It's natural to ask about your being knocked senseless. It would even be good sense, if only there were any way you could be sensible about it under the circumstances. There's probably not much point in asking what knocked you senseless since you couldn't make sense of it. Really, the only thing to do is provide a list of important senses, so you know which ones should come back.
The sense of taste. Without this, there's really no way to be sure whether you're eating something you like or whether you're the victim of an elaborate prank. The simplest way to test whether you still have the sense of taste is calibration: with a trusted friend swap your tongues and try out some agreed-upon meal. Compare notes, and try to not get into the question of whether the color that you perceive when you see something blue is the same thing your friend sees when she or he sees the same blue thing as this will result in unpleasant questions about whether chocolate tastes like chocolate. Those without friends can borrow a tongue from the library, under the multi-media section.
The sense of touch. This is important so that you know when your leg is being attacked from a cat hiding underneath the bed. If you were unable to feel it when your leg was being swatted by a cat who's discovered the glee of striking from this hiding spot, then you would be forced by logic alone to get rid of the bed, and then where would you sleep?
T he sense of scale. This is important in multiple ways. Without the ability to sense scales you might accidentally step onto one, learning just how unpleasant your current weight is. That sort of news is hard to take this early in the century, and it won't get much better come midcentury, or late century. The other way in which it is important is to tell whether things are small and close up or big and far away. Without the sense of scale you might accidentally take a wide footstep and find yourself suddenly ten floors up on top of the building, to the great annoyance of whoever you were walking with. Of course, things are different if you're trying to lose your friend, for example if because you've found a deep incompatibility with a borrowed tongue.
The sense of smell, particularly the feeling that there's some curious odor like an important car part burning right now. Without this sense there's almost no way to detect a curious odor, fleeting, never quite getting strong enough to say with certainty that something's on fire, never quite faint enough to be credibly just the smell of your shoes being warmed by the car's heater. This way, the drive takes on a new exciting edge as you watch the gauges for whatever the dials are supposed to do when there's a fire inside the car. Maybe it should light up a little frowning icon of a fire fighter. Surely the people in the next car over would honk and point if there were a problem. There are no cars there. With this sense, finally, an ordinary drive can be a harrowing, suspenseful affair.
The sense of balance. Without a good sense of balance it's almost impossible to do a professional job composing the layout and design for a newspaper page. The result is newspapers without any particular élan or fresh visual hooks. With diminished abilities to arrange pictures, headlines, and bodies of text in attractive forms people are forced to leave the printed newspaper business and take up web page design, or building hedge mazes where formerly there was just the parking lot.
The sense of sponge. There are sponges all over, but without a sense of them you could end up wandering aimlessly, occasionally being surprised by something moist yet compressible. You can't go around spritzing objects to then test whether they become more compressible, not without having to answer questions from baffled yet damp onlookers.
Should any senses not come back on their own you should replace them from the store. Try aisle four, by the dollar toys.
Trivia: France's prime minister Georges Clemeneau organized the Paris Peace Conference of 1919 to begin on the anniversary of Kaiser Wilhelm I's 1871 coronation as German Emperor. Source: Paris 1919, Margaret MacMillan.
Currently Reading: A World Out Of Time, Larry Niven. My first Niven experience this millennium, certainly, maybe in fifteen years.