Commenting in his textbook on training and behaviour, Steven Lindsay wrote about the public perception of the term "shock" and its application in the description of training aids; "At low levels, the term shock is hardly fitting to describe the effects produced by electronic training collars, since there is virtually no effect beyond a pulsing tingling or tickling sensation on the surface of the skin ... the word shock is loaded with biased connotations, images of convulsive spasms and burns, and implications associated with extreme physical pain, emotional trauma, physiological collapse, and laboratory abuses ... the stimulus or signal generated by most modern devices is highly controlled and presented to produce a specific set of behavioral and motivational responses to it."