视觉感觉信息微加工过程研究方法

中南民族大学硕士学位论文视觉感觉信息微加工过程研究方法姓名：谢水清申请学位级别：硕士专业：生物医学工程指导教师：杨仲乐20060525中南民族大学硕士学位论文摘要大脑具有的信息加工能力，远远优于计算机。

如果能够模拟仿生大脑的信息加工，将极大地促进计算机信息科学。

要实现对大脑的信息加工的仿生，就必须研究大脑的信息加工规律。

大脑的信息加工主要的一个部分就是视觉感觉信息加工。

但是视觉感觉信息加工过程研究面临着巨大的困难：即使是一个很简单的视觉信息加工试验现象，也往往出现多个相互矛盾的理论假说。

究其原因，我们发现，自1960年Sperling证明视觉感觉记忆以来，对视觉感觉信息加工的研究（整合，掩蔽，似动，及立体视觉等等），涉及的实际上都是“宏时间”过程，即刺激物持续时间和加工时间在几十毫秒以上的那些加工过程。

而20世纪以来指导自然科学研究，并由此取得丰富成果的“简化归纳”思想，在视觉感觉信息加工研究体现甚少。

为此，本文将“简化归纳”思想移植视觉感觉信息加工过程研究中，并设想“宏时间”过程是由“微时间”过程决定的，把“微时间”过程研究清楚，找到规律，就能了解“宏时间”过程。

在此基础上，本文进一步发展了一种研究视觉感觉信息“微时间”加工过程的方法。

在这种微加工过程研究方法中，需要视觉刺激的呈现时间以及刺激间隔时间十分短暂，以研究在很短时间内，视觉感觉的信息处理机制。

然而，在减少视觉刺激的呈现时间和间隔时间的时候，刺激显示以及对其计时的精度会大大降低，甚至严重的干扰了视觉感觉信息处理的研究。

因此，确保刺激显示以及对其计时的精度，成为人们必须解决的首要技术问题。

现今研究表明，计算机操作系统，监视器，以及鼠标键盘等输入设备都影响着实验精度。

研究人员在这些方面进行了大量的研究，通过各种方法来提高实验精度，并提出了一些的测量方法来验证这些成果。

Hamm JP的研究小组致力于解决DOS系统下刺激显示计时的精度问题，通过设计专门的显示驱动来提高显示计时的精度。

而Forster KI和Forster JC则利用DirectX技术在Windows系统下提高视觉刺激呈现以及鼠标键盘的精度。

为了减少监视器的带来误差，研究人员建议提高显示器的刷新速度。

随着计算机软件和硬件的技术发展，试验误差正在减少，但是监视器所带来的问题依然存在，无论哪一种显示器都存在同样的问题，即显示内容通过串行方式在显示设备上输出，这将带来的很大的误差。

产生这个问题的原因是，通过串视觉感觉信息微加工过程研究方法行方式将图像呈现在监视器屏幕上，在计算机执行显示函数时，数据指针一般并不正好处于对应的刺激物显示的区域，它们有可能还远未到达该区域，也有可能已经从该区域离开。

因此监视器不一定同步显示刺激物。

这个误差在刷新率为100Hz的监视器上，最大可达10ms。

为了解决监视器所带来的问题，在本文利用软件减少误差的方案中，通过DirectX来实时获取对应于监视器扫描线位置的数据指针，实现了单屏显示，准确确定刺激在屏幕上出现的时刻，实现了以刺激在屏幕上出现的时刻为计时起点，将视觉刺激显示的计时精度提高到几十微秒。

综上所述，本文首次将“简化归纳”和“整体统一”思想应用到视觉感觉信息加工研究中，并提出了一系列全新的方法，解决了“简化归纳”和“整体统一”在具体应用中的相关难题。

主要包括以下内容：1. 根据“简化归纳”思想提出刺激显示的微持续和微间隔技术。

利用微持续技术，实现由计算机控制使图像显示的持续时间少到1ms左右的技术。

利用微间隔技术，实现由计算机控制使先后呈现的图像间的间隔少到4ms左右的技术。

2. 根据“整体统一”思想提出逐次综合比较法。

逐次综合比较法，指的是由计算机控制，将微过程逐渐变大，并将变大的微过程与变大前的微过程进行比较。

它是“整体统一”法在视觉感觉信息加工研究中的具体应用。

3. 实现视觉刺激的单屏显示。

单屏显示是指，通过DirectX来实时获取监视器扫描线的位置，实现视觉刺激只在监视器1个刷新周期内显示。

它是微持续和微间隔技术实现的关键技术。

4 实现视觉刺激呈现与计时起点的高度同步。

通过DirectX能够直接访问硬件的性能，实时获取监视器扫描线的位置，从而确定视觉刺激真正呈现在监视器上的时刻，并以此为计时起点，或以此产生触发信号，使得视觉刺激呈现与计时起点精确同步，或视觉刺激呈现与外部其他设备（如数据采集设备）精确同步，同步的误差仅为几十微秒。

