The past decade has seen several lines of research converge on the idea that phase-amplitude cross-frequency coupling (CFC)   may play an important functional role in local computation and long-range communication in large-scale brain networks.   The discovery that strong CFC exists in multiple brain areas including the neocortex, hippocampus, and basal ganglia suggests that CFC reflects functional activation of these areas.   The finding that the exact frequencies coupled together vary as a function of area and task imply that independent channels of coupling may coexist simultaneously during task performance.   The dynamic regulation of coupling strength indicates that CFC has the necessary temporal resolution required for the effective modulation of distinct functional networks.   Finally, the discovery that hippocampal CFC strength is correlated with learning task performance suggests that phase-amplitude CFC may help regulate the network of synaptic connections vital for memory and learning.   Together, these findings suggest a framework where phase-amplitude CFC parses neuronal computation into discrete chunks of activity that are ideal for attention, learning, and memory, and that these multi-scale building blocks are entrained to both rhythmic, external sensory and motor activity as well as the internal fronto-limbic activity associated with motivation, decision making, and memory.

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Recently, numerous brain imaging studies have been performed to clarify the pathophysiology of depression.   These studies suggest that the neural network, physiological function, and their interaction are related to the development of depressive symptoms.   In this article, we present our neuroimaging studies employing functional magnetic resonance imaging (fMRI)   on the neurophysical basis of depression involving the brain.   At first, because of the influence of stressful life events on depression, sex differences in the cognition of psychosocial stressors, was examined.   The results revealed the importance of prefrontal cortex (PFC)   and amygdala in the cognition of the stressors.   Next, some important changes in the PFC were shown in depression using well-known neuropsychological tasks and originally created tasks related to depressive symptoms.   Moreover, these changes in the brain might be a possible biological marker of the treatment response and functional recovery.   Finally, we focused on the neurophysiological role of serotonin in higher cognitive function in the human brain.   It was found that serotonin differentially regulated reward predictive activities at different time scales in the striatum-PFC network.   From these findings, neurophysical basis of the cognition, the pathophysiology, the treatment of depression were discussed.

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The problems with regard to analysis on the functional imaging were described.   The statistics and analytical processes are considered to be important.   Recent advances on computer technology as well as the improvement of the image analysis algorithm provide us an easy solution from the inadequate data.   Researchers should understand the process of the analytical process and statistics.   Tips for analysis of the image were described.   In addition, recent topic related to default mode network was address.

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Executive function is defined as a brain function dedicated to sustain a proper mental set for the purpose of accomplishing a future goal, and comprises of four steps of 1)   the goal formation, 2)   planning, 3)   goal-directed actions and 4)   effective performance [Lezak MD 1982]. More specifically, one has first to set a future goal with definite intention, secondly to consider and select most appropriate strategies that should be taken, thirdly to initiate and sustain constantly goal-directed actions while adding appropriate amendments to the plans and methods, and finally to organize the most efficient strategies by reviewing the past progresses as well as estimating the extent of future courses still left before reaching the goal.
      Among various cognitive functions, executive function may be regarded as a higher-order function that controls efficiency and purpose-directed operations of other subordinate cognitive functions such as memory, language and visuospatial skills.
      Executive function may be assessed globally by short bedside tests represented by the Frontal Assessment Battery [Dubois B et al. 2000] and more complex and detailed test batteries such as the Behavioural Assessment of the Dysexecutive Syndrome [Wilson BA et al. 1996]. Further, “executive function”, when taken as a general umbrella term, may comprise of several associated brain functions, each of which represents specific aspect of “executive function”. Among these functions are 1)   divided attention and a capacity to manage multiple and simultaneous tasks that may be tested by the “Kana Hiroi” (phonemic letter picking-up)   Test and the Trail Making Test, 2)   capability for mentalset shifting assessed by the Stroop Test, 3)   psychomotor speed tapped by the semantic or phonemic word fluency test, and 4)   abilities in recursive speculations that may be tested by the Wisconsin Card Sorting Test or Tower of Hanoi.
      Dysexecutive syndrome may be elicited by damage to the dorsolateral prefrontal cortex and/or its projection to the striatum, namely the dorsolateral prefrontal circuit, one of five functional neural circuits between the frontal lobes and the striata.   Cognitively associated fronto-striate circuits also include the lateral orbitofrontal circuit that is involved in inhibitory control of behaviors, and anterior cingulate circuit that is involved in maintenance of initiatives and interests in the outside milieu. Damage to the former may induce disinhibition and antisocial behaviors, and damage to the latter may cause inertia and apathy. Dysexecutive syndrome may be accompanied by other frontal symptoms such as behavioral and emotional impairment and these additional impairments may alternatively hamper executive function further.

