support synchrony of conversational behaviors (e.g., word production, turn length) are not well understood. Lesion work has suggested that the ventromedial prefrontal cortex (vmPFC) is important for noncontent speech convergence, which measures if word production becomes more similar across a conversation (Gordon, Tranel,...

The impact of traumatic brain injury (TBI) on procedural memory has received significantly less attention than declarative memory. Although to date studies on procedural memory have yielded mixed findings, many rehabilitation protocols (e.g., errorless learning) rely on the procedural memory system, and assume that it is relatively intact. The aim...

Background: Adults with traumatic brain injury (TBI) report loss of friendship and reduced social participation after injury, but there is limited information regarding quantity of friends and methods of communication. Our objective was to characterize friendship networks, social participation, and methods of communication, including computer-medi...

Facial affect recognition deficits following traumatic brain injury (TBI) have been well documented, as has their relationship with impairment in several other cognitive domains. However, little is known about the neurobiological mechanisms underlying affect recognition deficits, in particular mechanisms underlying different aspects of facial affec...

Rapid word learning without the hippocampus is an alluring prospect – it holds the promise of remediating a common learning deficit associated with aging (healthy or pathological) and certain neurological conditions. Despite recent reports indicating rapid, non-hippocampal word learning by amnesic adults after contrastive ‘fast-mapping’ exposure, s...

When we communicate, we alter our language and gesture based on the mutually shared knowledge – common ground – that we have with our listener. How memory supports these alterations remain unclear. We asked healthy adults and patients with hippocampal amnesia to engage in a referential communication task. Previous work suggests that common ground c...

Objectives: Although individuals with traumatic brain injury (TBI) often report higher levels of social isolation, little is known about the factors influencing their self-perception of loneliness. The aim of the current study was to investigate the relationship between loneliness, social network size, and personality variables (neuroticism and ex...

Objectives: The objective of this study was to examine the effects of traumatic brain injury (TBI) and age on facial emotion recognition abilities in adults. Age and TBI were expected to have negative effects on emotion recognition and a TBI by age interaction was hypothesized such that older adults with TBI would have the lowest emotion recogniti...

Purpose: Research manipulating the complexity of housing environments for healthy and brain-damaged animals has offered strong, well-replicated evidence for the positive impacts in animal models of enriched environments on neuroplasticity and behavioral outcomes across the lifespan. This article reviews foundational work on environmental enrichmen...

Primary Objective: Research studies and clinical observations of individuals with traumatic brain injury (TBI) indicate marked deficits in mentalizing—perceiving social information and integrating it into judgements about the affective and mental states of others. The current study investigates social-cognitive mechanisms that underlie mentalizing...

Adults with traumatic brain injury (TBI) often report reduced social participation and loss of friends, but little is known about quality of friendship after TBI. Our objective was to characterize social participation, friendship quantity, and friendship quality of adults with TBI and a comparison group of uninjured adults. Participants included 18...

It is well established that the hippocampus is critical for memory. Recent evidence suggests that one function of hippocampal memory processing is to optimize how people actively explore the world. Here we demonstrate that the link between the hippocampus and exploration extends even to the moment-to-moment use of eye movements during visuospatial...

The character Dory from Finding Nemo has a memory problem. Poor Dory has a hard time remembering anything. She forgets who her family is and what has happened in her life. In just a couple of minutes, she forgets the things that her friends say to her. Movie makers are trying to show what amnesia, a type of memory loss, is like. However, real-life...

Although facial affect recognition deficits are well documented in individuals with moderate-to-severe traumatic brain injury (TBI), little research has examined the neural mechanisms underlying these impairments. Here, we use diffusion tensor imaging (DTI), specifically the scalars fractional anisotropy (FA), mean diffusivity (MD), and radial diff...

Objective: While deficits in several cognitive domains following moderate-to-severe traumatic brain injury (TBI) have been well documented, little is known about the impact of TBI on creativity. In the current study, our goal is to determine whether convergent problem solving, which contributes to creative thinking, is impaired following TBI. Met...

