Functional topography of the primary motor cortex during motor execution and motor imagery as revealed by functional MRI

Makary, Meena M.,Eun, Seulgi,Soliman, Ramy S.,Mohamed, Abdalla Z.,Lee, Jeungchan,Park, Kyungmo Wolters Kluwer Health | Lippincott Williams Wilkin 2017 NEUROREPORT - Vol.28 No.12

<P>Controversy exists regarding the involvement of the primary motor cortex (M1) during motor imagery (MI) and also regarding the differential somatotopic representation of motor execution (ME) and mental simulation of movement, that is, MI within M1. Although some research reported clear M1 involvement during MI without overt motor output, others did not. However, possible somatotopic representation between execution and imagery has not been clearly investigated to date. The aim of the present study was to aid in the resolution of this controversy by investigating the possible involvement of M1 during MI, and the differential, within M1, somatotopic representation between execution and imagery by quantitatively assessing different location markers such as activation peak and center of mass as well as intensity differences between the two tasks in case of with and without the overlap between the two representations. Forty-one healthy volunteers participated in two functional MRI runs of mouth-stretching ME and MI tasks. Our findings suggest the clear involvement of M1 (BA 4) during MI with lower signal intensity compared with ME, and further showed distinct centers for each representation along the y-axis (anteroposterior plane), with MI showing more involvement of the anterior sector of M1 (BA 4a), whereas ME recruited more of the posterior sector (BA 4p). These results parallel the pioneering findings of a functional distinction between BA 4a and BA 4p, where BA 4a is more involved in the cognitive aspects of MI, whereas BA 4p is more related to executive function, promoting the idea of distinctive somatotopic mapping between execution and imagery within M1 sectors.</P>

Greater corticostriatal activation associated with facial motor imagery compared with motor execution: a functional MRI study

Makary, Meena M.,Eun, Seulgi,Park, Kyungmo Wolters Kluwer Health | Lippincott Williams Wilkin 2017 NEUROREPORT - Vol.28 No.10

<P>Motor imagery (MI) relies on conscious mental simulation of a motor act without overt motor output and can promote motor skill acquisition and facilitate rehabilitation for patients with stroke or neurological conditions. Although a plethora of neuroimaging studies have investigated the neural network of MI regarding different body parts, exploration of the neural correlates to facial MI remains warranted. Here, we used functional MRI with a large cohort of 41 participants who underwent motor execution (ME) and MI runs of mouth-stretching tasks. Then, we carried out conjunction and contrast analyses to investigate the commonalities and differences between the two conditions. Conjunction analysis, representing the shared neural network between ME and MI, showed activation in the primary motor cortex, primary and secondary somatosensory cortices, premotor cortex, parietal lobe, anterior insula, supplementary motor area (SMA) and pre-SMA, thalamus, putamen, and caudate. Contrast analysis showed greater activation of primary motor cortex, primary and secondary somatosensory cortices, SMA, anterior insula, and the thalamus in response to ME than MI and greater activation of the premotor cortex, pre-SMA, putamen, and caudate in response to MI than ME. Interestingly, we found exclusive activation in the anterior cingulate cortex and left ventrolateral prefrontal cortex in response to MI, reflecting the motor inhibition network responsible for blocking the transmission of motor commands to peripheral effectors during mental rehearsal. Taken together, these findings show that, despite the neural overlap between ME and MI, there are different degrees of activation within this overlap, and that MI normally involves motor command inhibition possibly mediated by the anterior cingulate cortex and ventrolateral prefrontal cortex. Copyright (C) 2017 Wolters Kluwer Health, Inc. All rights reserved.</P>

Brain correlates to facial motor imagery and its somatotopy in the primary motor cortex

Soliman, Ramy S.,Lee, Sanghoon,Eun, Seulgi,Mohamed, Abdalla Z.,Lee, Jeungchan,Lee, Eunyoung,Makary, Meena M.,Kathy Lee, Seung Min,Lee, Hwa-Jin,Choi, Woo Suk,Park, Kyungmo Wolters Kluwer Health | Lippincott Williams Wilkin 2017 NEUROREPORT - Vol.28 No.5

