Director: Kristie Spencer, Ph.D., CCC-SLP

We are interested in understanding the nature of neurogenic motor speech and cognitive disorders and how best to serve people who experience these disorders.


Current projects include:

Electronic cognitive supports for individuals with dementia from Parkinson's Disease (Summers, lead)

According to the World Health Organization, over 55 million people live with dementia worldwide. Decline in memory, attention, executive functions, orientation, and visuospatial processing is common. These cognitive changes can lead to decreased quality of life, social isolation, caregiver distress, and considerable economic challenges within the family and broader society. Emerging evidence suggests that electronic cognitive aids can reduce dementia burden, increasing orientation, organization, and memory for key information. However, aids are typically designed for persons with mild cognitive impairment, not dementia. IndiAide (Developer, Alyssa Jones) is a private start-up company that intends to address this treatment gap with their electronic, customizable cross-platform software. The patient-facing home screen can be individualized to fit each person’s wants, needs, and abilities. To ensure this prototype meets the needs of families with dementia, it is critical to hear directly from persons with dementia and their caregivers about their desired cognitive support and test the feasibility and usability of the prototype in differing environments. Successful implementation of IndiAide as a therapeutic tool will require knowledge of dementia presentation and progression, best practice, cognitive theories and rehabilitation strategies, and human-centered design. 

The specific aim of this upcoming project is to develop an electronic memory aid for dementia, building on a prototype generated by startup company IndiAide using human-centered design principles. The first objective will determine the most critical needs for cognitive support from the key stakeholders of persons with dementia and their carers. Objective 2 will assess feasibility and usability of the prototype within a controlled environment. Objective 3 will determine feasibility and usability within the home environment of families with dementia. The expected outcome is an updated prototype that incorporates input of a neglected clinical population, individuals with dementia from PD and their caregivers.   


Usability and Feasibility of IndiAide App to Support Cognition in Individuals with Parkinson's Disease (Nir, lead)

The purpose of this upcoming study is to complete usability and feasibility testing on IndiAide (Developer, Alyssa Jones) to determine its applicability to individuals with Mild Cognitive Impairment (MCI) from Parkinson's Disease. This study will be divided into three phases, testing functionality of IndiAide with (1) a neurotypical group and high comfort with electronics, (2) a neurotypical group and low comfort with electronics, and (3) individuals with PD-MCI and a range of comfort levels with electronics. 


Subgroups of ataxic dysarthria (collaborator Kaitlin Lansford, Ph.D., Florida State University)

People with ataxic dysarthria from cerebellar disease can present with a wide range of speech characteristics.  Some speech features can even be contradictory, such as excessive variation of prosody or insufficient variation of prosody. The variability within a single speech diagnosis leads to misdiagnosis, clinical uncertainty, and grouping of disparate speakers for research purposes. We have completed several studies that identify and characterize subgroups within ataxic dysarthria (Spencer & France, 2016; Spencer & Dawson, 2019; Gore & Spencer, 2020; Amaral, Spencer, & Lansford, 2021). Our methodologies have included listener ratings using visual analog scales and, most recently, auditory free classification. To date, most of our speakers have had spinocerebellar ataxia. Future projects will expand the speaker sample/severity/etiologies and add a clinical control group of another dysarthria type. 


The relationship between dysarthria, cognition, and motor profile in Parkinson’s disease (Brown, lead) 

While previously considered purely a motor disorder, Parkinson’s disease (PD) is now recognized as a complex constellation of motor and non-motor symptoms. Current research to better understand the heterogeneity of symptoms has uncovered potential links between motor and non-motor features. Specifically, converging evidence suggests an association between the presence of dysarthria and cognitive decline, and that this relationship may be mediated by primary motor phenotype (i.e., tremor-dominant and non-tremor dominant). Our recent studies suggest that people with PD who have worse speech naturalness and articulatory precision tend to have a non-tremor form of PD. Additionally, our logitudinal study suggested that speech functioning around the time of diagnosis is associated with a non-tremor dominant motor profile, and is predictive of dementia 5-7 years post diagnosis. Findings from both experiments align, in part, with current literature implicating breakdowns in cholinergic-mediated channels, thought to be more severely depleted in individuals with pervasive cognitive decline and a non-tremor presentation, as a possible contributor to dysarthria from PD. More research is needed to better understand these relationships.


Using Smartphone Applications to Support Cognition in Individuals with Parkinson’s Disease: A Pilot Treatment Study (Cornell, Spencer, Sohlberg)

Cognitive impairment is a nonmotor symptom impacting a significant proportion of individuals with Parkinson Disease, even at the time of diagnosis, and is considered a risk factor for Parkinson’s Disease Dementia (PDD; Domellӧf, Ekman, Forsgren, & Elgh, 2015; Pedersen, Larsen, Tysnes, & Alves, 2017; Santangelo et al., 2015). Cognitive impairment not only negatively affects patients’ functional performance in instrumental activities of daily living and reduces participation in social and leisure activities, it also increases financial strain and caregiver burden (Jones et al., 2017; Lawson et al., 2014; Pirogovsky et al., 2014). Therefore, it is important in clinical practice to identify cognitive impairment in individuals with PD and determine intervention strategies that maintain or improve independence and quality of life, which in turn may reduce financial strain and caregiver burden. This study examined the feasibility and impact of a hybrid (individual and small group) treatment study, designed to address the cognitive challenges of PD through the use of smartphones. The treatment program focused on training voice commands to use two primary smartphone features: (i) reminders and (ii) the calendar function. Response to treatment was measured via Goal Attainment Scaling (primary outcome measure) and measures of executive function, depression, and well-being (secondary outcome measures).