Androgen plays an important role in singing of songbirds. Recent studies have shown that androgen levels in vivo not only affect the external morphology of songbirds, but also affect their singing behavior. Androgens (including derivatives) affect singing behavior and singing system in many ways. Based mainly on the results from our research group in the zebra finch, this review summarizes the effects of androgen on singing behavior, excitability and synaptic transmission of projection neurons of singing system, and the interaction of androgen with other neurotransmitter receptors in the brain of songbirds.
Androgens ; physiology ; Animals ; Brain ; physiology ; Songbirds ; physiology ; Vocalization, Animal

vocalization differentiation. The classification can be risky as it is sometimes unclear if different types of vocalizations are produced in different environments or if a unique type of vocalization is used with variation in the acoustic parameters. As an example, isolation calls produced by kittens differ depending on the context. The environment has an important impact on the vocal behaviour and thus feral cats and pet cats vocalize differently. Pet cats are thus able to create an efficient communication with humans thanks to the flexibility of vocalisation behaviours. This review allowed us to create a simple model of the cat vocal repertory.]]>
Acoustics ; Animals ; Auditory Perception ; Cats ; Classification ; Humans ; Pliability ; Vocalization, Animal

Animals ; Callithrix ; Sex Factors ; Vocalization, Animal ; Sex Characteristics

Masking therapy can make patients accustom to tinnitus. This therapy is safe and easy to implement, so that it has become a widely used treatment of curing tinnitus. According to surveys of tinnitus sounds, cicada sound is one of the most usual tinnituses. Meanwhile, we have not hitherto found published papers concerning how to synthesize cicada sound and to use it to ameliorate tinnitus. Inspired by the human acoustics theory, we proposed a method to synthesize medical masking sound and to realize the diversity by illustrating the process of synthesizing various cicada sounds. In addition, energy attenuation problem in spectrum shifting process has been successfully solved. Simulation results indicated that the proposed method achieved decent results and would have practical value for the future applications.
Acoustic Stimulation ; Animals ; Computer Simulation ; Hemiptera ; Humans ; Perceptual Masking ; physiology ; Sound ; Tinnitus ; therapy ; Vocalization, Animal

The synaptic connection from high vocal center (HVC) to robust nucleus of the arcopallium (RA) is a pivotal part of vocal motor pathway in songbirds. Electrophysiological properties of HVC-RA synaptic transmission in adult male zebra finch (Taeniopygia guttata) in vivo was investigated by using field potential recording method. Following electrical stimulation of HVC, the evoked field potentials recorded in RA were feeble. The results showed that the remarkable paired-pulse facilitation was induced by paired-pulse stimulation at HVC-RA synapses. The results also showed that the evoked field potentials were significantly decreased after a conditioning tetanic stimulation and finally recovered gradually within 15 min, which indicates tetanic stimulation-induced transient depression is present at HVC-RA synaptic transmission. These results suggest that properties of synaptic transmission in this pathway might play a role in controlling song production.
Animals ; Electrophysiological Phenomena ; physiology ; Evoked Potentials ; Finches ; physiology ; High Vocal Center ; physiology ; Male ; Prosencephalon ; cytology ; physiology ; Synaptic Transmission ; physiology ; Vocalization, Animal ; physiology

OBJECTIVE: To investigate the effect of early scream sound stress on the ability of spatial learning and memory, the levels of norepinephrine (NE) and corticosterone (CORT) in serum, and the morphology of adrenal gland.
 METHODS: Female Sprague-Dawley (SD) rats were treated daily with scream sound from postnatal day 1(P1) for 21 d. Morris water maze was used to measure the spatial learning and memory ability. The levels of serum NE and CORT were determined by radioimmunoassay. Adrenal gland of SD rats was collected and fixed in formalin, and then embedded with paraffin. The morphology of adrenal gland was observed by HE staining.
 RESULTS: Exposure to early scream sound decreased latency of escape and increased times to cross the platform in Morris water maze test (P<0.05). The levels of serum NE was significantly elevated, with an obvious tendency in the increase of CORT level (P<0.05). The morphology of adrenal gland was also influenced. 
 CONCLUSION Newborn female rats subjected to scream sound stress can enhance spatial learning and memory ability in adulthood, which is related to activation of the hypothalamo-pituitary-adrenal axis and sympathetic nervous system.
Adrenal Glands ; anatomy & histology ; Animals ; Corticosterone ; blood ; Female ; Maze Learning ; Memory ; Norepinephrine ; blood ; Psychoacoustics ; Rats ; Rats, Sprague-Dawley ; Stress, Psychological ; Vocalization, Animal