- Baltimore, Maryland, United States
Donna Tippett
Johns Hopkins University School of Medicine, Otolaryngology, Faculty Member
Objective:To determine the contribution of white matter hyperintensities (WMH) to language deficits while accounting for cortical atrophy in individuals with primary progressive aphasia (PPA).Method:Forty-three individuals with PPA... more
Objective:To determine the contribution of white matter hyperintensities (WMH) to language deficits while accounting for cortical atrophy in individuals with primary progressive aphasia (PPA).Method:Forty-three individuals with PPA completed neuropsychological assessments of nonverbal semantics, naming, and sentence repetition plus T2-weighted and fluid-attenuated inversion recovery scans. Using three visual scales, we rated WMH and cerebral ventricle size for both scan types. We used Spearman correlations to evaluate associations between the scales and scans. To test whether visual ratings—particularly of WMH—are associated with language, we compared a base model (including gray matter component scores obtained via principal component analysis, age, and days between assessment and MRI as independent variables) with full models (ie, the base model plus visual ratings) for each language variable.Results:Visual ratings were significantly associated within and between scans and were significantly correlated with age but not with other vascular risk factors. Only the T2 scan ratings were associated with language abilities. Specifically, controlling for other variables, poorer naming was significantly related to larger ventricles (P = 0.033) and greater global (P = 0.033) and periventricular (P = 0.049) WMH. High global WMH (P = 0.034) were also correlated with worse sentence repetition skills.Conclusion:Visual ratings of global brain health were associated with language deficits in PPA independent of cortical atrophy and age. While WMH are not unique to PPA, measuring WMH in conjunction with cortical atrophy may elucidate more accurate brain structure–behavior relationships in PPA than cortical atrophy measures alone.
Research Interests:
Background and Objectives Primary progressive aphasia (PPA) is a neurodegenerative condition that predominantly impairs language. Most investigations of how focal atrophy affects language consider 1 time point compared with healthy... more
Background and Objectives Primary progressive aphasia (PPA) is a neurodegenerative condition that predominantly impairs language. Most investigations of how focal atrophy affects language consider 1 time point compared with healthy controls. However, true atrophy quantification requires comparing individual brains over time. In this observational cohort study, we identified areas where focal atrophy was associated with contemporaneous decline in naming in the same individuals. Methods Cross-sectional analyses–related Boston Naming Test (BNT) performance and volume in 22 regions of interests (ROIs) at each time point using Least Absolute Shrinkage and Selection Operator (LASSO) regression. Longitudinal analysis evaluated changes in BNT performance and change in volume in the same ROIs. Results Participants (N = 62; 50% female; mean age = 66.8 ± 7.4 years) with PPA completed the BNT and MRI twice (mean = 343.9 ± 209.0 days apart). In cross-sectional left inferior frontal gyrus pars opercularis, superior temporal pole, middle temporal gyrus, and inferior temporal gyrus were identified as critical for naming at all time points. Longitudinal analysis revealed that increasing atrophy in the left supramarginal gyrus and middle temporal pole predicted greater naming decline, as did female sex and longer intervals between time points. Discussion Although cross-sectional analyses identified classic language areas that were consistently related to poor performance at multiple time points, it was not increasing atrophy in these areas that lead to further decline: longitudinal analysis of each person's atrophy over time instead identified nearby but distinct regions where increased atrophy was related to decreasing performance. The results demonstrate that directly examining atrophy (in each individual) over time furthers understanding of decline in PPA and reveal the importance of left supramarginal gyrus and middle temporal pole in maintaining naming when areas normally critical for language degenerate. The novel results provide insight into how the underlying disease progresses to result in the clinical decline in naming, the deficit most common among all 3 PPA variants.
