Impaired Emotion Recognition: A Potential Marker for Social Behavioral Problems in Patients With Amnestic Mild Cognitive Impairment and Early Alzheimer Disease?

OBJECTIVE

Emotion recognition, an important aspect of social cognition, can be impaired already in early Alzheimer disease dementia and amnestic mild cognitive impairment (aMCI) and may underly social behavioral changes, which can increase caregiver burden. However, social behavior is difficult to assess in outpatient settings. We evaluated whether impaired emotion recognition is related to proxy-rated social behavioral problems and thus can serve as a marker of these changes.

PATIENTS AND METHOD

Emotion recognition was assessed with Ekman 60 Faces Test (EFT-total, 6 separate emotions) in patients (n = 31 AD; n = 37 aMCI) and healthy controls (n = 60 HCs). Social behavioral problems were rated by proxies with the neuropsychiatric inventory (agitation, apathy, irritability, disinhibition, and a sum score). It tested whether EFT scores differed between patients with and without behavioral problems.

RESULTS

AD had worse EFT-total ( P <0.001), disgust ( P = 0.02), and fear ( P = 0.001) than HC, but not than aMCI, who did not differ from HC. AD displayed more disinhibition ( P < 0.05). EFT and neuropsychiatric inventory sum scores were not significantly correlated. Patients with apathy had lower EFT-total ( P = 0.02).

CONCLUSIONS

Measuring emotion recognition adds value: it is impaired in early neurodegeneration and associated with apathy but not necessarily related to overall changes in social behavior in this population.

Clinical relevance of the radiation dose bath in lower grade glioma, a cross-sectional pilot study on neurocognitive and radiological outcome

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Radiation-induced brain damage as a consequence of the RT dose bath was investigated.

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Multiple MRI-derived metrics and neurocognitive function domains were analysed.

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Our novel approach accounted for confounding effects associated with lower grade glioma.

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Higher RT dose to the left cerebrum was associated with poorer verbal memory performance.

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Higher RT dose correlated with hippocampal volume.

Aim

To investigate the clinical relevance of the radiotherapy (RT) dose bath in patients treated for lower grade glioma (LGG).

Methods

Patients (n = 17) treated with RT for LGG were assessed with neurocognitive function (NCF) tests and structural Magnetic Resonance Imaging (MRI) and categorized in subgroups based on tumour lateralisation. RT dose, volumetric results and cerebral microbleed (CMB) number were extracted for contralateral cerebrum, contralateral hippocampus, and cerebellum. The RT clinical target volume (CTV) was included in the analysis as a surrogate for focal tumour and other treatment effects. The relationships between RT dose, CTV, NCF and radiological outcome were analysed per subgroup.

Results

The subgroup with left-sided tumours (n = 10) performed significantly lower on verbal tests. The RT dose to the right cerebrum, as well as CTV, were related to poorer performance on tests for processing speed, attention, and visuospatial abilities, and more CMB.

In the subgroup with right-sided tumours (n = 7), RT dose in the left cerebrum was related to lower verbal memory performance, (immediate and delayed recall, r = −0.821, p = 0.023 and r = −0.937, p = 0.002, respectively), and RT dose to the left hippocampus was related to hippocampal volume (r = −0.857, p = 0.014), without correlation between CTV and NCF.

Conclusion

By using a novel approach, we were able to investigate the clinical relevance of the RT dose bath in patients with LGG more specifically. We used combined MRI-derived and NCF outcome measures to assess radiation-induced brain damage, and observed potential RT effects on the left-sided brain resulting in lower verbal memory performance and hippocampus volume.

Serendipitous Stimulation of Nucleus Basalis of Meynert-The Effect of Unintentional, Long-Term High-Frequency Stimulation on Cognition in Parkinson's Disease

There is a growing interest in deep brain stimulation (DBS) of the nucleus basalis of Meynert (NBM) as a potential therapeutic modality for Parkinson’s disease dementia (PDD). Low-frequency stimulation has yielded encouraging results in individual patients; however, these are not yet sustained in larger studies. With the aim to expand the understanding of NBM-DBS, we share our experience with serendipitous NBM-DBS in patients treated with DBS of the internal Globus pallidus (GPi) for Parkinson’s disease. Since NBM is anatomically located ventral to GPi, several GPi-treated patients appeared to have the distal contact of DBS-electrode(s) positioned in the NBM. We hypothesized that unintentional high-frequency NBM-DBS over a period of one year would result in the opposite effect of low-frequency NBM-stimulation and cause cognitive decline. We studied a cohort of 33 patients with bilateral high-frequency DBS in the GPi for Parkinson’s disease, of which twelve were unintentionally co-stimulated in NBM. The subgroups of unintentional unilateral (N = 7) and bilateral NBM-DBS (N = 5) were compared to the control group of bilateral GPi-DBS (N = 11). Here, we show that unintentional high-frequency NBM-DBS did not cause a significantly faster decline in cognitive function. Further research is warranted for characterizing the therapeutic role of NBM-DBS.

