1. The Itch
The skin is the only organ that is constantly exposed to possibly irritation. The most common stimuli is dryness associated with the atmosphere or over-washing which removes a quantity of the skins natural oils and moisture.
When you scratch an itch, the 'itch signal' being sent to your brain is interrupted and therefore no longer recognised. Even if the irritant is not fully removed, scratching somewhat diverts attention away from the itch.
Goosebumps are associated with a drop in temperature, fear and other strong emotions. The reflex that causes the phenomena is known as horripilation which involves individual muscles at the base of each hair contracting which in turn makes the hairs on the skin stand up.
Research also suggests that goosebumps are hard to control and may prove a strong indication of true feelings. In other words, scientists can use the phenomena as an indicator of when someone is telling the truth or not.
3. Wrinkled Fingertips
The wrinkling of fingertips is common after a person has been exposed to water for a long period of time. However, fingers don't stay wrinkled for long and soon turn back to normal.
The skin has three layers: i) the subcutaneous tissue - fats, nerves and large blood vessels; ii) the dermis - small blood vessels, nerves, hair roots and sweat glands and; iii) the epidermis - keeps water inside the body from evaporating.
Biologists have found that when skin is submerged in water for a long period of time, the epidermis begins absorbing it. The epidermis is tightly connected to the dermis underneath it and the skin therefore distorts resulting in wrinkles.
Hiccups are often linked to drinking/eating to quickly and consuming alcohol. They are triggered by uncontrolled impulses of the phrenic nerve which cause the diaphragm to spasm. The spasms result in a sharp intake of breath; the hiccup.
Possible cures include holding your breath, eating peanut butter, getting someone to unexpectedly scare you and drinking upside down.
5. Seeing 'Stars'
This can occur after lifting your head up too quickly or being hit in the head etc. The 'stars' are part of a group known as nonphotic visual stimuli and are called photopsia or phosphenes.
The eyeball fluid, which is contained in a sac-like mechanism, begins to pull away from the back of the eye. This process is known as 'posterior vitreous detachment' and makes vision temporarily blurred and distorted.