摘要
本实验采用行为学的宏观观察与大脑额叶单个神经元活动的微观分析相结合的方法,对9只成年猕猴学习、记忆、辨别、注意、决策等几种基础智力因素的神经机制进行了研究。共设计和编制了三套作业对猕猴进行训练。要求动物根据作业中出现的各种灯光信号,对一杠杆进行操作。每套作业都由4个时期组成。不同作业的不同时期所包含的智力因素不同。作业Ⅰ的第3期主要与注意有关,第4期主要与视觉辨别有关。作业Ⅱ的第3期主要与躯体热痛觉辨别有关。作业Ⅲ的第2期主要与视觉辨别有关,第3期主要与短期记忆有关。此外,在三套作业的第4期都包含有决策因素。待动物学会作业后,在进行作业操作的同时,在大脑额叶共记录了216个作业相关神经元。这些神经元的活动分别与辨别、短期记忆、注意和决策有关。对这些神经元的活动特点和规律进行了分析。额叶神经元的辨别机能,主要不是对刺激物的物理属性,而是对其信号意义进行辨别。这是额叶神经元不同于感觉神经元的一个显著特点。额叶神经元的注意机能与短期记忆机能有着密切的关系,与短期记忆有关的神经元也与注意有关。这一实验结果为心理学上关于“注意是促使感觉记忆向短期记忆过渡的主要因素”这一论点首次提供了神经生理学依据。额叶神经元在作业操作中的反应是在学习过程中逐渐形成的。后天的学习训练,对于额叶神经元认知功能的发展,具有良好的促进作用。本研究发现,与基础智力因素有关的神经元多集中在大脑额叶弓状沟上支内侧的狭小范围内,形成一个功能区。用冷冻阻滞的方法取消这个区域的功能后,猕猴进行智力活动的能力明显下降,作业的正确率降低到随机水平。阻滞解除后,正确率可完全恢复。这一新的功能区的发现,为进一步研究智力活动神经基础、研究基础智力相关神经元的中枢递质特性和代谢特点,进而寻求改善和提高人的智力素质和工作能力的有效方法等,打下了基础。另一方面,对于进一步进行大脑智力活动神经回路和神经网络的生物原型研究,也有重要意义。
Experiments were carried out on 9 rhesus monkeys. The monkeys were trained with 3 tasks, in which some basic intelligence factors were involved in different periods, i.e. , visual discrimination in period 2 of task Ⅲ and period 4 of task Ⅰ, somatic discrimination in period 3 of task Ⅱ, attention in period 3 of task Ⅰ, short-term memory in period 3 of task Ⅲ, and decision making in period 4 of all the 3 tasks. A total of 216 task-related neurons were recorded from the frontal cortex while the monkeys were performing the tasks. The incidence of neuronal responses in each period differed in different tasks. The highest incidence was found in periods 3 and 4 of task Ⅰ, period 3 of task Ⅱ and periods 2 and 3 of task Ⅲ,in which the basic intelligence factors were involved. The results indicated that there were neurons in frontal cortex related to discrimination,attention, short-term memory and decision making. The characteristics of the neuronal responses were analyzed. The discriminative function of the frontal neurons was mainly related to the discrimination of the biological meaning of the stimulus rather than its physical attribute. The neurons which were related to short-term memory were also related to attention. The cognitive function of the frontal neurons was established gradually in the course of learning and possessed a high degree of plasticity. Most of the task-related neurons were located in a circumscribed area medial to the superior ramus of the arcuate sulcus in frontal cortex. Cryogenic suppression of this area greatly decreased the abillity to perform the task. Thus, this area of the frontal cortex might play an important role in intellectual behaviors.
出处
《航天医学与医学工程》
CAS
CSCD
1991年第3期157-169,共13页
Space Medicine & Medical Engineering
关键词
智力
神经元
航天
医学
皮层
intelligence, neurons, frontal lobe, cortex, behavior, task, monkey