Cognitive Impairment in Long-Term Survivors of Testicular Cancer More Than 20 Years after Treatment

BACKGROUND

Impaired cognition can be a late effect after treatment in long-term testicular cancer (TC) survivors, negatively affecting their daily life. However, little data is available beyond 20 years post-treatment. We assessed cognitive impairment in very long-term TC survivors after CT or RT and compared the results with stage I TC survivors and controls.

METHODS

In this cross-sectional multicenter cohort study, we enrolled TC survivors (treated with orchiectomy followed by CT or RT or orchiectomy only)-with a follow-up duration ≥ 20 years-and age-matched healthy controls. Cognitive testing included the Auditory Verbal Learning Test, Letter Fluency Test, Category Fluency Test, and Trail Making Test. We used fasting blood samples to assess the presence of hypogonadism and measured cardiovascular aging parameters, including carotid pulse wave velocity (c-PWV) and advanced glycation end products (AGEs).

RESULTS

We included 184 TC survivors (66 CT patients, 53 RT patients, and 65 orchiectomy-only patients) and 70 healthy controls. The median follow-up was 26 years (range: 20-42). TC survivors had a lower combined score of the cognitive tests (mean cumulative Z-score -0.85; 95% CI -1.39 to -0.33) compared to controls (mean 0.67; 95% CI -0.21 to 1.57, p < 0.01). In univariate analysis, the presence of hypogonadism (β -1.50, p < 0.01), high c-PWV (β -0.35, p = 0.09), and high AGEs (β -1.27, p = 0.02) were associated with lower cognitive scores, while only AGEs (β -1.17, p = 0.03) remained a significant predictor in multivariate analysis (Model R2 0.31, p < 0.01).

CONCLUSIONS

Long-term TC survivors performed worse on cognitive tests compared to controls. Physicians and patients should be informed about timely cardiovascular risk management and testosterone supplementation therapy during follow-up to reduce the risk of cognitive impairment.

TRIAL REGISTRATION

NCT02572934.

The neural underpinnings of facial emotion recognition in ischemic stroke patients

Deficits in facial emotion recognition occur frequently after stroke, with adverse social and behavioural consequences. The aim of this study was to investigate the neural underpinnings of the recognition of emotional expressions, in particular of the distinct basic emotions (anger, disgust, fear, happiness, sadness and surprise). A group of 110 ischaemic stroke patients with lesions in (sub)cortical areas of the cerebrum was included. Emotion recognition was assessed with the Ekman 60 Faces Test of the FEEST. Patient data were compared to data of 162 matched healthy controls (HC's). For the patients, whole brain voxel-based lesion-symptom mapping (VLSM) on 3-Tesla MRI images was performed. Results showed that patients performed significantly worse than HC's on both overall recognition of emotions, and specifically of disgust, fear, sadness and surprise. VLSM showed significant lesion-symptom associations for FEEST total in the right fronto-temporal region. Additionally, VLSM for the distinct emotions showed, apart from overlapping brain regions (insula, putamen and Rolandic operculum), also regions related to specific emotions. These were: middle and superior temporal gyrus (anger); caudate nucleus (disgust); superior corona radiate white matter tract, superior longitudinal fasciculus and middle frontal gyrus (happiness) and inferior frontal gyrus (sadness). Our findings help in understanding how lesions in specific brain regions can selectively affect the recognition of the basic emotions.

Comparing static and dynamic emotion recognition tests: Performance of healthy participants

Facial expressions have a communicatory function and the ability to read them is a prerequisite for understanding feelings and thoughts of other individuals. Impairments in recognition of facial emotional expressions are frequently found in patients with neurological conditions (e.g. stroke, traumatic brain injury, frontotemporal dementia). Hence, a standard neuropsychological assessment should include measurement of emotion recognition. However, there is debate regarding which tests are most suitable. The current study evaluates and compares three different emotion recognition tests. 84 healthy participants were included and assessed with three tests, in varying order: a. Ekman 60 Faces Test (FEEST) b. Emotion Recognition Task (ERT) c. Emotion Evaluation Test (EET). The tests differ in type of stimuli from static photographs (FEEST) to more dynamic stimuli in the form of morphed photographs (ERT) to videos (EET). Comparing performances on the three tests, the lowest total scores (67.3% correct answers) were found for the ERT. Significant, but moderate correlations were found between the total scores of the three tests, but nearly all correlations between the same emotions across different tests were not significant. Furthermore, we found cross-over effects of the FEEST and EET to the ERT; participants attained higher total scores on the ERT when another emotion recognition test had been administered beforehand. Moreover, the ERT proved to be sensitive to the effects of age and education. The present findings indicate that despite some overlap, each emotion recognition test measures a unique part of the construct. The ERT seemed to be the most difficult test: performances were lowest and influenced by differences in age and education and it was the only test that showed a learning effect after practice with other tests. This highlights the importance of appropriate norms.

