Verbal or Visual Memory Score and Regional Cerebral Blood Flow in Alzheimer Disease

The Effectiveness of a Multimodal Brain Empowerment Program in Mild Cognitive Impairment: A Single-Blind, Quasi-Randomized Experimental Study

The present study aimed to determine a multimodal brain empowerment (MBE) program to mitigate the modifiable risk factors in mild cognitive impairment (MCI), and its therapeutic effects are unknown. MBE encompassing (1) tDCS, light therapy, computerized cognitive therapy (TLC) and (2) robot-assisted gait training, music therapy, and core exercise (REM) interventions were randomly assigned to 20 healthy young adults and 20 older adults with MCI. The electroencephalography (EEG) power spectrum and topographic event-related synchronization (ERS) analysis were used to assess intervention-related changes in neural activity during the MBE program. Outcome: The EEG results demonstrated that both multimodal TLC and REM decreased delta waves and increased theta, alpha, and beta waves (p < 0.001). ERS showed increased neural activation in the frontal, temporal, and parietal lobes during TLC and REM. Such enhanced neural activity in the region of interest supports potential clinical benefits in empowering cognitive function in both young adults and older adults with MCI.

Cortical thickness of the left parahippocampal cortex links central hearing and cognitive performance in aging

Hearing impairment is considered a leading modifiable risk factor of cognitive decline and dementia. While most evidence has been established on clinical assessment of peripheral hearing loss, understanding of how central hearing in real-world conditions is associated with cognitive aging is limited. This study analyzed the data of 473 unrelated healthy adults aged 36-100 years old from the Lifespan Human Connectome Project in Aging. Central hearing was evaluated using the Words-in-Noise decibel threshold. Cognitive functions were evaluated by the performance on cognitive tests, and cortical thickness was estimated from magnetic resonance imaging (MRI) data. Here, we show that a higher hearing threshold was associated with a lower performance on immediate and delayed episodic memory retrieval, switching aspect of executive function, working memory, reading decoding, and vocabulary comprehension. Cortical thickness in the left parahippocampal cortex (lPHC) was negatively associated with the hearing threshold and acted as a significant partial mediator in the association of central hearing with immediate recall, switching, reading decoding, and vocabulary comprehension. These findings suggest that cortical thickness in the lPHC, an early target of dementia, partially links central hearing and performance in multiple cognitive domains in aging.

Self-perception and anticipated efficacy of the anti-dementia multimodal program in 100 older adults with mild cognitive impairment

BACKGROUND

Effective and sustainable interventions are clearly needed for mild cognitive impairment (MCI) patients. Despite the clinical importance of the multimodal intervention approach, only one study using a multimodal approach demonstrated promising improvements in memory, attention, and executive functions, which also correlated with functional magnetic resonance imaging (MRI) blood oxygenation level dependent (BOLD) changes in cerebral activation in 50 MCI patients.

OBJECTIVE

To investigate the self-perception and anticipated efficacy of each element of the BRAIN-FIT multimodal intervention program (robotic-assisted gait training (RAGT), computerized cognitive therapy, music, light, transcranial direct current stimulation (tDCS), and diaphragmatic breathing exercises) and the correlation between memory, concentration, depression, and sleep in older adults with MCI.

METHODS

One hundred participants (mean±standard deviation: 8.63±78.4 years; 47 women) with MCI were recruited from a major university medical center and community dementia relief center. The survey questionnaire comprised four domains with 21 questions, including four pertaining to general demographic characteristics, eight related to exercise and activity, three related to sleep, and nine related to the BRAIN-FIT program. Chi-squared test was used to analyze the Likert scale data. The descriptive frequencies were calculated. Additionally, Spearman's rho statistics measure the rank-order association. The statistical significance was at P <  0.05.