Research Interests:
Background:Naming impairment is commonly noted in individuals with aphasia. However, object naming receives more attention than action naming. Furthermore, most studies include participants with aphasia due to only one aetiology, commonly... more
Background:Naming impairment is commonly noted in individuals with aphasia. However, object naming receives more attention than action naming. Furthermore, most studies include participants with aphasia due to only one aetiology, commonly stroke. We developed a new assessment, the Hopkins Action Naming Assessment (HANA), to evaluate action naming impairments.Aims:Our aims were to show that the HANA is a useful tool that can (1) identify action naming impairments and (2) be used to investigate the neural substrates underlying naming. We paired the HANA with the Boston Naming Test (BNT) to compare action and object naming. We considered participants with aphasia due to primary progressive aphasia (PPA) or acute left hemisphere stroke to provide a more comprehensive picture of brain-behaviour relationships critical for naming. Behaviourally, we hypothesised that there would be a double dissociation between object and action naming performance. Neuroanatomically, we hypothesised that different neural substrates would be implicated in object vs. action naming and that different lesion-deficit associations would be identified in participants with PPA vs. acute stroke.Methods & Procedures:Participants (N=138 with PPA, N=37 with acute stroke) completed the BNT and HANA. Behavioural performance was compared. A subset of participants (N=31 with PPA, N=37 with acute stroke) provided neuroimaging data. The whole brain was automatically segmented into regions of interest (ROIs). For participants with PPA, the image variables were the ROI volumes, normalised by the brain volume. For participants with acute stroke, the image variables were the percentage of each ROI affected by the lesion. The relationship between ROIs likely to be involved in naming performance was modelled with LASSO regression.Outcomes & Results:Behavioural results showed a double dissociation in performance: in each group, some participants displayed intact performance relative to healthy controls on actions but not objects and/or significantly better performance on actions than objects, while others showed the opposite pattern. These results support the need to assess both objects and actions when evaluating naming deficits. Neuroimaging results identified different regions associated with object vs. action naming, implicating overlapping but distinct networks of regions. Furthermore, results differed for participants with PPA vs. acute stroke, indicating that critical information may be missed when only one aetiology is considered.Conclusions:Overall, the study provides a more comprehensive picture of the neural bases of naming, underscoring the importance of assessing both objects and actions and considering different aetiologies of damage. It demonstrates the utility of the HANA.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Objective: Test the hypothesis that impairments of rhythm and pitch modulation are associated with listener perception of lack of emotion in speech of patients with right hemisphere stroke (RHS). Background: Impaired expression of... more
Objective: Test the hypothesis that impairments of rhythm and pitch modulation are associated with listener perception of lack of emotion in speech of patients with right hemisphere stroke (RHS). Background: Impaired expression of emotions through prosody (tone of voice, loudness, rate, and rhythm) has been reported after RHS, but acoustic features associated with listener perception of impaired prosody have not been identified. Design/Methods: We tested 49 patients with acute RHS on picture description and sentence repetition with the modeled emotion (sad, happy, surprised, or fearful). Twenty-one controls judged: (1) prosody of picture description on a 7-point scale, and (2) accuracy of patients’ reproducing the speaker’s emotion in repetition of neutral content sentences (as impaired, equivocal, or normal). Acoustic measurements included: coefficient of variation in fundamental frequency (CV Fo; pitch modulation), pitch and loudness range, and assessment of rhythm through Envelop...
Research Interests:
Research Interests:
The communication and behavioral manifestations of primary progressive aphasia (PPA) present ethical and practical challenges for individuals with this clinical syndrome as well as for individuals who are involved closely in their care.... more
The communication and behavioral manifestations of primary progressive aphasia (PPA) present ethical and practical challenges for individuals with this clinical syndrome as well as for individuals who are involved closely in their care. In this article, cases representing all three PPA variants (logopenic variant, nonfluent agrammatic, semantic variant) are presented to illustrate commonly encountered situations in which self-determination is at risk in decisions about housing, driving, social interactions, finances, and treatment interventions. Potential approaches, including patient/family education, implementation of safeguards, redirection to meaningful activities, and protections against vulnerability in treatment decisions, are described to preserve autonomy in patients with this neurodegenerative clinical syndrome.