During conversation, people integrate information from co-speech hand gestures with information in spoken language. For example, after hearing the sentence, "A piece of the log flew up and hit Carl in the face" while viewing a gesture directed at the nose, people tend to later report that the log hit Carl in the nose (information only in gesture) r...

Verb bias-the co-occurrence frequencies between a verb and the syntactic structures it may appear with-is a critical and reliable linguistic cue for online sentence processing. In particular, listeners use this information to disambiguate sentences with multiple potential syntactic parses (e.g., Feel the frog with the feather.). Further, listeners...

Converging evidence points to a role for the hippocampus in statistical learning, but open questions about its necessity remain. Evidence for necessity comes from Schapiro and colleagues who report that a single patient with damage to hippocampus and broader medial temporal lobe cortex was unable to discriminate new from old sequences in several st...

Objective: To examine the relationship between facial-affect recognition and different aspects of self- and proxy-reported social-communication impairment following moderate-severe traumatic brain injury (TBI). Method: Forty-six adults with chronic TBI (>6 months postinjury) and 42 healthy comparison (HC) adults were administered the La Trobe Co...

Verb bias--the co-occurrence frequencies between a verb and the syntactic structures it may appear with--is a critical and reliable linguistic cue for online sentence processing. In particular, listeners use this information to disambiguate sentences with multiple potential syntactic parses (e.g., Feel the frog with the feather.). Further, listener...

Verb bias--the co-occurrence frequencies between a verb and the syntactic structures it may appear with--is a critical and reliable linguistic cue for online sentence processing. In particular, listeners use this information to disambiguate sentences with multiple potential syntactic parses (e.g., Feel the frog with the feather.). Further, listener...

It is well established that many individuals with traumatic brain injury (TBI) are impaired at facial affect recognition, yet little is known about the mechanisms underlying such deficits. In particular, little work has examined whether the breakdown of facial affect recognition abilities occurs at the perceptual level (e.g., recognizing a smile) o...

The ability to flexibly combine existing knowledge in response to novel circumstances is highly adaptive. However, the neural correlates of flexible associative inference are not well characterized. Laboratory tests of associative inference have measured memory for overlapping pairs of studied items (e.g., AB, BC) and for nonstudied pairs with comm...

Co-speech hand gesture facilitates learning and memory, yet the cognitive and neural mechanisms supporting this remain unclear. One possibility is that motor information in gesture may engage procedural memory representations. Alternatively, iconic information from gesture may contribute to declarative memory representations mediated by the hippoca...

Objective: To replicate a previous study of Theory of Mind (ToM) task performance in adults with traumatic brain injury (TBI) under different working memory (WM) demands, and determine if there are sex-based differences in effects of WM load on ToM task performance. Method: 58 adults with moderate-severe TBI (24 females) and 66 uninjured adults...

Converging evidence points to a role for the hippocampus in statistical learning, but open questions about its necessity remain. Evidence for necessity comes from Schapiro and colleagues who report that a single patient with damage to hippocampus and broader medial temporal lobe cortex was unable to discriminate new from old sequences in several st...

Hippocampal involvement in learning and remembering relational information has an extensive history, often focusing specifically on spatial information. In humans, spatial reconstruction (SR) paradigms are a powerful tool for evaluating an individuals' spatial-relational memory. In SR tasks, participants study locations of items in space and subseq...

Hippocampal functioning contributes to our ability to generate multifaceted, imagistic event representations. Patients with hippocampal damage produce event narratives that contain fewer details and fewer imagistic features. We hypothesized that impoverished memory representations would influence language at the word level, yielding words lower in...

Successful communication requires keeping track of what other people do and do not know, and how this differs from our own knowledge. Here we ask how knowledge of what others know is stored in memory. We take a neuropsychological approach, comparing healthy adults to patients with severe declarative memory impairment (amnesia). We evaluate whether...

This chapter summarizes cognitive aging findings focused on memory abilities, and addresses language abilities. It presents several relevant theories of cognitive aging that are applicable to the study of memory, language, or both. The chapter describes the taxonomy of memory to illustrate the organization of human memory systems. It also describes...