RESULTS

A strong correlation was observed between memory and concentration (r = 0.850, P = 0.000), memory and depression (r = 0.540, P = 0.000), memory and sleep (r = 0.502, P = 0.000), concentration and depression (r = 0.602, P = 0.000), concentration and sleep (r = 0.529, P = 0.000) and sleep and depression (r = 0.497, P = 0.000). The correlation between medical services and sleep (r = 0.249, P = 0.012) was moderate. The chi-square test revealed a significant difference in memory and low-intensity duration of exercise (χ2[3,N = 100] = 11.69, P = 0.01), concentration and high-intensity exercise duration (χ2[3,N = 100] = 10.08, P = 0.02), concentration with low-intensity exercise duration (χ2[3,N = 100] = 21.11, P = 0.00), depression with high-intensity (χ2[3,N = 100] = 10.36, P = 0.02), high-intensity duration of exercise (χ2[3,N = 100] = 10.48, P = 0.02); low-intensity (χ2[3,N = 100] = 7.90, P = 0.48), and low-intensity duration of exercise (χ2[3,N = 100] = 9.69, P = 0.02). Additionally, significant differences were observed between sleep and high-intensity (χ2[3, N = 100] = 10.36, P = 0.02), low-intensity (χ2[3, N = 100] = 18.14, P = 0.00), and low-intensity duration of exercise (χ2[3, N = 100] = 18.30, P = 0.00). Among the participants 5% answered RAGT, and 20% responded that they had experienced computerized cognitive therapy. Music therapy (20 %), diaphragmatic breathing exercises (45 %), and light therapy (10 %) were used. No patient had experienced tDCS. Conversely, 11% of the participants answered RAGT for programs they wanted to experience and 21% responded to computerized cognitive therapy. 25% of music therapy, 22% of diaphragmatic breathing exercises, 5% of light therapy, and 16% of tDCS participants said they wanted to experience it. Finally, 63% of the participants wanted to participate in the BRAIN-FIT program.

CONCLUSION

The present study's results provide clinical evidence-based insights into the utilization of BRAIN-FIT in MCI to maximize cognitive score improvement of memory, concentration, depression, and sleep. Therefore, when designing the BRAIN-FIT, six intervention items were set in proportion to the preference based on the survey, to reduce participants' feeling of repulsion. The program was configured according to exercise intensity.

Neural Correlates of Cognitive Performance in Alzheimer's Disease- and Lewy Bodies-Related Cognitive Impairment

BACKGROUND

Clinicopathological studies have demonstrated that the neuropsychological profiles and outcomes are different between two dementia subtypes, namely Alzheimer's disease (AD) and Lewy bodies-related disease.

OBJECTIVE

We investigated the neural correlates of cognitive dysfunction in patients with AD-related cognitive impairment (ADCI) and those with Lewy bodies-related cognitive impairment (LBCI).

METHODS

We enrolled 216 ADCI patients, 183 LBCI patients, and 30 controls. Cortical thickness and diffusion tensor imaging analyses were performed to correlate gray matter and white matter (WM) abnormalities to cognitive composite scores for memory, visuospatial, and attention/executive domains in the ADCI spectrum (ADCI patients and controls) and the LBCI spectrum (LBCI patients and controls) separately.

RESULTS

Memory dysfunction correlated with cortical thinning and increased mean diffusivity in the AD-prone regions, particularly the medial temporal region, in ADCI. Meanwhile, it only correlated with increased mean diffusivity in the WM adjacent to the anteromedial temporal, insula, and basal frontal cortices in LBCI. Visuospatial dysfunction correlated with cortical thinning in posterior brain regions in ADCI, while it correlated with decreased fractional anisotropy in the corpus callosum and widespread WM regions in LBCI. Attention/executive dysfunction correlated with cortical thinning and WM abnormalities in widespread brain regions in both disease spectra; however, ADCI had more prominent correlation with cortical thickness and LBCI did with fractional anisotropy values.

CONCLUSIONS

Our study demonstrated that ADCI and LBCI have different neural correlates with respect to cognitive dysfunction. Cortical thinning had greater effects on cognitive dysfunction in the ADCI, while WM disruption did in the LBCI.

The Relationship Between Retinal Nerve Fiber Layer Thickness and Clinical Symptoms of Alzheimer's Disease

Background/Aim: Retinal nerve fiber layer (RNFL) thickness (RT), which can reflect the status of the retinal optic nerve cells, may be affected in patients with Alzheimer's disease (AD). There are few studies on the correlation of RT of patients with AD (AD-RT) with clinical symptoms of various cognitive domains, neuropsychiatric symptoms, and activities of daily living (ADL). This study is to investigate the relationships between RT and the abovementioned clinical symptoms of AD.

