Which neuropsychiatric and behavioural features distinguish frontal and temporal variants of frontotemporal dementia from Alzheimer's disease?

OBJECTIVES: To investigate the prevalence of changes in mood, personality, and behaviour in frontotemporal dementia (FTD) and Alzheimer's disease (AD) and hence, which features reliably distinguish between them. To establish whether the frontal and temporal variants of FTD are characterised by different behavioural changes. METHODS: A questionnaire was designed to assess a wide range of neuropsychiatric changes; it incorporated features reported in previous studies of FTD and components of the neuropsychiatric inventory.(1) This was completed by 37 carers of patients with Alzheimer's disease (AD) and 33 patients with frontotemporal dementia (FTD), comprising 20 with temporal variant FTD (tv FTD) or semantic dementia and 13 with frontal variant FTD (fv FTD). An exploratory principal components factor analysis and discriminant function analysis was applied. RESULTS: Factor analysis showed four robust and meaningful symptom clusters: factor 1-stereotypic and eating behaviour; factor 2-executive dysfunction and self care; factor 3-mood changes; factor 4-loss of social awareness. Only stereotypic and altered eating behaviour and loss of social awareness reliably differentiated AD from FTD with no effect of disease severity. By contrast, executive dysfunction, poor self care, and restlessness showed a significant effect of disease severity only, with the more impaired patients scoring more highly. Changes in mood were found to be equally prevalent in the three patient groups. Analysis of individual symptoms showed increased rates of mental rigidity and depression in the patients with semantic dementia compared with those with fv FTD. Conversely, the latter group showed greater disinhibition. Discriminant function analysis correctly classified 71.4% overall and 86.5% of the patients with AD. CONCLUSIONS: This questionnaire disclosed striking differences between patients with FTD and AD, but only stereotypic behaviour, changes in eating preference, disinhibition, and features of poor social awareness reliably separated the groups. The patients with fv FTD and semantic dementia were behaviourally very similar, reflecting the involvement of a common network, the ventral frontal lobe, temporal pole, and amygdala. Dysexecutive symptoms and poor self care were found to be affected by the severity of the disease, reflecting perhaps spread to dorsolateral prefrontal areas relatively late in the course of both FTD and AD. This questionnaire may be of value in the diagnosis and the monitoring of therapies.     

Novel applications of social-personality measures to the study of dementia

Despite the realization that personality change is a core feature of frontotemporal dementia (FTD), little work has been performed using personality as a diagnostic tool for this disease. Likewise, personality change in Alzheimer's disease (AD) has long been recognized, but generally has not been used for diagnostic purposes. We introduce novel social-personality measures (Big Five Inventory, Interpersonal Adjectives Scale and Interpersonal Measure of Psychopathy) in the differential diagnosis of AD and temporal subtypes of FTD, and integrate these measures with traditional behavioural and neuropsychological methods commonly used in diagnosing dementia. We present four cases: an FTD patient with predominantly left temporal degeneration, an FTD patient with predominantly right temporal degeneration and two patients with Alzheimer's disease (one with mild and the other with moderate impairment). Results show the diagnostic utility of these measures in differentiating among temporal subtypes of FTD and moderate AD. Right temporal FTD, in particular, shows profound shifts in personality and interpersonal behaviour, as well as a striking lack of insight into these shifts. In addition to diagnostic purposes, we discuss how measures of personality and interpersonal behaviour can be utilized as an important component of understanding disease susceptibility and risk, as well as offering insights into the neuroanatomical underpinnings of personality and social behaviour.     

