Impaired Prefrontal Hemodynamic Maturation in Autism and Unaffected Siblings

BACKGROUND: Dysfunctions of the prefrontal cortex have been previously reported in individuals with autism spectrum disorders (ASD). Previous studies reported that first-degree relatives of individuals with ASD show atypical brain activity during tasks associated with social function. However, developmental changes in prefrontal dysfunction in ASD and genetic influences on the phenomena remain unclear. In the present study, we investigated the change in hemoglobin concentration in the prefrontal cortex as measured with near-infrared spectroscopy, in children and adults with ASD during the letter fluency test. Moreover, to clarify the genetic influences on developmental changes in the prefrontal dysfunction in ASD, unaffected siblings of the ASD participants were also assessed. METHODOLOGY/PRINCIPAL FINDINGS: Study participants included 27 individuals with high-functioning ASD, age- and IQ-matched 24 healthy non-affected siblings, and 27 unrelated healthy controls aged 5 to 39 years. The relative concentration of hemoglobin ([Hb]) in the prefrontal cortex was measured during the letter fluency task. For children, neither the [oxy-Hb] change during the task nor task performances differed significantly among three groups. For adults, the [oxy-Hb] increases during the task were significantly smaller in the bilateral prefrontal cortex in ASD than those in control subjects, although task performances were similar. In the adult siblings the [oxy-Hb] change was intermediate between those in controls and ASDs. CONCLUSION/SIGNIFICANCE: Although indirectly due to a cross-sectional design, the results of this study indicate altered age-related change of prefrontal activity during executive processing in ASD. This is a first near-infrared spectroscopy study that implies alteration in the age-related changes of prefrontal activity in ASD and genetic influences on the phenomena

Physical properties of "kaigoshoku (foods for persons requiring nursing care)": Properties relating to the accidental aspiration of food

食品物性の立場から、食物の誤嚥要因について検索することを目的に、介護食(5%澱粉汁、マッシュポテトほか)の圧縮試験を行った。5%澱粉汁は弾力を示す変曲点を経た後流動を示したのに対し、その他の試料(0, 1, 3%澱粉汁、牛乳、飲むヨーグルト)は測定開始と同時に流動する結果を得た。また5%澱粉汁の圧縮(歪率70%まで)に要したエネルギーはその他の試料の2倍の値であった。これらの結果から、とろみの付いた汁物は摂取直後舌をはじめとする口腔器官によって固体状食物として捉えられた後、やや抵抗を示しながら口腔内に広がっていくと推察される。汁物に澱粉などでとろみを付けることによって発現した汁物の物性によって汁物の誤嚥を防ぎうると考察した。マッシュポテトの変形開始時の圧縮応力は裏ごしいもの1/3値であった。またマッシュポテトはなだらかな上昇曲線を示したが、裏ごし芋は凸凹状の波型曲線を示した。これらの結果から、マッシュポテトは裏ごし芋に比べ軟らかいため摂食・咀嚼し易いと言うことが出来る。また抵抗の少ない咀嚼によって、滑らかで、のみ込み易い食塊状態をとれるのではないかと考察した。これに対し裏ごし芋はボソボソした状態になっていると判断した。裏ごし芋の物性が食塊形成のための咀嚼に問題を引き起こしていると推測され、これが裏ごし芋が誤って気道に紛れ込む(誤嚥)要因と考察した。We conducted compression tests on kaigoshoku (5%starch soup, mashed potatoes, etc.) from the perspective of physical properties of food, with the objective of searching for factors that contribute to accidental aspiration.While 5% starch soup indicated a now that started after passing an inflection point that signified elasticity, the other samples (0, 1, and 3% starch soup, milk, drinkable yogurt) indicated flows that started at the same time as the start of measurement. Additionally, the energy level required for the compression (up to 70% distortion) of 5% starch soup was approximately twice as high as those required for the other samples. These results suggested that viscous soups are first captured as a solid state food by the tongue and oral organs immediately after ingestion, then spread throughout the oral cavity while offering some degree of resistance. We considered that it possible to prevent the accidental aspiration of soups and drinks by the viscosity generated by the addition of such substances as starch.The compression stress of mashed potatoes at the deformation start point was approximately one third of that of strained potatoes. In addition, while mashed potatoes demonstrated a gradual rising curve, strained potatoes showed an uneven, wavy curve. These results indicate that mashed potatoes, being softer than strained potatoes, are easier to ingest and masticate. Also, as they offer less resistance to mastication, we believed that they were better able to take on a bolus form that was smooth in texture and easy to swallow. By comparison, strained potatoes were judged to be in a mealy state. The physical properties of strained potatoes were suspected of causing mastication problems in terms of bolus formation, and we considered that this was a factor that caused strained potatoes to accidentally and their way into the trachea (accidental aspiration)

Physical properties of daily foods and mastication

先に平川らは米飯主食がパンやうどんを主食とする食事に比べ咀曙を促すことが出来ると報告した。本研究ではこの結果を食品物性の面から検索することを目的として,米飯と咀畷様式が米飯と共通するパン類の等速圧縮破断試験を行った。その結果,米飯は荷重0.60Nに破断点を持つなだらかな山形曲線を与え,曲線の形状から粘りがある米飯であると判定した。しかしパン類では,食パンでは荷重14.1N, ロールパンでは33.6Nでほとんど破断された。以上の結果から,パン類では圧縮破断のみの咀啜に対し,米飯の場合には更に(破断のための咀畷に加え),米飯の粘性特性に起因する食塊形成のための咀畷が必要であると考えられた。従って,米飯主食の食事における咀曙回数の促進要因は米飯の粘性によるものと考察した。Previously, Hirakawa et al. reported that cooked rice as main foods was able to promote more mastication in comparison with bread or udon noodles as main foods.In this study, for the purpose of searching their results from the viewpoints of physical properties of foods, we have made the uniform velocity compressive rupture tests of cooked rice and sorts of bread which have a type of mastication similar to that of rice, As the results, cooked rice gave a gently sloping curve which had the rupture point at the load value of 0.60N.From the shape of curve, it is judged that cooked rice is viscous. In case of bread, however, a leaf of bread was almost ruptured at the load value of 14.lN and a roll of bread at 33.6N.Based on the above results, we have considered that mastication is needed solely for compressive rupture in case of sorts of bread, and that, on the contrary, in case of cooked rice, more mastication is necessary to form a mass of foods caused by stickiness of cooked rice (in addition to mastication for rupture). It is, therefore, concluded that the promotion factor for the number of mastication times in taking a meal with cooked rice as main foods is originated in the viscosity of cooked rice