[New criteria for positron emission tomographic diagnosis of brain glioma using 11C-methionine]. / Novye kriterii v positronno-émissionno-tomograficheskoi diagnostike gliom golovnogo mozga s ispol'zovaniem 11C-metionina.

The study was based on the data of positron emission tomography (PET) and L-[methyl]-[11C]-methionine used in 117 patients with suspected brain tumor. PET data on 74 patients with histologically verified cerebral tumors were analyzed in detail. New additional criteria for assessing PET scans, which formed the PET syndromes of astrocytomas, anaplastic astrocytomas, and glioblastomas. Operative and histological verification confirmed the high validity of the proposed criteria for defining the type of a tumor.

A study of the connectedness among distant neuronal populations in the human brain during mental activity.

In this article, we present the results of a study of connectedness among distant neuronal populations in human deep-brain structures. The time characteristics involved and the stability of the connections between different neuronal populations during monotonous mental activity are discussed. We show that a stable connectedness does correlate with mental activity; however, the connections themselves do not correlate with one another. We also show that the individual connections, the elements of the system which make mental activity possible, can function with various degrees of rigidity or flexibility.

[Relationships of distantly located neuronal populations in the human brain in the realization of the thinking process]. / Issledovanie sviazannosti distantno raspolozhennykh neironakh populiatsii golovnogo mozga cheloveka pri realizatsii myslitel'noi deiatel'nosti.

The time characteristics of the interneuronal connections as well as interrelationships among distant neuronal populations of the human brain deep structures were studied during monotonous mental activity. It was shown that stable interrelationships could be considered as a correlate of mental activity though the connections themselves were not of the correlative nature. These connections, being the elements of the activity--maintaining system, could be of various degree of rigidity.