Frontotemporal dementia: patient characteristics,cognition, and behaviour

OBJECTIVES: To describe sociodemographic data of patients with frontotemporal dementia (FTD), to compare the cognitive profile of patients with FTD with that of severity-matched patients with Alzheimer's disease using the CERAD neuropsychological battery (CERAD-NP), to investigate the frequency of behavioural disturbances, and to examine the relation between FTD-specific non-cognitive behavioural symptoms of patients with FTD with age and sex. METHODS: Fifty outpatients were diagnosed with FTD according to the Lund-Manchester consensus criteria. Cognitive impairment was assessed in 30 patients using the CERAD-NP. Severity of dementia was rated on the Clinical Dementia Rating (CDR). Eleven non-cognitive symptoms were rated by severity. To compare CERAD-NP results between patients with FTD and AD, 30 patients with AD were matched for age, sex, and global severity of cognitive performance. RESULTS: The average age at onset of first symptoms was 57.8 years. Eighteen patients (36%) had a positive family history of dementia. On the CERAD-NP patients with FTD performed significantly better than patients with AD on word list learning, delayed verbal recall and visuoconstruction (p < 0.05). There were no significant differences between FTD and AD on naming and verbal fluency tasks. The most frequent non-cognitive behavioural symptoms in FTD were loss of insight, speech abnormality, and apathy. Non-cognitive behavioural symptoms were more frequent in younger and in male than in older patients and in female patients. CONCLUSIONS: The CERAD-NP is a valuable clinical instrument for the cognitive evaluation of patients with suspected FTD. Complementary short tests of attention and executive function may be recommended. To enhance diagnostic sensitivity informant interviews should focus on non-cognitive behavioural changes, taking advantage of standardised questionnaires.     

Changes in dietary or eating behavior in frontotemporal dementia versus Alzheimer's disease

BACKGROUND: Changes in dietary or eating behavior are common in dementia and may help distinguish between different dementing illnesses. Objective: To evaluate and characterize differences in dietary and eating behavior among patients with early frontotemporal dementia (FTD) versus Alzheimer's disease (AD). METHODS: This study administered the Food-Related Problems Questionnaire (FRPQ) to caregivers of 16 patients with FTD and 16 comparable patients with AD. The FRPQ was evaluated at initial presentation when patients presented for a diagnostic evaluation. RESULTS: Compared with the AD patients, the FTD patients had significantly more changes on the FRPQ. Subscale analysis indicated that the FTD patients showed impairment of observed satiety, improper taking of food, and inappropriate responses when food was not available. CONCLUSIONS: The use of food-related questionnaires, such as the FRPQ, can help distinguish FTD patients, early in their course, from those with AD and can further characterize the altered dietary and eating behavior.     

Ventromedial‐frontopolar prefrontal cortex atrophy correlates with insight loss in frontotemporal dementia and Alzheimer's disease

Loss in insight is a major feature of frontotemporal dementia (FTD) but has been investigated relatively little. More importantly, the neural basis of insight loss is still poorly understood. The current study investigated insight deficit profiles across a large cohort of neurodegenerative patients (n = 81), including FTD and Alzheimer's disease (AD) patients. We employed a novel insight questionnaire, which tapped into changes across different domains: social interaction, emotion, diagnosis/treatment, language, and motivation. FTD subtypes varied considerably for insight loss, with the behavioral variant worst and the progressive non‐fluent variant least affected. All other subtypes and AD showed milder but consistent insight loss. Voxel‐based morphometry analysis revealed that overall insight loss correlated with ventromedial and frontopolar prefrontal atrophy, with exception of social interaction and emotion insight loss, which additionally correlated with lateral temporal and amygdala atrophy, respectively. Our results show that patients with neurodegenerative conditions show variable loss of insight, with ventromedial and frontopolar cortex regions appearing to be particularly important for insight. Hum Brain Mapp 35:616–626, 2014. © 2012 Wiley Periodicals, Inc.     

Behaviour in frontotemporal dementia, Alzheimer's disease and vascular dementia

OBJECTIVES: The study aimed to increase understanding of behavioural changes in frontotemporal dementia (FTD) and identify features that best differentiate FTD from Alzheimer's disease (AD) and cerebrovascular dementia (CvD). METHODS: A semi-structured questionnaire was administered to carers of 30 FTD, 75 AD and 34 CvD patients. RESULTS: Behavioural changes that strongly discriminated FTD from AD and to a lesser extent CvD were loss of emotions and insight, selfishness, disinhibition, personal neglect, gluttony and sweet food preference, wandering, motor and verbal stereotypies, loss of pain, echolalia and mutism. Irritability, hyposexuality and hypersomnia did not discriminate. Emotional, eating and stereotyped behaviours correctly classified 95% of patients using regression analysis. CONCLUSIONS: Behavioural characteristics accurately differentiate FTD from AD and CvD. The findings highlight the particular importance of affective change in FTD, and underline the role of the frontotemporal lobes in emotion.     

Social mind representation: where does it fail in frontotemporal dementia?

