Through the medulla, at the lower end of the brainstem, pass all the nerves running between the spinal cord and the brain in the pyramids of the medulla, many of these nerve tracts for motor signals cross over from one side of the body to the other. This region is also an important junction for the control of deliberate movement. The brainstem, at the top of the spinal cord, controls breathing, the beating of the heart, and the diameter of blood vessels. The hindbrain contains several structures that regulate autonomic functions, which are essential to survival and not under our conscious control.
#THEBRAIN 9 CONTEXT SENSITIVE NAMES SERIES#
The human brain actually has its beginnings, in the four-week-old embryo, as a simple series of bulges at one end of the neural tube.
In the growth of the individual embryo, as well as in evolutionary history, the brain develops roughly from the base of the skull up and outward. Indeed, in strictly biological terms, these structures can claim priority over the cerebral cortex. But underneath this layer reside many other specialized structures that are essential for movement, consciousness, sexuality, the action of our five senses, and more-all equally valuable to human existence. The cortex contains the physical structures responsible for most of what we call ''brainwork": cognition, mental imagery, the highly sophisticated processing of visual information, and the ability to produce and understand language. The preponderance of the cerebral cortex (which, with its supporting structures, makes up approximately 80 percent of the brain's total volume) is actually a recent development in the course of evolution. This schematic image refers mainly to the cerebral cortex, the outermost layer that overlies most of the other brain structures like a fantastically wrinkled tissue wrapped around an orange. We do not experience our brain as an assembly of physical structures (nor would we wish to, perhaps) if we envision it at all, we are likely to see it as a large, rounded walnut, grayish in color. Thus it should not be used on links of any kind, even if the link is to a help page.Outside the specialized world of neuroanatomy and for most of the uses of daily life, the brain is more or less an abstract entity. I'll also just throw in that the behavior of clicking something that is showing this cursor should not navigate away from the current page, because the cursor is primarily an arrow and not a pointing hand. Some web pages will use a double-underline, but that only works for text and even then is hardly common enough to be considered a standard idiom. what things can be pointed at to get help. That said, it's not a commonly-used interface anymore, and most UIs tend to embed the contextual help information into the interface from the beginning, or based on keyboard focus more than mouse focus, since modern touch interfaces don't work well with the idea of pointing at elements of the UI.Īnother problem with this cursor is there is no agreed-upon interface to represent the other side of the equation: i.e. Since the help icon is attached to the cursor, the only logical action should be a click (specifically a left-click), and the click should present help information about whatever the cursor is over. The help is immediately shown along with the cursor (for example in the form of a tool tip), in which case it should be obvious and no action is necessary, or,.Since it is contextual (it has to be, since it's directly attached to the mouse cursor and therefore is representational of whatever the cursor is pointing at), there are essentially two possibilities: As the W3C page says, the cursor means "help is available".