Melissa Duff

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

Purpose The purpose of this viewpoint was to advocate for increased study of semantic memory ability in traumatic brain injury (TBI). Method We review modern conceptualizations of semantic memory and its neural correlates and discuss how common neuroanatomical and cognitive deficits in TBI place this population at an increased risk for semantic di...

Background Memory and learning deficits are among the most impactful and longest-lasting symptoms experienced by people with chronic traumatic brain injury (TBI). Despite the persistence of post-TBI memory deficits and their implications for community reintegration, memory rehabilitation is restricted to short-term care within structured therapy se...

Purpose Traumatic brain injury (TBI) is a leading cause of death and disability among adults in the United States. There is evidence to suggest the peripheral vestibular system is vulnerable to damage in individuals with TBI. However, there are limited prospective studies that describe the type and frequency of vestibular impairment in individuals...

Objective Autobiographical recall can be impoverished in Traumatic Brain Injury (TBI). We explored whether the recall of the TBI event was unique to this trend since the event is both self-defining and traumatic. Methods We recruited 30 non-injured comparison participants (NC) and 30 participants in the chronic phase of a moderate–severe TBI from...

Traumatic brain injury (TBI) can cause a range of cognitive and communication challenges that negatively affect social participation in both face-to-face interactions and computer-mediated communication. In particular, individuals with TBI report barriers that limit access to participation on social media platforms. To improve access to and use of...

This paper presents a model specification for group comparisons regarding a functional trend over time within a trial and learning across a series of trials in intensive binary longitudinal eye-tracking data. The functional trend and learning effects are modeled using by-variable smooth functions. This model specification is formulated as a general...

Introduction: Naming difficulties are commonly reported in the acute- and subacute- stages of recovery of traumatic brain injury (TBI) and across severity levels. Previous studies, however, have used samples of mixed chronicity (acute and chronic) and severity (mild and severe) and then aggregated data across individuals from these distinct groups....

Studies of the impact of brain injury on memory processes often focus on the quantity and episodic richness of those recollections. Here, we argue that the organization of one's recollections offers critical insights into the impact of brain injury on functional memory. It is well‐established in studies of word list memory that free recall of unrel...

Purpose Despite common clinical complaints about memory for conversation after traumatic brain injury (TBI), the nature and severity of this deficit are unknown. In this research note, we report feasibility and preliminary data from a new conversation memory study protocol. Method Participants in this feasibility study were 10 pairs, each includin...

Purpose Traumatic brain injury (TBI) is associated with a range of cognitive-communicative deficits that interfere with everyday communication and social interaction. Considerable effort has been directed at characterizing the nature and scope of cognitive-communication disorders in TBI, yet the underlying mechanisms of impairment are largely unspe...

Objective To examine sleep disruption in chronic traumatic brain injury (TBI) across 3 aims: (1) to examine differences in self-reported sleep disruption between adults with and without a chronic history of TBI; (2) to query reported changes in sleep after TBI; and (3) to explore the relationship between self-reported sleep disruption and memory fa...

Drawing on the social compensation hypothesis, this study investigates whether Facebook use facilitates social connectedness for individuals with traumatic brain injury (TBI), a common and debilitating medical condition that often results in social isolation. In a survey (N = 104 participants; n = 53 with TBI, n = 51 without TBI), individuals with...

Purpose Memory impairments are among the most commonly reported deficits and among the most frequent rehabilitation targets for individuals with traumatic brain injury (TBI). Memory and learning are also critical for rehabilitation success and broader long-term outcomes. Speech-language pathologists (SLPs) play a central role in memory management f...

Purpose Dizziness and imbalance are common symptoms during the acute phase of traumatic brain injury (TBI). However, there is evidence to suggest that these symptoms persist into the chronic phase of injury. Few prospective studies have examined the frequency and type of dizziness and imbalance in adults with chronic moderate–severe TBI. The aim of...

Primary objective: An emerging body of research examines the role of computer-mediated communication in supporting social connection in persons with traumatic brain injury (TBI). We examine the cognitive impacts of engaging with images posted to social media for persons with moderate-severe TBI. Research design: Prior work shows that after viewi...

Objective To examine the relationship between self-report and actigraphy measurement of sleep in people with and without traumatic brain injury (TBI) by addressing 2 aims: (1) to assess the relationship between self-report and actigraphy for sleep quantity in people with and without TBI; and (2) to explore how self-report and actigraphy capture sle...

Traumatic brain injury (TBI) can cause cognitive, communication, and psychological challenges that profoundly limit independence in everyday life. Conversational Agents (CAs) can provide individuals with TBI with cognitive and communication support, although little is known about how they make use of CAs to address injury-related needs. In this stu...

Introduction Several studies have reported impaired emotion recognition in adults with traumatic brain injury (TBI), but studies have two major design features that limit application of results to real-world contexts: (1) participants choose from among lists of basic emotions, rather than generating emotion labels, and (2) images are typically pres...

Purpose: Real-world communication is situated in rich multimodal contexts, containing speech and gesture. Speakers often convey unique information in gesture that is not present in the speech signal (e.g., saying "He searched for a new recipe" while making a typing gesture). We examine the narrative retellings of participants with and without mode...

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 for...

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 enrichment...

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...