Objectives: Written text contains verbal immediacy cues - word form or grammatical cues that indicate positive attitude or liking toward an object, action, or person. We asked if adults with moderate-severe traumatic brain injury (TBI) would respond to these cues, given evidence of TBI-related social communication impairments. Methods: 69 adults wi...

Recent advances in understanding the functionality of the human hippocampus has led to a number of proposals for how hippocampus may support a range of cognitive abilities beyond memory. Building on these advances, we offered a new account of the memory-language interface [Duff and Brown-Schmidt (Front Hum Neurosci 6:69, 2012)]. We proposed that th...

Purpose: The goals of this review paper are to present an overview of the literature on resilience in adults with ABI, to describe approaches to measuring resilience in clinical practice and to discuss practical suggestions for promoting resilience in rehabilitation of adults with ABI. Method: We employed systematic review of journal articles, b...

The hippocampus has long been considered a critical substrate in the neurobiology, neuropsychology, and cognitive neuroscience of memory. Over the past few decades, a number of ground-breaking theoretical and methodological advances have radically enhanced our understanding of the structure and function of the hippocampus and revolutionized the neu...

Recognition of facial affect has been studied extensively in adults with and without traumatic brain injury (TBI), mostly by asking examinees to match basic emotion words to isolated faces. This method may not capture affect labelling in everyday life when faces are in context and choices are open-ended. To examine effects of context and response f...

Language processing requires us to encode linear relations between acoustic forms and map them onto hierarchical relations between meaning units. Such relational binding of linguistic elements might recruit the hippocampus given its engagement by similar operations in other cognitive domains. Historically, hippocampal engagement in online language...

Although several studies have demonstrated that facial-affect recognition impairment is common following moderate-severe traumatic brain injury (TBI), and that there are diffuse alterations in large-scale functional brain networks in TBI populations, little is known about the relationship between the two. Here, in a sample of 26 participants with T...

New research suggests that the same hippocampal computations used in support of memory are also used for language processing, providing direct neurophysiological evidence of a shared neural mechanism for memory and language. This work expands classic memory and language models and represents a new opportunity for studying the memory–language interf...

During communication, we form assumptions about what our communication partners know and believe. Information that is mutually known between the discourse partners-their common ground-serves as a backdrop for successful communication. Here we present an introduction to the focus of this topic, which is the role of memory in common ground and langua...

Verbs often participate in more than 1 syntactic structure, but individual verbs can be biased in terms of whether they are used more often with 1 structure or the other. For instance, in a sentence such as “Bop the bunny with the flower,” the phrase “with the flower” is more likely to indicate an instrument with which to “bop,” rather than which “...

Spontaneous co-speech hand gestures provide a visuospatial representation of what is being communicated in spoken language. Although it is clear that gestures emerge from representations in memory for what is being communicated (De Ruiter, 1998; Wesp, Hesse, Keutmann, & Wheaton, 2001), the mechanism supporting the relationship between gesture and m...

Objectives: Although it has been well documented that traumatic brain injury (TBI) can result in communication impairment, little work to date has examined the relationship between social communication skills and structural brain integrity in patients with TBI. The aim of the current study was to investigate the association between self- and other...

Although moderate to severe traumatic brain injury (TBI) leads to facial affect recognition impairments in up to 39% of individuals, protective and risk factors for these deficits are unknown. The aim of the current study was to examine the effect of sex on emotion recognition abilities following TBI. We administered two separate emotion recognitio...

To investigate the role of episodic thought about the past and future in moral judgment, we administered a well-established moral judgment battery to individuals with hippocampal damage and deficits in episodic thought (insert Greene et al. 2001). Healthy controls select deontological answers in high-conflict moral scenarios more frequently when th...

Creativity relies on a diverse set of cognitive processes associated with distinct neural correlates, and one important aspect of creativity, divergent thinking, has been associated with the hippocampus. However, hippocampal contributions to another important aspect of creativity, convergent problem solving, have not been investigated. We tested th...