We aimed at investigating social disability and its cerebral correlates in frontotemporal dementia (FTD). To do so, we contrasted answers of patients with early-stage FTD and of their relatives on personality trait judgment and on behavior prediction in social and emotional situations. Such contrasts were compared to control contrasts calculated with answers of matched controls tested with their relatives. In addition, brain metabolism was measured in patients with positron emission tomography and the [(18)F]fluorodeoxyglucose method. Patients turned out to be as accurate as controls in describing their relative's personality, but they failed to predict their relative's behavior in social and emotional circumstances. Concerning the self, patients were impaired both in current personality assessment and in prediction of their own behavior. Those two self-evaluation measures did not correlate. Only patients' anosognosia for social behavioral disability was found to be related to decreased metabolic activity in the left temporal pole. Such results suggest that anosognosia for social disability in FTD originates in impaired processing of emotional autobiographical information, leading to a self-representation that does not match current behavior. Moreover, we propose that perspective-taking disability participates in anosognosia, preventing patients from correcting their inaccurate self-representation based on their relative's perspective.     

Evaluation of the NINCDS-ADRDA criteria in the differentiation of Alzheimer's disease and frontotemporal dementia

OBJECTIVES: The diagnosis of Alzheimer's disease (AD) is now reliant on the use of NINCDS-ADRDA criteria. Other diseases causing dementia are being increasingly recognised--for example, frontotemporal dementia (FTD). Historically, these disorders have not been clearly demarcated from AD. This study assesses the capability of the NINCDS-ADRDA criteria to accurately distinguish AD from FTD in a series of pathologically proved cases. METHODS: The case records of 56 patients (30 with AD, 26 with FTD) who had undergone neuropsychological evaluation, brain imaging, and ultimately postmortem, were assessed in terms of whether at initial diagnosis the NINCDS-ADRDA criteria were successful in diagnosing those patients who had AD and excluding those who did not. RESULTS: (1) The overall sensitivity of the NINCDS-ADRDA criteria in diagnosing "probable" AD from 56 patients with cortical dementia (AD and FTD) was 0.93. However, the specificity was only 0.23; most patients with FTD also fulfilled NINCDS-ADRDA criteria for AD. (2) Cognitive deficits in the realms of orientation and praxis significantly increased the odds of a patient having AD compared with FTD, whereas deficits in problem solving significantly decreased the odds. Neuropsychological impairments in the domains of attention, language, perception, and memory as defined in the NINCDS-ADRDA statement did not contribute to the clinical differentiation of AD and FTD. CONCLUSION: NINCDS-ADRDA criteria fail accurately to differentiate AD from FTD. Suggestions to improve the diagnostic specificity of the current criteria are made.     

Memory impairment differs in frontotemporal dementia and Alzheimer's disease

The aim of this study was to assess short-term and long-term explicit memory and implicit memory in frontotemporal dementia (FTD; frontal variant) and to compare FTD and Alzheimer's disease (AD) patients with similar severity of dementia. Fifteen FTD patients [mean age: 68 years; Mini-Mental State (MMS): 24], 30 probable AD patients (mean age: 72 years; MMS: 23) and 12 healthy subjects participated in the study. The three groups were comparable in terms of gender and educational level. Short-term memory was assessed with the digit span and Corsi block-tapping tests. Explicit verbal memory was assessed with the Grober and Buschke test, and implicit memory with a verbal priming task and a fragmented picture test. FTD patients demonstrated a genuine memory deficit with impaired digit span, encoding deficit and retrieval strategy difficulties, but preserved implicit verbal and visual priming. Memory patterns differed in AD and FTD: short-term memory and free recall were similarly decreased in FTD and AD but cues provided more benefit to FTD than to AD; encoding was more impaired and the forgetting rate was faster in AD than in FTD; priming was lower in AD than in FTD. AD patients with clinical and imaging frontal lobe dysfunction tended to have lower memory performance and to differ even more from FTD patients than AD patients without frontal lobe dysfunction.     

Determinants of quality of life in young onset dementia – results from a European multicenter assessment

ABSTRACT

Background: Promoting adaptation, improving well-being and maintaining an optimal quality of life (QOL) is an important aspect in dementia care. The purpose of this study was to identify determinants of QOL in young onset dementia, and to assess differences in QoL domains between people with Alzheimer's disease (AD) and frontotemporal dementia (FTD).