Research Interests:
Research Interests:
Research Interests: Psychology and Aphasia
Research Interests:
Background: An individual’s diagnostic subtype may fail to predict the efficacy of a given type of treatment for anomia. Classification by conceptual-semantic impairment may be more informative. Aims: This study examined the effects of... more
Background: An individual’s diagnostic subtype may fail to predict the efficacy of a given type of treatment for anomia. Classification by conceptual-semantic impairment may be more informative. Aims: This study examined the effects of conceptual-semantic impairment and diagnostic subtype on anomia treatment effects in primary progressive aphasia (PPA) and Alzheimer’s disease (AD). Methods & Procedures: At baseline, the picture and word versions of the Pyramids and Palm Trees and Kissing and Dancing tests were used to measure conceptual-semantic processing. Based on norming that was conducted with unimpaired older adults, participants were classified as being impaired on both the picture and word versions (i.e., modality-general conceptual-semantic impairment), the picture version (Objects or Actions) only (i.e., visual-conceptual impairment), the word version (Nouns or Verbs) only (i.e., lexical-semantic impairment), or neither the picture nor the word version (i.e., no impairment). Following baseline testing, a lexical treatment and a semantic treatment were administered to all participants. The treatment stimuli consisted of nouns and verbs that were consistently named correctly at baseline (Prophylaxis items) and/or nouns and verbs that were consistently named incorrectly at baseline (Remediation items). Naming accuracy was measured at baseline, and it was measured at three, seven, eleven, fourteen, eighteen, and twenty-one months. Outcomes & Results: Compared to baseline naming performance, lexical and semantic treatments both improved naming accuracy for treated Remediation nouns and verbs. For Prophylaxis items, lexical treatment was effective for both nouns and verbs, and semantic treatment was effective for verbs, but the pattern of results was different for nouns -- the effect of semantic treatment was initially nonsignificant or marginally significant, but it was significant beginning at 11 Months, suggesting that the effects of prophylactic semantic treatment may become more apparent as the disorder progresses. Furthermore, the interaction between baseline Conceptual-Semantic Impairment and the Treatment Condition (Lexical vs. Semantic) was significant for verb Prophylaxis items at 3 and 18 Months, and it was significant for noun Prophylaxis items at 14 and 18 Months. Conclusions: The pattern of results suggested that individuals who have modality-general conceptual-semantic impairment at baseline are more likely to benefit from lexical treatment, while individuals who have unimpaired conceptual-semantic processing at baseline are more likely to benefit from semantic treatment as the disorder progresses. In contrast to conceptual-semantic impairment, diagnostic subtype did not typically predict the treatment effects.
Research Interests:
The sequelae of post-stroke aphasia are considerable, with implications at the societal and personal levels. An understanding of the mechanisms of recovery of cognitive and language processes after stroke and the factors associated with... more
The sequelae of post-stroke aphasia are considerable, with implications at the societal and personal levels. An understanding of the mechanisms of recovery of cognitive and language processes after stroke and the factors associated with increased risk of post-stroke language and cognitive deficits is vital in providing optimal care of individuals with aphasia and in counseling to their families and caregivers. Advances in neuroimaging facilitate the identification of dysfunctional or damaged brain tissue responsible for these cognitive/language deficits and contribute insights regarding the functional neuroanatomy of language. Evidence-based person-centered behavioral therapy remains the mainstay for rehabilitation of aphasia, although emerging evidence shows that neuromodulation is a promising adjunct to traditional therapy. These topics are discussed in this review, illustrating with recent studies from the Stroke Cognitive Outcomes and REcovery (SCORE) lab.
Research Interests:
Research Interests:
Research Interests:
Introduction: Previous studies indicate that anodal transcranial Direct Current Stimulation (A-tDCS) to left hemisphere or cathodal tDCS (C-tDCS) to right hemisphere might augment aphasia therapy to facilitate language recovery after... more
Introduction: Previous studies indicate that anodal transcranial Direct Current Stimulation (A-tDCS) to left hemisphere or cathodal tDCS (C-tDCS) to right hemisphere might augment aphasia therapy to facilitate language recovery after chronic stroke and that cerebellar tDCS can augment verbal fluency and learning in healthy controls. Hypothesis: A-tDCS or C-tDCS) plus naming therapy results in improved naming performance for trained and untrained items from baseline to post-treatment compared to sham plus naming therapy in chronic aphasia. Methods: Six patients with large, chronic left middle cerebral artery (MCA) ischemic stroke and one patient with large bilateral MCA strokes participated in a randomized, double-blind, sham controlled, within-subject crossover trial (15 sessions of sham + naming therapy and 15 sessions of tDCS + naming therapy, in random order, separated by 2 months). 4 patients were randomly assigned to A-tDCS and 3 patients were assigned to C-tDCS. We used 2 mA f...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Lesion-symptom mapping is an important method of identifying networks of brain regions critical for functions. However, results might be influenced substantially by the imaging modality and timing of assessment. We tested the hypothesis... more
Lesion-symptom mapping is an important method of identifying networks of brain regions critical for functions. However, results might be influenced substantially by the imaging modality and timing of assessment. We tested the hypothesis that brain regions found to be associated with acute language deficits depend on (1) timing of behavioral measurement, (2) imaging sequences utilized to define the "lesion" (structural abnormality only or structural plus perfusion abnormality), and (3) power of the study. We studied 191 individuals with acute left hemisphere stroke with MRI and language testing to identify areas critical for spoken word comprehension. We use the data from this study to examine the potential impact of these three variables on lesion-symptom mapping. We found that only the combination of structural and perfusion imaging within 48 h of onset identified areas where more abnormal voxels was associated with more severe acute deficits, after controlling for lesion...
