Biomedical subjects

Mo-wei Shen

Publications and source records attributed to Mo-wei Shen.

5 recordsLinked to original sources

PubMed2005

[Observation of the cognition and the velocities of blood in the brain in cerebral arteriosclerosis and infarct patients].

OBJECTIVE: To observe the change of the cognition and the supply of blood in brain in healthy people and patients with arteriosclerosis (AS) and cerebral infarct. METHOD: 1) control group: healthy people, 30 cases. 2) AS group: 22 cases with cerebral arteriosclerosis. Cerebrovascular infarct patients were divided into two groups. 3) 2W group: 21 cases, the patients' course of disease was shorter than two weeks. 4) 6M group: 20 cases, the patients' course of disease was from six months to four years. All cases were checked with cognitive P300 and transcranial doppler ultrasound (TCD) and mini-mental status examination (MMSE). RESULT: The result revealed that the P300 incubation period in 2W group, 6M group and the AS group was remarkable extend than the control group (P<0.01), meanwhile the period of the 6M group was longer than the AS group (P<0.05); the amplitude of the wave of the 2W group and 6M group were shorter than the control group (P<0.05; 0.05). The velocities of bilateral MCA and right ACA were remarkable improved in AS group (P<0.05; 0.01), and the velocities of left MCA both in 2W and 6M group, the right ACA and BA in 6M group were remarkably decreased than the control group (P<0.05; 0.01). The grades of MMSE in all patients were lower than the control group and the grades in 6M group was lower than the AS group. CONCLUSION: There are some changes in the P300 and abnormality of brain blood supply in the cerebral infarct patients and AS patients. The longer the course, the more serious of the cognition with the patients.

Adult↗

PubMed2004

[An event-related potential study the on information processing of binocular disparity in random-dot stereogram].

OBJECTIVE: To study the effects of discontinuous-continuous disparity gradient, uncrossed-crossed disparity and small-large disparity in random-dot stereogram (RDS) on the event-related potentials (ERPs). METHOD: Behavioral data and ERP were recorded when 16 healthy participants (8 males and 8 females) with normal depth perception were performing the task, in which the stereopsis were generated by red-blue glasses. RESULT: 1) The accuracy in discontinuous disparity gradient was higher than that in continuous disparity gradient, and the accuracy in large disparity was higher than that in small one. 2) Discontinuous disparity gradient elicited shorter N160 latency and larger N350 amplitude than continuous disparity gradient did. Compared with uncrossed disparity, crossed disparity elicited shorter N350 latency. In addition, large disparity elicited shorter N160 latency and larger P280 amplitude than small disparity did. CONCLUSION: The effect of disparity gradient on disparity information processing is significant, and the discontinuous disparity gradient has its processing advantage. Latency of N160 and amplitude of P280 is correlated with the information processing of the size of disparity. N350 component is correlated with the information processing of the uncrossed-crossed information of disparity.

Adult↗

PubMed2003

[A study on visual search and selection of pull-down menu].

OBJECTIVE: To explore the characteristics of user's visual search and selection through interaction with pull-down menus. METHOD: The visual search time and selection time of interaction were recorded by eye tracking system, when 14 participants were performing the task of pull-down menu selection, with different menu length, type of menu item and position of target item. RESULT: It was found that selection time was influenced jointly by menu length, type of menu item and target location, while visual search time was only influenced by target location. CONCLUSION: The results of this experiment support the hypothesis that the pull-down menu was characteristic of serial, self-terminated and top-down.

Adult↗

PubMed2003

[Spatial and temporal characteristic of eye movement in human-computer interface design].

OBJECTIVE: To examine the related spatial and temporal characteristics of eye movement in HCI design and to provide ergonomic parameters to optimize the HCI design based on eye tracking. METHOD: Task time, selected error and timeout numbers were recorded automatically, when 12 participants were performing the task of target selection, with different object size, space and dwell time. RESULT: It was significantly found that task time was influenced by object size and dwell time, the selected error was influenced by object space and dwell time significantly. CONCLUSION: The dwell time, object size and object space are all important to optimize the HCI design based on eye tracking. We recommend that the dwell time should be 500 ms, the object size and object space should be not less than 1.5 degrees and 1.0 degrees respectively for the normal interactive systems.

Adult↗

PubMed2002

[Study on sensitivity of event-related EEG sychronization and desychronization visual memory load].

Objective. To examine the effect of visual working memory load on the event-related EEG synchronization and desynchronization. Method. EEG was recorded when 12 normal participants were performing the visual spatial matching task and the abstract geometrical figure matching task in the n-back paradigm in which the memory load varied from 1 to 3. Result. Theta ERS was observed along with alpha ERD. As the memory load increased, the 6-8 Hz ERS decreased and the alpha ERD increased. The theta ERS and alpha ERD elicited by the figure matching task were larger than those in the visual spatial matching task. The fact that most of the differences were observed in the CZ and FZ electrodes was in line with the view that the activation of attention and working memory was often found in prefrontal and parietal regions. Conclusion. The event-related EEG synchronization and desynchronization varies with the visual memory load and therefore are good indicators of memory load.

Adult↗