Cool/cold surfaces: Sitting on sidewalks which are cool, leaning on or grabbing a cold pole can result in hives forming on the area which had contact with the cool surfaces. Cold IV lines:  Sometimes IV lines are cold, which can result in a reaction. A line of hives may appear within 6 to 8 inches from the IV site in the pattern of a line going up the limb. Activities:
Cold foods and drinks: Eating or drinking cold or cool substances such as ice cream or iced tea may result in a reaction inside the mouth and throat. Swimming: Swimming can be especially dangerous, as the rapid heart rate combined with the onset of hives can lead to hypotension, shock, and drowning. Sweat: A reaction may even occur on a warm day when there is sweat on the skin, since the reaction is triggered by skin temperature, not core temperature. If there is a breeze, it will rapidly cool the skin and create hives. Restriction of blood flow: Activities which cause tense muscles and reduce blood flow can cool the body parts enough to trigger itching and hives. Drugs
The first-line therapy is symptomatic relief with second-generation H1-antihistamines.
This syndrome might be difficult to distinguish from a bilateral temporal lesion such as described above. Diagnosis
Since cortical deafness and auditory agnosia have many similarities, diagnosing the disorder proves to be difficult. Bilateral lesions near the primary auditory cortex in the temporal lobe are important criteria. Cortical deafness requires demonstration that brainstem auditory responses are
normal, but cortical evoked potentials are impaired. Brainstem auditory evoked potentials (BAEP), also referred to as brainstem auditory evoked responses (BAER) show the neuronal activity in the auditory nerve, cochlear nucleus, superior olive, and inferior colliculus of the brainstem. They typically have a response latency of no more than six milliseconds with an amplitude of approximately one microvolt. The latency of the responses gives critical information: if cortical deafness is applicable, LLR (long-latency responses) are completely abolished and MLR (middle latency responses) are either abolished or significantly impaired. In auditory agnosia, LLRs and MLRs are preserved. Another important aspect of cortical deafness that is often overlooked is that patients feel deaf. They are aware of their inability to hear environmental sounds, non-speech and speech sounds. Patients with auditory agnosia can be unaware of their deficit, and insist that they are not deaf. Verbal deafness and auditory agnosia are disorders of a selective, perceptive and associative nature whereas cortical deafness relies on the anatomic and functional disconnection of the auditory cortex from acoustic impulses. Case examples
Although cortical deafness has very specific parameters of diagnosis, its causes on the other hand can vary tremendously.