Methods: In total 135 persons with AD and 58 persons with FTD were included from two prospective cohort studies. QOL was assessed with the proxy reported quality of life in Alzheimer's disease questionnaire (QoL-AD). Possible determinants were explored using multiple linear regression and included sociodemographic variables, diagnosis, dementia severity, disease awareness, neuropsychiatric symptoms, met and unmet needs and hours of personal and instrumental care. Differences between QOL domains in people with AD and FTD were calculated using Mann-Whitney U tests.

Results: Lower QOL was associated with more depressive symptoms, lower disease awareness, and a higher amount of needs, both met and unmet. People with AD scored lower on the memory and higher on the friends' subscale. No differences were found for the other items.

Conclusion: This study demonstrates a unique set of determinants of QOL in AD and FTD. Interventions directed towards these specific factors may improve QOL.     

Metacognitive deficits in frontotemporal dementia

OBJECTIVES: To investigate whether metacognitive impairments in self-awareness and self-monitoring occur in patients with frontotemporal dementia (FTD), particularly among those with prominent social and dysexecutive impairments. METHODS: Patients diagnosed with FTD were divided by clinical subtype (social-dysexecutive (n = 12) aphasic (n = 15), and constituent subgroups of progressive non-fluent aphasia and semantic dementia) and compared with subjects with probable Alzheimer's disease (AD, n = 11) and age-matched healthy controls (n = 11). All subjects completed comprehensive behavioural ratings scales, which were compared with caregiver ratings. Subjects also rated their test performances in verbal associative fluency, word list learning, and memory task with comparisons made between actual and judged performance levels. RESULTS: The FTD sample as a whole showed significantly less behavioural self-awareness and self-knowledge than the AD and healthy control samples. FTD patients with prominent social and dysexecutive impairments demonstrated the most extensive loss of self-awareness and self-knowledge, significantly overrating themselves in multiple social, emotional, and cognitive domains, and failing to acknowledge that any behavioural change had occurred in most areas. The remaining clinical samples showed select and minimal discrepancies. All clinical groups were significantly unaware of their apathy levels. Most FTD patients judged episodic cognitive test performance adequately, with partial difficulties observed in the socially impaired and progressive non-fluent aphasia subgroups. CONCLUSIONS: FTD patients, particularly those with prominent social and dysexecutive impairments, exhibit profound metacognitive anosognosia that may represent a loss of self-awareness, self-monitoring, and self-knowledge, likely related to significant prefrontal pathophysiology. Other FTD clinical groups and AD patients showed less pervasive and more select metacognitive deficiencies.     

An investigation of moral judgement in frontotemporal dementia.

OBJECTIVE: To investigate the basis of disturbed moral judgment in patients with frontotemporal dementia (FTD). BACKGROUND: FTD is characterized by difficulty in modulating social behavior. Patients lack social propriety and may perform sociopathic acts. In addition, FTD patients often lack empathy for others. These findings suggest alterations in the nature of morality in patients with FTD. METHOD: We administered an inventory of moral knowledge and two moral dilemmas to 26 patients with the frontal variant of FTD, 26 patients with Alzheimer disease (AD), and 26 normal control subjects. The FTD patients met Consensus Criteria for FTD and had corroborative frontal abnormalities on functional neuroimaging. The FTD and AD patients were comparably impaired on dementia measures. RESULTS: All these groups showed the retention of knowledge for moral behavior and the ability to make "impersonal" moral judgments. In contrast, the FTD patients were impaired in their ability to make immediate, emotionally based moral judgments compared with the patients with AD and the normal control subjects. CONCLUSIONS: These findings are consistent with an attenuation of the automatic emotional identification with others that is part of the innate moral sense. Such a disturbance may result from neurodegenerative disease affecting the ventromedial frontal cortex.     

Rates of global and regional cerebral atrophy in AD and frontotemporal dementia.