Driving Performance in Patients With Idiopathic Cervical Dystonia; A Driving Simulator Pilot Study

Objective: To explore driving performance and driving safety in patients with cervical dystonia (CD) on a simulated lane tracking, intersections and highway ride and to compare it to healthy controls.

Design: This study was performed as an explorative between groups comparison.

Participants: Ten CD patients with idiopathic CD, 30 years or older, stable on botulinum toxin treatment for over a year, holding a valid driver's license and being an active driver were compared with 10 healthy controls, matched for age and gender.

Main outcome measures: Driving performance and safety, measured by various outcomes from the simulator, such as the standard deviation of the lateral position on the road, rule violations, percentage of line crossings, gap distance, and number of collisions. Fatigue and driving effort were measured with the Borg CR-10 scale and self-perceived fitness to drive was assessed with Fitness to Drive Screening.

Results: Except for a higher percentage of line crossings on the right side of the road by controls (median percentage 2.30, range 0.00–37.00 vs. 0.00, range 0.00–9.20, p = 0.043), no differences were found in driving performance and driving safety during the simulator rides. Fatigue levels were significantly higher in CD patients just before (p = 0.005) and after (p = 0.033) the lane tracking ride (patients median fatigue levels before 1.5 (range 0.00–6.00) and after 1.5 (range 0.00–7.00) vs. controls median fatigue levels before and after 0.00 (no range). No significant differences were found on self-perceived fitness to drive.

Conclusion: In patients with CD there were no indications that driving performance or driving safety were significant different from healthy controls in a simulator. Patients reported higher levels of fatigue both before and after driving compared to controls in accordance with the non-motor symptoms known in CD.

Crossed Cerebellar Diaschisis in Alzheimer's Disease

BACKGROUND

We describe the phenomenon of crossed cerebellar diaschisis (CCD) in four subjects diagnosed with Alzheimer's disease (AD) according to the National Institute on Aging - Alzheimer Association (NIA-AA) criteria, in combination with 18F-FDG PET and 11C-PiB PET imaging.

METHODS

18F-FDG PET showed a pattern of cerebral metabolism with relative decrease most prominent in the frontal-parietal cortex of the left hemisphere and crossed hypometabolism of the right cerebellum. 11C-PiB PET showed symmetrical amyloid accumulation, but a lower relative tracer delivery (a surrogate of relative cerebral blood flow) in the left hemisphere. CCD is the phenomenon of unilateral cerebellar hypometabolism as a remote effect of supratentorial dysfunction of the brain in the contralateral hemisphere. The mechanism implies the involvement of the cortico-ponto-cerebellar fibers. The pathophysiology is thought to have a functional or reversible basis but can also reflect in secondary morphologic change. CCD is a well-recognized phenomenon, since the development of new imaging techniques, although scarcely described in neurodegenerative dementias.

RESULTS

To our knowledge this is the first report describing CCD in AD subjects with documentation of both 18F-FDG PET and 11C-PiB PET imaging. CCD in our subjects was explained on a functional basis due to neurodegenerative pathology in the left hemisphere. There was no structural lesion and the symmetric amyloid accumulation did not correspond with the unilateral metabolic impairment.

CONCLUSION

This suggests that CCD might be caused by non-amyloid neurodegeneration. The pathophysiological mechanism, clinical relevance and therapeutic implications of CCD and the role of the cerebellum in AD need further investigation.

A shrunken world - micropsia after a right occipito-parietal ischemic stroke

Micropsia is a rare condition in which patients perceive the outside world smaller in size than it actually is. We examined a patient who, after a right occipito-parietal stroke, subjectively reported perceiving everything at seventy percent of the actual size. Using experimental tasks, we confirmed the extent of his micropsia at 70%. Visual half-field tests showed an impaired perception of shape, location and motion in the left visual field. As his micropsia concerns the complete visual field, we suggest that it is caused by a higher-order compensation process in order to reconcile the conflicting information from the two hemifields.

