Facial composite In the U.S. the FBI maintains that hand-drawing is its preferred method for constructing a facial composite. Many other police agencies, however, use software, since suitable artistic talent is often not available. Until quite recently, the facial composite systems used by international police forces were exclusively based on a construction methodology in which individual facial features (eyes, nose, mouth, eyebrows, etc.) are selected one at a time from a large database and then electronically 'overlaid' to make the composite image. Such systems are often referred to as feature-based since they essentially rely on the selection of individual features in isolation.
Facial feedback hypothesis muscle feedback by blocking presynaptic acetylcholine receptors at the neuromuscular junction. Thus, while motor efference commands to the facial muscles remain intact, sensory afference from extrafusal muscle fibers, and possibly intrafusal muscle fibers, is diminished. Several studies have examined the correlation of botox injections and emotion and these suggest that the toxin could be used as a treatment for depression. Further studies have used experimental control to test the hypothesis that botox affects aspects of emotional processing. It has been suggested that the treatment of nasal muscles would reduce the ability of the person to form a disgust response which