Methods: A total of 96 patients with AD were included in this study. RT was measured in these patients using optical coherence tomography (OCT). Demographic variables, RT, and clinical symptoms were compared between the normal and the abnormal AD-RT groups. Clinical symptoms, including cognitive symptoms, neuropsychiatric symptoms, and ADL, were evaluated using a series of rating scales.

Results: The relationships between RT and cognitive symptoms scores were analyzed in patients with AD. Reduced RT was found in 54.4% of patients with AD. The average RT, RT of the superior 1/2 quadrant, and RT of the inferior 1/2 quadrant of both eyes were all significantly decreased in the abnormal AD-RT group (p < 0.001). Overall cognitive function and performance in multiple cognitive domains, including memory, language, attention, and executive function, were also significantly impaired in the abnormal AD-RT group (p < 0.05). For lower RT value, the global cognitive function and the performance in multiple cognitive domains were worse. ADL was significantly compromised in patients with AD having lower RT values (p < 0.05).

Conclusions: Lower RT value appear to be correlated with cognitive impairment, and RT may be an indicator of cognitive decline in patients with AD. Further studies are required to confirm our findings.

[¹⁸F]THK5351 PET Imaging in Patients with Mild Cognitive Impairment

Background and Purpose

Mild cognitive impairment (MCI) is a condition with diverse clinical outcomes and subgroups. Here we investigated the topographic distribution of tau in vivo using the positron emission tomography (PET) tracer [¹⁸F]THK5351 in MCI subgroups.

Methods

This study included 96 participants comprising 38 with amnestic MCI (aMCI), 21 with nonamnestic MCI (naMCI), and 37 with normal cognition (NC) who underwent 3.0-T MRI, [¹⁸F]THK5351 PET, and detailed neuropsychological tests. [¹⁸F]flutemetamol PET was also performed in 62 participants. The aMCI patients were further divided into three groups: 1) verbal-aMCI, only verbal memory impairment; 2) visual-aMCI, only visual memory impairment; and 3) both-aMCI, both visual and verbal memory impairment. Voxel-wise statistical analysis and region-of-interest -based analyses were performed to evaluate the retention of [¹⁸F]THK5351 in the MCI subgroups. Subgroup analysis of amyloid-positive and -negative MCI patients was also performed. Correlations between [¹⁸F]THK5351 retention and different neuropsychological tests were evaluated using statistical parametric mapping analyses.

Results

[¹⁸F]THK5351 retention in the lateral temporal, mesial temporal, parietal, frontal, posterior cingulate cortices and precuneus was significantly greater in aMCI patients than in NC subjects, whereas it did not differ significantly between naMCI and NC participants. [¹⁸F] THK5351 retention was greater in the both-aMCI group than in the verbal-aMCI and visualaMCI groups, and greater in amyloid-positive than amyloid-negative MCI patients. The cognitive function scores were significantly correlated with cortical [¹⁸F]THK5351 retention.

Conclusions

[¹⁸F]THK5351 PET might be useful for identifying distinct topographic patterns of [¹⁸F]THK5351 retention in subgroups of MCI patients who are at greater risk of the progression to Alzheimer's dementia.

Dissociation of the subjective and objective bodies: Out-of-body experiences following the development of a posterior cingulate lesion

An out‐of‐body experience (OBE) is a phenomenon whereby an individual views his/her body and the world from a location outside the physical body. Previous studies have suggested that the temporoparietal junction (TPJ), the brain region responsible for integrating multisensory signals, is responsible for OBE development. Here, however, we first present a case of OBE after brain tumour development in the posterior cingulate cortex (PCC). The patient was a 46‐year‐old right‐handed female; she underwent brain surgery. She reported that she had experienced OBEs several times monthly (during daily life) before surgery but never after surgery. She defined her OBEs explicitly; she drew pictures. Her OBEs exhibited phenomenological, overt dissociation of the subjective and objective bodies. We discuss the mechanisms underlying this phenomenon and the relationship between OBEs and the PCC in terms of anatomical and functional brain connectivity. Our case sheds some light on the mechanism involved in creating spatial (dis)unity between the self and the body.