OBJECTIVE: Serial registered MRI provides a reproducible technique for detecting progressive cerebral atrophy in vivo and was used to determine if there were differences between the rates of cerebral atrophy in AD and frontotemporal dementia (FTD). METHODS: Eighty-four patients with dementia (54 AD and 30 FTD) and 27 age-matched control subjects each had at least two volumetric MR scans. Serial scans were positionally matched (registered), and brain volume loss was determined by calculation of the brain boundary shift integral. RESULTS: There was a difference between the rates of whole-brain atrophy in patients (mean annual volume loss 2.7% of total brain volume) and in control subjects (mean annual volume loss 0.5%). AD and FTD were associated with different rates of atrophy (mean annual losses 2.4 and 3.2%). The range of atrophy rates in the FTD group (0.3 to 8.0%) greatly exceeded that in the AD group (0.5 to 4.7%). Frontal-variant FTD was associated with a wider range of atrophy rates than temporal-variant FTD. Analysis of regional brain atrophy rates revealed that there was widespread symmetrically distributed cerebral volume loss in AD, whereas in frontal FTD there was greater atrophy anteriorly and in temporal FTD the atrophy rate was greatest in the left anterior cerebral cortex. CONCLUSIONS: Both AD and FTD patients had increased rates of brain atrophy. Whereas the patients with AD were associated with a relatively restricted spread of atrophy rates, the greater spread of rates observed in the patients with FTD may reflect the heterogeneity of disease in FTD, with differences observed between frontal and temporal FTD. Increased rates of whole-brain atrophy did not discriminate AD from FTD, but analysis of regional atrophy rates revealed marked differences between patient groups.     

Does the pattern of atrophy of the Corpus callosum differ between patients with frontotemporal dementia and patients with Alzheimer's disease?

The pattern of callosal atrophy might be useful for the differentiation between frontotemporal dementia (FTD) and Alzheimer's disease (AD) in advanced cases. However, it is unclear whether the pattern of callosal atrophy differs between patients with FTD and patients with AD in mild to moderate stages. Volumetric MR images were recorded from 48 probands (12 with FTD, 12 with late-onset AD, and 24 controls). All patients were in a mild or in a moderate stage. The corpus callosum was divided into five segments. A repeated-measures analysis of variance showed that there was no difference in the pattern of callosal atrophy between the groups. We provide evidence that patients with FTD and patients with late-onset AD do not differ in the pattern of callosal atrophy on condition that: (1) FTD patients and AD patients are in a mild to moderate stage and (2) FTD patients and AD patients differ in age.     

Differential circadian rhythm disturbances in men with Alzheimer disease and frontotemporal degeneration

BACKGROUND: Caregiver exhaustion is a frequent consequence of sleep disturbance and rest-activity rhythm disruption that occurs in dementia. This exhaustion is the causal factor most frequently cited by caregivers in making the decision to institutionalize patients with dementia. Recent studies have implicated dysfunction of the circadian pacemaker in the etiology of these disturbances in dementia. METHODS: We studied the activity and core-body temperature rhythms in a cohort of 38 male patients with a clinical diagnosis of probable Alzheimer disease (AD) approximately 2 years before death. These patients were later given a confirmed diagnosis of AD (n = 23), frontotemporal degeneration (FTD) (n = 9), or diffuse Lewy body disease (DLB) with mixed AD or FTD pathologies (n = 6) after autopsy and neuropathological examination. Physiological rhythms of patients with AD and FTD were then compared with a group of normal, elderly men (n = 8) from the community. RESULTS: Alzheimer patients showed increased nocturnal activity and a significant phase-delay in their rhythms of core-body temperature and activity compared with patients with FTD and controls. The activity rhythm of FTD patients was highly fragmented and phase-advanced in comparison with controls and apparently uncoupled from the rhythm of core-body temperature. CONCLUSIONS: Patients with AD and patients with FTD show different disturbances in their rhythms of activity and temperature compared with each other and with normal elderly patients.     

Discriminant validity and neuroanatomical correlates of rule monitoring in frontotemporal dementia and Alzheimer's disease

Despite the predominant frontal neuropathology of frontotemporal dementia (FTD), traditional measures of executive functioning do not reliably distinguish FTD from Alzheimer's disease (AD). Performance monitoring is an executive function that is associated with frontal lobe integrity and may be disrupted in FTD. The current study adopted a component process approach to evaluate the discriminant validity and neuroanatomical correlates of performance monitoring (i.e., rule monitoring) during an executive spatial planning task. Forty-four participants with FTD, 30 with AD, and 27 healthy comparison (HC) subjects completed the Delis-Kaplan Executive Function System (D-KEFS) Tower task. A subset of patients underwent structural magnetic resonance imaging to obtain regional measures of cortical volumes. FTD and AD groups demonstrated significantly poorer overall achievement scores on the Tower test relative to the HC sample, but did not differ from one another. In contrast, the FTD group committed significantly more rule violation errors than both HC and AD groups, indicating poorer performance monitoring. In addition, poorer overall achievement correlated with smaller brain volumes in several regions, including bilateral frontal and parietal regions, whereas an increased number of rule violations correlated specifically with decreased bilateral frontal volume. Both left and right frontal volumes remained significant predictors of rule violation errors after controlling for the contribution of overall achievement on the task and all other brain regions. Findings are consistent with literature implicating the frontal lobes in performance monitoring and highlight the importance of characterizing the component processes of performance failures in the cognitive assessment of FTD and AD.     