Research Interests:
Research Interests: Psychology, Magnetic Resonance Imaging, Medicine, Speech, Stroke, and 8 moreHumans, Insula, Female, Male, Aged, Middle Aged, Adult, and Cerebral Infarction
The National Institutes of Health Stroke Scale (NIHSS) includes minimal assessment of cognitive function, particularly in right hemisphere (RH) stroke. Descriptions of the Cookie Theft picture from the NIHSS allow analyses that (1)... more
The National Institutes of Health Stroke Scale (NIHSS) includes minimal assessment of cognitive function, particularly in right hemisphere (RH) stroke. Descriptions of the Cookie Theft picture from the NIHSS allow analyses that (1) correlate with aphasia severity and (2) identify communication deficits in RH stroke. We hypothesized that analysis of the picture description contributes valuable information about volume and location of acute stroke. We evaluated 67 patients with acute ischemic stroke (34 left hemisphere [LH]; 33 RH) with the NIHSS, analysis of the Cookie Theft picture, and magnetic resonance imaging, compared with 35 sex- and age-matched controls. We evaluated descriptions for total content units (CU), syllables, ratio of left:right CU, CU/minute, and percent interpretive CU, based on previous studies. Lesion volume and percent damage to regions of interest were measured on diffusion-weighted imaging. Multivariable linear regression identified variables associated with...
Research Interests: Cardiology, Communication Disorders, Aphasia, Magnetic Resonance Imaging, Medicine, and 15 moreHumans, Female, Male, Clinical Sciences, Aged, Middle Aged, Lesion, Neurosciences, Cognition disorders, Functional Laterality, Severity of Illness Index, Neuropsychological Tests, Diffusion magnetic resonance imaging, Cardiovascular medicine and haematology, and cerebral arteries
People with post-stroke aphasia may have some degree of chronic deficit for which current rehabilitative treatments are variably effective. Accumulating evidence suggests that transcranial direct current stimulation (tDCS) may be useful... more
People with post-stroke aphasia may have some degree of chronic deficit for which current rehabilitative treatments are variably effective. Accumulating evidence suggests that transcranial direct current stimulation (tDCS) may be useful for enhancing the effects of behavioral aphasia treatment. However, it remains unclear which brain regions should be stimulated to optimize effects on language recovery. Here, we report on the therapeutic potential of right cerebellar tDCS in augmenting language recovery in SMY, who sustained bilateral MCA infarct resulting in aphasia and anarthria. We investigated the effects of 15 sessions of anodal cerebellar tDCS coupled with spelling therapy using a randomized, double-blind, sham controlled within-subject crossover trial. We also investigated changes in functional connectivity using resting state functional magnetic resonance imaging before and 2 months post-treatment. Both anodal and sham treatments resulted in improved spelling to dictation fo...
Research Interests:
Research Interests:
An inflated cuff, although commonly thought to be required for the ventilator-dependent patient with a tracheostomy cannula, precludes speaking and has adverse implications for swallowing. Clinical trials with five ventilator-dependent,... more
An inflated cuff, although commonly thought to be required for the ventilator-dependent patient with a tracheostomy cannula, precludes speaking and has adverse implications for swallowing. Clinical trials with five ventilator-dependent, cognitively intact individuals with glottic control document that a deflated cuff is compatible with ventilation, preserves oral communication, and restores safe alimentation by mouth.