<P>Motor imagery (MI) has attracted increased interest for motor rehabilitation as many studies have shown that MI shares the same neural networks as motor execution (ME). Nevertheless, MI in terms of facial movement has not been studied extensively; thus, in the present study, we investigated shared neural networks between facial motor imagery (FMI) and facial motor execution (FME). In addition, FMI somatotopy within-face was investigated between the forehead and the mouth. Functional MRI was used to examine 34 healthy individuals with ME and MI paradigms for the forehead and the mouth. The general linear model and a paired t-test were performed to define the facial area in the primary motor cortex (M1) and this area has been used to investigate somatotopy between the forehead and mouth FMI. FMI recruited similar brain motor areas as FME, but showed less neural activity in all activated regions. The facial areas in M1 were distinguishable from other body movements such as finger movement. Further investigation of this area showed that forehead and mouth imagery tended to lack a somatotopic representation for position on M1, and yet had distinct characteristics in terms of neural activity level. FMI showed different characteristics from general MI as the former exclusively activated facial processing areas. In addition, FME and FMI showed different characteristics in terms of BOLD signal level, while sharing the same neural areas. The results imply a potential usefulness of MI training for rehabilitation of facial motor disease considering that forehead and mouth somatotopy showed no clear position difference, and yet showed a significant BOLD signal intensity variation. NeuroReport 28: 285-291 Copyright (C) 2017 Wolters Kluwer Health, Inc. All rights reserved.</P>

Bacillus amyloliquefaciens k 의 생육과 α - Amylase 생육에 대한 Tunicamycin 의 영향

전촌학조,김기철,산기진수,고월소 한국농화학회 1981 Applied Biological Chemistry (Appl Biol Chem) Vol.24 No.4

The effects of tunicamycin (TM) on the growth and α-amylase productivity of B. amyleliucfaciens K were studied. The minimal growth inhibitory concentration was 0.25㎍/㎖ and its α-amylase was stable up to 50℃. When the saking culture with 1㎍/㎖ of Tunicamycin oaused the change of cell shape from form rod to irregular circular form and the mycelium lysis. the grow th of His-. TM mutant obtained by treatment of TM and ultraviolet ray was similar to that of the parent strain, but the productivity of α-amylase, protease, and RXase was lower than that of the parent.

Bacillus amyloliquefaciens k의 생육(生育)과 ${\alpha}-Amylase$ 생산(生産)에 대한 Tunicamycin의 영향(影響)

김기철,산기진수,고월소,전촌학조,Kim, Ki-Cheul,Yamaski, Makari,Takatsuki, Akira,Tamura, Gakuzo 한국응용생명화학회 1981 Applied Biological Chemistry (Appl Biol Chem) Vol.24 No.4

Bacillus amyloliquefaciens K의 생육(生育)과 ${\alpha}-amylase$ 생산(生産)에 대한 Tunicamycin (TM)의 영향(影響)을 검토(檢討)한 결과(結果) 최소생육저지농도(最少生育沮止濃度)는 $0.25{\mu}\textrm{g}/m\ell$이고 생산(生産)된 ${\alpha}-amylase$의 내열성(耐熱性)은 $50^{\circ}C$이었다. TM 첨가량(添加量)이 $1{\mu}\textrm{g}/m\ell$인 액체배지(液體培地)에서 10시간(時間) 진탕배양(振湯培養)할 경우 균(菌)의 형태(形態)는 간형(桿形)에서 부정형(不定形)의 구형(球形)으로 변형(變形)되었으며 24시간배양(時間培養)으로 용해(溶解)되었다. TM와 자외선의 처리로 분리(分離)한 his-, $TM^{\tau}$ 변이주(變異株)의 생육(生育)은 친주(親株)와 같은 경향(傾向) 이었으나 ${\alpha}-amylase$, protease, 및 RNase의 생산량(生産量)은 떨어지는 경향(傾向)이다. The effects of tunicamycin (TM) on the growth and ${\alpha}-amylase$ productivity of B. amyloliquefaciens K were studied. The minimal growth inhibitory concentration was $0.25{\mu}\textrm{g}/m\ell$ and its ${\alpha}-amylase$ was stable up to $50^{\circ}C$. When the saking culture with $1{\mu}\textrm{g}/m\ell$ of Tunicamycin caused the change of cell shape from form rod to irregular circular form and the mycelium lysis. the grow th of His-, $TM^{\tau}$ mutant obtained by treatment of TM and ultraviolet ray was similar to that of the parent strain, but the productivity of ${\alpha}-amylase$, protease, and RNase was lower than that of the parent.