Walking trajectory in neglect patients

A lateral deviation of the walking trajectory is often observed in stroke patients with unilateral spatial neglect. However, existing research appears to be contradictory regarding the direction of this deviation. The aim of the present study was to gain more insight into the walking trajectory of neglect patients. Twelve right hemisphere stroke patients (six neglect, six no neglect), eight left hemisphere stroke patients (none neglect) and 10 healthy control subjects were instructed to walk towards a target while a two-dimensional ultrasonic positioning system recorded their walking trajectory. Patients' recovery of walking ability was assessed and they were tested for the presence of neglect. Neglect patients showed a larger lateral deviation in their walking trajectory compared to stroke patients without neglect or controls. Neglect patients with good walking ability showed a deviation to the contralesional side. Neglect patients with limited walking ability showed a deviation to the ipsilesional side. Within the neglect group we found no relation between the severity of neglect and lateral deviation. Differences in walking ability may account for the contradictory results between studies regarding the lateral deviation in neglect patients' walking trajectory. We suggest that when a neglect patient's walking ability is limited, walking towards a target becomes a dual task: heading control and walking. A limited walking ability will cause a higher task priority of walking compared to heading control. This shift in task priority may be causing the change in walking trajectory deviation.

Effect of ageing on the ability to adapt to a visual distortion during walking

Degradation of major sensory systems such as proprioception, the vestibular system and vision may be a factor that contributes to the decline in walking stability in older people. In the present study this was examined by introducing a visual distortion by means of prism glasses shifting subject's view 10 degrees to the right while subjects walked towards a target (exposure condition). Shifting the view while walking towards a target will cause subjects to alter their heading in such a way that their walking trajectory describes a curvilinear path. It was expected that older people, when compared to young people, would have greater difficulty adjusting their heading and would show a greater decrease in heading stability, quantified by means of the standard deviation of the lateral position (SDLP). This was indeed the case. When performance in a pre- and post-exposure condition, in which subjects walked without prism glasses, were compared to each other, older people (O group) showed a greater decrease in heading stability than young people (Y group) and middle aged people (M group). Furthermore, it appeared that during the exposure condition adaptation effects were present in the Y and M group, which were absent in the O group. It is discussed that this adaptation is a form of realignment of the proprioceptive and visual system. The absence of realignment in the O group is argued to be caused by degradation of the proprioceptive system, which results in a lowering of the proprioceptive bias of vision.

Functional recovery of gait and joint kinematics after right hemispheric stroke

OBJECTIVE

To gain insight into the relation between changes in gait patterns over time and functional recovery of walking ability in stroke patients.

DESIGN

Cohort study.

SETTING

Inpatient rehabilitation center of a university hospital in the Netherlands.

PARTICIPANTS

Thirteen stroke patients admitted, or awaiting admission, for inpatient rehabilitation 3 weeks poststroke, and 16 healthy control subjects.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

At 3, 6, 12, 24, and 48 weeks poststroke, functional recovery of walking ability was assessed with the Rivermead Mobility Index (RMI) and the Functional Ambulation Categories (FAC). When possible, kinematics of the knee, hip, and pelvis were assessed through gait analysis in an 8 x 4 m gait laboratory. Minimal scores of 8 on the RMI and 4 on the FAC were necessary before patients were classified as functionally recovered.

RESULTS

Patients whose joint kinematics during ambulation had recovered to within the range of the control group showed functional recovery of walking ability. However, some patients whose kinematics had developed toward an abnormal pattern also showed functional recovery.

CONCLUSIONS

Recovery of joint kinematics toward a normal pattern is not required for functional recovery of walking ability. Early recognition of compensatory walking patterns that facilitate functional recovery may have implications for rehabilitation programs.

Ultrasonic motion analysis system--measurement of temporal and spatial gait parameters

The duration of stance and swing phase and step and stride length are important parameters in human gait. In this technical note a low-cost ultrasonic motion analysis system is described that is capable of measuring these temporal and spatial parameters while subjects walk on the floor. By using the propagation delay of sound when transmitted in air, this system is able to record the position of the subjects' feet. A small ultrasonic receiver is attached to both shoes of the subject while a transmitter is placed stationary on the floor. Four healthy subjects were used to test the device. Subtracting positions of the foot with zero velocity yielded step and stride length. The duration of stance and swing phase was calculated from heel-strike and toe-off. Comparison with data obtained from foot contact switches showed that applying two relative thresholds to the speed graph of the foot could reliably generate heel-strike and toe-off. Although the device is tested on healthy subjects in this study, it promises to be extremely valuable in examining pathological gait. When gait is asymmetrical, walking speed is not constant or when patients do not completely lift their feet, most existing devices will fail to correctly assess the proper gait parameters. Our device does not have this shortcoming and it will accurately demonstrate asymmetries and variations in the patient's gait. As an example, the recording of a left hemiplegic patient is presented in the discussion.