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[in Japanese]

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These days, Yokukan-san is effective in behavioral and psychological symptoms of dementia.   Kampo-medicine understands senility as the deficiency of Kidney.   It is easy to connect psychological and somatic symptoms with five organs-function of Kampo-medicine by using the psychosomatic chart of five organs.   We expect that Keishi-ka-ryukotuborei-to and Saikokeishikankyo-to are researched harder in senile psychosomatic symptoms.   We should permit treatment using Kampo according to diagnosis of modern medicine for research, but Kampo-medicine give us the great ability of cure for symptoms, when is branched from modern diagnosis.

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[in Japanese]

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The Mini Mental State Examination (MMSE)   is a screening test which has been used widely for dementia.   evaluation.   This study aimed to establish the validity and reliability of the Japanese version of MMSE (MMSE-J)    (Sugishita, 2006)   based on data from 313. subjects (normal control : 107, MCI : 154 and AD : 52).   MMSE-J has two varieties : one (the serial 7s version)   uses the serial 7s task as the Attention and Calculation task. the other (the backward repetition version)   uses the backward repetition of word as the task. Predictive validity of MMSE-J was excellent (the serial 7s version : sensitivity 0.86, specificity 0.89, the backward repetition version : sensitivity 0.88, specificity 0.94).
      The test-retest reliability of MMSE-J was estimated on the 142 subjects who were tested twice (the first test and the second test 6months after the first test)   to be 0.81 for the serial 7s version and 0.77 for the backward repetition version.   The predictive validity of MMSE-J was excellent (the serial 7s version : sensitivity 0.83, specificity 0.92, the backward repetition version : sensitivity 0.83, specificity 1.00).   In conclusion, MMSE-J is a sensitive screening test in detecting dementia.

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Objective: The objective of this study was to prove the validity and reliability of 9 of the 29 tasks on the new computerized assessment software, the Higher Brain Functional Balancer (HBFB).
Methods: A total of 70 apparently healthy elderly subjects (aged 63 to 86 y;27 males, 43 females)   participated in this prospective study.   The association between the MMSE and HBFB was tested by Pearson’s correlation coefficient analysis;internal consistency of 9 tasks of the HBFB was checked by Cronbach’s coefficient alpha (Cronbach’s α), and test-retest reliability of each task was established using intra-class correlations (ICC).   For test-retest reliability, subjects were administered 9 tasks of the HBFB twice at a 1-month interval.   The test-retest HBFB quotient, data on age, length of education, and results of the Mini-Mental State Examination (MMSE)   were recorded.
Results: Pearson’s correlation coefficient analysis showed that the state of cognitive function according to the total scores of the MMSE correlated significantly with the total quotients of the HBFB (r=0.356, p=0.002).   The 9 tasks of the HBFB had appropriate internal consistency (Cronbach’s α=0.735).   Test-retest reliability analysis indicated that the “modified Trail Making Test”, “Flashing-Light Memory”, “Story” and “Route-99” tasks on the HBFB had fair-to-good reliability (ICC=0.364-0.742) ;however, reliability was poor with regard to scores of the other 5 tasks.
Conclusions:This study provides evidence for the validity of total quotients of all tasks for screening of total cognitive function and for the reliability of 4 of the 9 tasks from the HBFB with regard to cognitive function in elderly people.

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