Showing papers on "Temporal cortex published in 1970"

Cerebral representation of vocalization in the squirrel monkey.

Abstract: Specific vocalization types following electrical stimulation of 5940 electrode positions are studied in 39 squirrel monkeys. Except cerebellum, caudal medulla, and a few cortical areas, the sites of stimulation were distributed throughout the brain. Each vocalization elicited was tested for reproducibility at the site of stimulation and in homologue structures. All vocalizations were analyzed spectrographically and then classified for eight fundamental vocalization types. The cerebral distribution of two call types forms continuous systems extending from midbrain via diencephalon into forebrain; the remaining call types are represented in several separate areas not continuous with each other. In medulla and pons the responsive substrates for vocalization follow the course of the spinothalamic tract; in midbrain they lie within the periaqueductal gray, lateral tegmentum, and lemniscus medialis; in diencephalon they are found in the hypothalamus and midline thalamus; in forebrain, finally they are distributed over amygdala, stria terminalis, substantia innominata, preoptic region, septum, rostral hippocampus, posteromedial orbital cortex, cingulate gyrus, and rostroventral temporal cortex. Hence a close relation between limbic system and vocalization producing substrates emerges. Among the brain structures yielding vocalization the mesencephalic periaqueductal gray is assumed to be the region where the electrical stimulus interferes most directly with specific vocalization mechanisms. Besides the anatomical site of stimulation the set of stimulus parameters is important for the elicitation of vocalizations. Relations between amplitude, frequency, and duration of impulses on the one hand and type, loudness, rhythm, duration, and latency of vocalization on the other hand were tested. The influence of the stimulus set on the reaction parameters depends also on the relative position of the electrode within the effective structure. Proper manipulation of stimulus parameters often results in the disintegration of a complex stimulus response into single components.

Distribution of antidiuretic substance in the diencephalon and mesencephalon of the dog.

Abstract: Antidiuretic (AD) activity was studied in the following regions of the dog brain: hypophysis (1); supraoptic and preoptic areas (2); medio-ventral hypothalamus (3); medio-dorsal hypothalamus and anterior thalamus (4); posterior thalamus (5); mammillary area (6); mesencephalon (7); temporal cortex (8); and caudate nuclei (9). AD activity was found in the samples derived from the hypophysis, hypothalamus, thalamus, and mesencephalon (brain region 1 to 7), while samples of the temporal cortex (8) and the caudate nuclei (9) showed no activity. The AD activity present in the hypophysis (1) and in ventral hypothalamic regions (2, 3 and 6) was due to the substance(s) whose activity was dependent upon an intact disulphide bond, mainly vasopressin. The AD activity in the thalamus (5) and in the mesencephalon (7) was only partially dependent on the vasopressin content.

Comparative observations on the epileptogenesis. Experimental investigation in kittens.

Abstract: The paper reports on the results of a series of investigations carried out in kittens of exactly known age and a comparison with results obtained in adult cats. The stimulation included neuro-physiological, clinical-behaviour and pharmacological methods; electrical stimulations as well as chronic irritative lesions of the brain evoked by means of aluminium hydroxide. A comparison of the somato-motor and temporal cortex confirmed the expected clear-cut differences between foci of these regions regarding the onset and type of seizures. These results may be due to maturative factors and differences in the excitability of the brain regions examined. The value of various experimental techniques is discussed. Future experimental projects are mentioned and peculiar behaviour- and seizure patterns pointed out.