Mental arithmetic modulates temporal variabilities of finger-tapping tasks in a tempo-dependent manner.

Background: Several psychiatric diseases impair temporal processing. Temporal processing is thought to be based on two domains: supra-second intervals and sub-second intervals. Studies show that temporal processing in sub-second intervals is mainly an automated process. However, the brain functions involved in temporal processing at each time scale remain unclear. We hypothesized that temporal processing in supra-second intervals requires several brain areas, such as the ventrolateral prefrontal cortex, intraparietal sulcus (IPS), and inferior parietal lobe, corresponding to various cognitions in a time scale-dependent manner. We focused on a dual-task paradigm (DTP) involving simultaneous performance of cognitive and motor tasks, which is an effective method for screening psychomotor functions; we then designed a DTP comprising finger tapping at various tempi as the temporal processing task and two cognitive tasks (mental arithmetic and reading) that might affect temporal processing. We hoped to determine whether task-dependent interferences on temporal processing in supra-second intervals differed depending on the cognitive tasks involved. Methods: The study included 30 participants with no history of neuromuscular disorders. Participants were asked to perform a DTP involving right index finger tapping at varying tempi (0.33, 0.5, 1, 2, 3, and 4 s inter-tapping intervals). Cognitive tasks comprised mental arithmetic (MA) involving three-digit addition, mental reading (MR) of three- to four-digit numbers, and a control (CTL) task without any cognitive loading. For comparison between tasks, we calculated the SDs of the inter-tapping intervals. Participants' MA abilities in the three-digit addition task were evaluated. Results: The MA and MR tasks significantly increased the SDs of the inter-tapping intervals compared to those of the CTL task in 2-3 s and 3-4 s for the MA and MR tasks, respectively. Furthermore, SD peaks in the finger-tapping tasks involving MA were normalized by those in the CTL task, which were moderately correlated with the participants' MA ability (r = 0.462, P = 0.010). Discussion: Our results established that DTP involving the temporal coordination of finger-tapping and cognitive tasks increased temporal variability in a task- and tempo-dependent manner. Based on the behavioral aspects, we believe that these modulations of temporal variability might result from the interaction between finger function, arithmetic processing, and temporal processing, especially during the "pre-semantic period". Our findings may help in understanding the temporal processing deficits in various disorders such as dementia, Parkinson's disease, and autism.

Educational Program Using Robots for Preventing Cognitive Decline of Elderly Persons.

An expected surge of dementia patients in Japan indicates a pressing need to establish countermeasures. As described herein, by developing an educational program for elderly people using robots, we performed a demonstration experiment. Results revealed that involvement of elderly people with robots enhances their enjoyment, indicating a future direction of cognitive decline prevention education for elderly people.

Telecommunication system for children undergoing stem cell transplantation.

BACKGROUND: Isolation in a germ-free unit is a stressful experience for pediatric patients undergoing hematopoietic stem cell transplantation (HSCT). To reduce the psychological distress of such children, a Web-based telecommunications system was developed. METHODS: The authors developed a telecommunication system that linked a laminar air flow (LAF) room that had a high efficiency particulate air filter with the hospital school/patients' homes via the Internet. Fifteen children isolated in the LAF room for allogeneic HSCT were enrolled in this study. The present study evaluated whether the system was feasible for the patients during the acute phase of HSCT. RESULTS: In 10 patients, the proportion of days when they telecommunicated with teachers and/or other patients in the hospital school was 64.6 ± 32.3%. The telecommunication with the hospital school facilitated the continuation of school study under teachers' guidance, reducing the problem of lost schooling. In 13 patients, the proportion of days when they telecommunicated with their homes was 68.0 ± 34.8%. Ten of them frequently telecommunicated with their family members (especially siblings), and three patients called out to their pets at home. The incidence of telecommunication on the days when the patients had HSCT-related symptoms including vomiting did not differ from that of telecommunication on the days when no symptoms were evident. CONCLUSIONS: A telecommunication system linked to a hospital school and/or the patients' homes is feasible for children undergoing HSCT, and may improve their health-related quality of life. A larger, prospective study is required to evaluate whether the telecommunication system can reduce HSCT-associated psychological and psychiatric symptoms.

Reduced intestinal fat absorptive capacity but enhanced susceptibility to diet-induced fatty liver in mice heterozygous for ApoB38.9 truncation.

Fatty liver is prevalent in apolipoprotein B (apoB)-defective familial hypobetalipoproteinemia (FHBL). Similar to humans, mouse models of FHBL produced by gene targeting (apob(+/38.9)) manifest low plasma cholesterol and increased hepatic triglycerides (TG) even on a chow diet due to impaired hepatic VLDL-TG secretive capacity. Because apoB truncations shorter than apoB48 are expressed in the intestine, we examined whether FHBL mice may have limited capacity for intestinal dietary TG absorption. In addition, we investigated whether FHBL mice are more susceptible to diet-induced hepatic TG accumulation. Fat absorption capacity was impaired in apoB38.9 mice in a gene dose-dependent manner. Relative fractional fat absorption coefficients for apob(+/+), apob(+/38.9), and apob(38.9/38.9) were 1.00, 0.96, and 0.71, respectively. To raise hepatic TG, we fed high-fat (HF) and low-fat (LF) pellets. Hepatic TG level was observed in rank order: HF > LF > chow. On both LF and HF, liver TG level was higher in the apob(+/38.9) than in apob(+/+). Hepatic TG secretion remained impaired in the apob(+/38.9) on the HF diet. Thus the FHBL mice are more susceptible to diet-induced fatty liver despite relatively reduced intestinal TG absorption capacity on a HF diet.

Apolipoprotein B is synthesized in selected human non-hepatic cell lines but not processed into mature lipoprotein.

We studied apolipoprotein B100 (apoB) metabolism in a series of non-hepatic cell lines (HT29 colon adenocarcinoma, HeLa cervical epithelioid carcinoma, and 1321N1J astrocytoma human cell lines) and in the human hepatoma cell line HepG2. ApoB mRNA was detected by reverse transcription polymerase chain reaction in each non-hepatic cell line. ApoB was detected in HepG2 cells by immunoprecipitation, Western blotting, and immunocytochemistry using a polyclonal anti-human low-density lipoprotein (LDL) antibody, an anti-human apoB peptide antibody, and several monoclonal anti-apoB antibodies. ApoB was identified in the three non-hepatic cell lines by each method using the anti-apoB peptide and monoclonal antibodies, but not with the anti-LDL antibody. Immunocytochemistry indicated that epitopes of apoB were evident throughout the endoplasmic reticulum, and gel mobility of newly labeled apoB and immunoblot with anti-ubiquitin showed that apoB was highly ubiquinated in non-hepatic cells. The observations that apoB is synthesized in non-hepatic cell lines but never recognized by the anti-LDL antibody suggests that apoB is not processed into a nascent lipoprotein in these cells. Immunocytochemical localization of apoB epitopes at many locations throughout non-hepatic cells raises the exciting possibility that apoB can be used for other purposes in these cells.