A novel method and microprocessor-controlled apparatus are provided for improving research and/or communication interaction between human and animals, such as dolphins and the like, or between normal humans and speech-impaired humans, by playing back audible pre-recorded human-language phrases corresponding to and descriptive of the meaning of sounds and/or gestures or responses produced by the animal or the speech-impaired human and in response to stimuli, conditions or environmental events to which the animal (or impaired human) is subjected, wherein the pre-recorded phrases represent what the human would say or describe if subjected to such stimuli, conditions or environmental events; such that during actual real-time interacting with the animals (or such impaired humans) one actually hears "from" the animal or speech-impaired human, spoken language phrases descriptive of their condition.

A computerized security system which enhances the security provided by watchdogs on a given premises by analyzing the auditory and physiological indications given by the dogs to assess the level of security at any point in time. By attaching sensors to the dogs and placing microphones in their proximity the system continuously collects information about the dogs' auditory and physiological behavior, and according to predetermined parameters it assesses the watchdogs' physiological and emotional state. Having concluded that any of the dogs sense a threat or has been neutralized in any way the system may update the state of security on the users' security terminals. The system determines between three possible security states: no alert when no irregular activity is registered, medium alert if the dogs indicate a state of moderate alertness and high incase there are indications for a definite hostile presence.

A voice connection system comprises a sensor matrix sending to a control unit signals indicating an animal's status in terms of stimuli, feelings, events, actions or behavior of said animal. The control unit selects--depending on the signals received--a voice message recorded into memory means associated to the unit, and activates a loudspeaker belonging to the system, in order to issue said voice message. The system further comprises voice recognition means, which activate pulse generators depending on the content of a voice message uttered by the human user.

A dog bark limiter includes a housing (2) supported against the dog's skin by a strap, stimulus electrodes (5), and a sensor (6) for producing signals in response to vocalizing by the dog. The sensor includes a membrane (6) supported by the surface (9) for efficiently transmitting sound energy through the housing and a rigid nipple (11) engaging the membrane. Control circuitry in the housing has an input coupled to an output of the transducer and output terminals coupled to produce aversive stimulus signals between the first and second electrodes in response to the signals produced in response valid barking by the dog. A motion detector (40) produces a motion detection signal in response to a characteristic movement of the portion of dog that accompanies barking by the dog and aids in detecting a valid bark. A controller (33) executes a frequency capture routine to produce a frequency spectrum of the dog's vocalizations and compares it with a valid bark spectrum to determine if the vocalization constitutes a valid bark.