Pies: A dog's nose is so sensitive that they can detect changes in a person's emotional state

Evidence: 64 • authority: 72

The dog sense of smell is the most powerful sense of this species, the olfactory system of canines being much more complex and developed than that of humans. It is believed to be up to 10 million times as sensitive as a human's in specialized breeds. Dogs have roughly forty times more smell-sensitive receptors than humans, ranging from about 125 million to nearly 300 million in some dog breeds, such as bloodhounds. These receptors are spread over an area about the size of a pocket handkerchief (compared to 5 million over an area the size of a postage stamp for humans). Dogs' sense of smell also includes the use of the vomeronasal organ, which is used primarily for social interactions. The d…

Evidence: — • authority: 80

The dog nose “KNOWS” fear: Asymmetric nostril use during sniffing at canine and human emotional stimuli

Evidence: — • authority: 72

Fear is an emotional state which is aroused by threatening situations. It is usually considered to be a negative, unpleasant emotion. The feeling of fear can result directly from certain kinds of sensory stimulation, such as sounds which resemble screaming. Fear can also be evoked by the anticipation that undesirable events will, or may, occur, and is useful in providing motivation to avoid or mitigate risks. It may also be the result of imagining threats to oneself or others, whether or not those threats are real or possible. Fear is associated with a number of physiological states. In humans, fear is correlated with more rapid breathing and heart rate, dilation of the pupils, spikes in co…

Evidence: — • authority: 92

Dogs display context-dependent behavioral responses to subtle owner-derived multimodal stimuli.. Introduction Dogs ( Canis familiaris ) can discriminate explicit human emotions using various sensory modalities. However, their sensitivity to subtle human-derived emotional cues accompanied by physiological changes, but lacking clear behavioral cues, remains poorly understood. This study investigated whether dogs could perceive owner-derived emotional cues when suppressing explicit expressions. Methods Owners were assigned to either stress or relaxation conditions designed to induce stress or relaxation, respectively. Following the experimental manipulation, facial video, voice, and olfactory…

Evidence: — • authority: 92

Predicting missed alerts in detection dogs.. Detection dogs are widely used in tasks ranging from explosives detection to medical diagnostics. Yet even well-trained dogs occasionally fail to indicate target odors. Such missed alerts can have severe operational consequences. Here we show that missed alerts are preceded by measurable changes in the dog's behavioral and physiological state. Using a controlled olfacto-treadmill system with precisely timed odor presentation, we analyzed movement dynamics and physiological signals during the seconds preceding each trial. A machine learning model trained on pre-odor movement patterns predicted subsequent missed indications with above-chance accura…

Evidence: — • authority: 38