Frontal assessment battery and differential diagnosis of frontotemporal dementia and Alzheimer disease

BACKGROUND: The different distribution of pathologic features in frontotemporal dementia (FTD) and Alzheimer disease (AD) predicts a predominant dysexecutive syndrome in FTD. The Frontal Assessment Battery (FAB) has previously been validated in diseases associated with a frontal lobe dysfunction. OBJECTIVE: To evaluate the sensitivity of the FAB to differentiate FTD and AD. DESIGN: Comparison study. SETTING: Memory Clinic of the Salpêtrière Hospital, Paris, France. PATIENTS: Twenty-six patients with FTD and 64 patients with AD. MAIN OUTCOME MEASURES: Comparison of FAB and Mini-Mental State Examination (MMSE) scores between patients with FTD and those with AD. RESULTS: The mean +/- SD FAB scores significantly differed between patients with FTD (7.6 +/- 4.2) and those with AD (12.6 +/- 3.7) (P<.001), but not MMSE scores. The FAB correctly identified 78.9% of the patients. These results were maintained in a subgroup of mildly demented patients (MMSE score, > or =24). In these patients, a cutoff score of 12 on the FAB was optimal to differentiate both disorders (sensitivity, 77%; specificity, 87%). CONCLUSIONS: The FAB takes less than 10 minutes to administer and provides an objective measure to distinguish FTD from AD in mildly demented patients.     

Disrupted sleep and circadian patterns in frontotemporal dementia

Background:  A study of the pattern of Sleep/Wake disturbance in frontotemporal dementia (FTD).
Methods:  Sleep diaries and prolonged actigraphy were used to record the activity, sleep and wake of 13 patients with a clinical diagnosis of FTD. These were compared with diaries and actigraphy from normal age/sex matched controls and also to a population with probable Alzheimer's disease (AD).
Results:  There was significant sleep/wake disturbance in FTD. This occurred throughout the course of the illness and the nature of the sleep disturbance was different to patients with AD. FTD subjects showed increased nocturnal activity and decreased morning activity compared with controls, suggesting possible phase delay. Sleep diary data confirmed decreased sleep efficiency and decreased total sleep in all FTD patients.
Conclusions:  We describe significant sleep disturbance in non-institutionalized patients with FTD and suggest that early sleep disturbance may help differentiate between FTD and AD.     

Neuroanatomy of the self: evidence from patients with frontotemporal dementia

OBJECTIVE: To evaluate the frequency and types of change in "self" seen in frontotemporal dementia (FTD) and to determine the relative involvement of the nondominant and dominant frontal and temporal brain regions in FTD patients with or without changes in a sense of self using neuropsychology tests and neuroimaging. BACKGROUND: The self has been defined as "the total, essential, or particular being of a person" involving "the essential qualities distinguishing one person from another." Some suggest that the frontal lobes play a dominant role in maintaining the self. FTD affects anterior frontal and temporal areas and can be associated with a loss of self. METHODS: Seventy-two consecutive FTD patients were evaluated with neuropsychiatric, neuropsychologic, and behavioral measures. Patients were imaged with MRI and SPECT. Charts were reviewed by a social psychologist to determine patients who exhibited a dramatic change in their self as defined by changes in political, social, or religious values. The brain areas with the most severe atrophy or hypoperfusion on neuroimaging were noted. RESULTS: Seven of 72 patients exhibited a dramatic change in self. In six of the seven, the selective dysfunction involved the nondominant frontal region. In contrast, only one of the other 65 patients without selective nondominant frontal dysfunction showed a change in self. CONCLUSIONS: FTD patients with asymmetric loss of function in the nondominant frontal lobe often exhibit a diminished maintenance of previously learned self-concepts despite intact memory and language. Normal nondominant frontal function is important for the maintenance of the self.