5. 提出多种实验精度检测方法。

为了准确直接测量视觉刺激呈现的误差，以及鼠标键盘等输入设备的延时，我们提出一系列准确可行的测量方法。

6. 获得视觉感觉信息微加工过程初步特性。

发现了掩蔽效应和整合效应不能解释的实验现象。

由这些现象，得到了视觉感觉信息微加工过程初步特性。

关键词：视觉感觉信息；简化归纳；微加工过程；视觉刺激；刺激显示中南民族大学硕士学位论文AbstractThe information processing capability of human brain is far excelled than computer. If the information processing style of brain can be imitated by the computer, the computer and information science will be remarkably promoted. However the necessary condition of imitating the information processing style of brain is to research and get the rule of brain information processing. The main part of brain information processing is visual sensory information processing. But the researchers of visual sensory information processing are faced with tremendous trouble: even a simple trial phenomenon of visual sensory information processing, has many theories and explanations which are inconsistent.To find the real reason, we get that the process which is referred by study of visual sensory information processing (including integration, visual mask, appear moving, apparent motion and so on) since that Sperling proved the visual sensory memory in 1960 are macro-time process. This visual stimulus duration is greater than several ten milliseconds in this macro-time process. However the idea of reduction and induction which directed the nature scientific research and got abundance achievements in the whole 20 century is few used in research of visual sensory information processing.For the point, the idea of reduction and induction is transplanted to research of visual sensory information processing in this text, we assume that macro-time process is made up with micro-time process, if we kwon the property of micro-time process, and find the rule of information processing in micro-time process, we will get the property of macro-time process. A method which is used to research visual sensory information processing is developed in this text based on this idea.In this method of researching micro-process, the duration and ISI of stimuli should be very short, such as several milliseconds; in this case, we can study the mechanism of visual sensory information processing in very shot time. However, when we decrease the duration and ISI of stimuli, the accuracy of stimulus present and its timing will be reduced, which will affect the visual sensory information processing research. So it is important to insure the accuracy of stimulus present and its timing, and this is the first thing we should do.视觉感觉信息微加工过程研究方法Researches show that computer OS, computer monitor, mouse and keyboard affect the accuracy in the experiments. Many studies have been done to improve accuracy in visual sensory information processing research, and report some measurement method to check these studies. Hamm JP and his group put solutions of the timing accuracy for visual stimulus in DOS, and improve timing accuracy with designing special display driver. Forster KI and Forster JC improve accuracy of stimulus display, mouse and keyboard in Windows using DirectX. In order to decrease the error taking by computer monitor, researchers suggest increasing the monitor’s refresh rate.As computer software and hardware developing, the error in the experiments is decreasing, but monitor problem still exists, whatever kinds of monitor have the same problem which is the image is serially delivered to the monitor by video card, and this problem will bring great error. Because when function is executed, the stimuli may not appear immediately if the scan line is not at the position on the monitor where the stimuli will be drawn. This delay is caused by the inherent display mode: the top-to-bottom line by line scanning. The scan line may be out of the area where the stimulus will be drawn. It may have not arrived at, or already left, the area. Each factor can introduce a delay and the effects are additive in error. The amount of delay is uncertain and can be as short as a few µs or as long as tens of ms.This approach uses DirectX to monitor the scan line of CRTs, and sets the stimulus onset at the time when scan line arrives at the position where the stimulus is to be drawn. This approach removes the uncertainty in time delay between the activation of display routine and the actual time when the display occurs, improves the accuracy of response time and latency period measurements to within several tens µs.All in all, we first take the idea of reduction and induction and the idea of integration and unification as tools to research visual sensory information processing in micro-process, and develop a series of method to solve the problems in implementing the two ideas.1. Using idea of reduction and induction, we present a stimuli display method with micro-duration and micro-ISI technology by which the stimuli duration is less than 1ms and the stimuli ISI is less than 4ms.2. Using idea of integration and unification, we present a research method which中南民族大学硕士学位论文connects the micro-time process and macro-time process. In the method, the micro-time process gradually increases, and compares with the one before increasing.3. We make the visual stimulus display in a single monitor refresh cycle. It is the critical part of micro-duration and micro-ISI technology.4. This approach sets the stimulus onset time consistent with how the response time is supposed to be measured. We achieved the goal by acquiring the real-time position data of the monitor scan line using DirectX. With a specially developed driver, this solution can generate a trigger signal synchronized with the stimulus onset precisely in all popular Windows systems5. Develop several measurement methods to check the visual stimulus display, mouse and keyboard accuracy.6. Get the preparatory results of visual sensory information processing in micro-process, and find some property of this kind of processing.Key Words: visual sensory information; reduction induction; micro processing; visual stimulus; stimulus display中南民族大学学位论文原创性声明本人郑重声明：所呈交的论文是本人在导师的指导下独立进行研究所取得的研究成果。