摘要:

The relationships between two brain stem regions where electrical stimulation (ESB) evokes repetitive vocalizations in birds were investigated in anesthetized chickens. Electrodes were placed in the midbrain call region (MCR) and in a region ventral to nucleus ovoidalis (OM) and checked for ESB-evoked calling. Then radio-frequency lesions were made in MCR and the OM site retested for evoked vocalizations. Lesions in MCR abolished calls evoked from OM indicating that OM excitation produces calls via ipsilateral MCR.

ISSN:0006-8977    

DOI:10.1159/000123651

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The volumes of the acoustic nuclei of 19 speciesof Chiroptera belonging to 8 families have been compared with those of the basal insectivores by aid of the allometry formula. The progression indices have been used giving a direct numerical estimate of how many times a given brain structure of a certain species is larger than the corresponding structure of a basal insectivore of the same body weight.The acoustic nuclei (except the dorsal cochlear nucleus and the medial geniculate body) of the Megachiroptera have very low progression indices which never surpass 200 and fall in the range of variation of the indices of the basal insectivores.Microchiroptera have, in general, a much better developed acoustic system. The relationship between the degree of development of the acoustic nuclei and the feeding habits as well as echolocative skills has been discussed. Fish-eating Noctilio leporinus has the highest progression indices except in the case of the dorsal cochlear nucleus and the medial nucleus of the trapezoid body. Insect-eating bats have a very well developed auditory system but there is a great range of variation within this group which is probably related to the sonar type used and other behavioral adaptations. Within the group of Phyllostomatids the nectarivore Glossophaga soricina has, in general, better developed auditory structures than the frugivorous species. The sanguivore Desmodus rotundus falls within the range of Phyllostomatids except for the medial geniculate body.The dorsal cochlear nucleus is the most progressive structure among Megachiroptera, while its progression index is the weakest among Microchiroptera. The range of variation of the anterior ventral cochlear nucleus is much greater than that of the posterior ventral cochlear nucleus. The medial nucleus of the trapezoid body has a higher index among insect-eating bats than among the other dietary types. The development may be related to the necessity for localization of a moving target. The index of the medial geniculate body is relatively high among all Microchiroptera but there is a remarkable hypertrophy of this structure among Noctilio and Desmodus.The hypothesis is put forth that the differential development of the acoustic nuclei is related to the frequency band width used in echolocation as well as to the capacity of sound discrimination.

ISSN:0006-8977    

DOI:10.1159/000123652

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The volumes of the acoustic nuclei of 19 species of Chiroptera belonging to 8 families have been compared with those of the basal insectivores by aid of the allometry formula. The progression indices have been used giving a direct numerical estimate of how many times a given brain structure of a certain species is larger than the corresponding structure of a basal insectivore of the same body weight.The acoustic nuclei (except the dorsal cochlear nucleus and the medial geniculate body) of the Megachiroptera have very low progression indices which never surpass 200 and fall in the range of variation of the indices of the basal insectivores.Microchiroptera have, in general, a much better developed acoustic system. The relationship between the degree of development of the acoustic nuclei and the feeding habits as well as echolocative skills has been discussed. Fish-eating Noctilio leporinus has the highest progression indices except in the case of the dorsal cochlear nucleus and the medial nucleus of the trapezoid body. Insect-eating bats have a very well developed auditory system but there is a great range of variation within this group which is probably related to the sonar type used and other behavioral adaptations. Within the group of Phyllostomatids the nectarivore Glossophaga soricina has, in general, better developed auditory structures than the frugivorous species. The sanguivore Desmodus rotundus falls within the range of Phyllostomatids except for the medial geniculate body.The dorsal cochlear nucleus is the most progressive structure among Megachiroptera, while its progression index is the weakest among Microchiroptera. The range of variation of the anterior ventral cochlear nucleus is much greater than that of the posterior ventral cochlear nucleus. The medial nucleus of the trapezoid body has a higher index among insect-eating bats than among the other dietary types. The development may be related to the necessity for localization of a moving target. The index of the medial geniculate body is relatively high among all Microchiroptera but there is a remarkable hypertrophy of this structure among Noctilio and Desmodus.The hypothesis is put forth that the differential development of the acoustic nuclei is related to the frequency band width used in echolocation as well as to the capacity of sound discrimination.

ISSN:0006-8977    

DOI:10.1159/000123653

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The midbrain area of the acoustico-lateral lemniscus, ganglion isthmi and medial torus semicircularis was electrically stimulated in free-swimming toadfish. Grunts (threat sounds) and boatwhistles (probable courtship calls) were evoked in both sexes during stimulation of this region, which has been termed the sonic midbrain area (SMA). Several locomotor and defensive responses were elicited with sound production; however, neither complete reproductive nor aggressive patterns were observed. Several points adjacent to the SMA were negative for sound production. It is postulated that the SMA integrates various sensory and hormonal stimuli and controls sound production through connections to lower sonic motor mechanisms.

ISSN:0006-8977    

DOI:10.1159/000123654

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Vigilance is an important facet of animal life andparticularly so in relation to three areas: external danger, the exploitation of environmental resources, and intraspecific communication. The second of these involves, in addition to vigilance, an active search of the environment. The organization of the nervous system, however, imposes certain limitations on the effectiveness of vigilance and these are described, with particular reference to experimental studies of vigilance in man. Three types of strategy are then described which function to offset the neural limitations on vigilance. These are: neural mechanisms, individual behavioural strategies, and social strategies. These are considered in relation to those areas of life already defined as requiring a watchkeeping function.

ISSN:0006-8977    

DOI:10.1159/000123655

出版商:S. Karger AG    

年代:1974

数据来源: Karger

ISSN:0006-8977    

DOI:10.1159/000123656

出版商:S. Karger AG    

年代:1974

数据来源: Karger