There are two primary jobs your lab notebooks should do:

1) They should allow you to reconstruct what you did during the experiment.

This means you should record things like amplifier, stimulator settings, and the times at which experiments were done (even if they are also in a computer file).  Index all of your computer files and pages in the notebook, so that you know where they fit in the experiment (write down the file names and the directory in which they are saved).  Try to be organized, so that if you had to reconstruct what you did you could do so easily, without having to blindly search through your lab books. Changes from the lab manual procedures should also be noted, as well as details of how things went not included in the basic procedure.  Make detailed drawings of how your dissection went and where you made your recordings (such as left vs. right side, segment #).  In order to make them detailed, you will need to make them large.  Fill the whole page.

Note times, electrode changes & resistances, saline changes, and anything else that could affect the experiement.
One should use pen, not pencil, so the writing actually reflects what happens during the lab including any false starts or mistakes.  Don’t worry about cross-outs, just make sure everything is clear.

2) They should contain your results and comments on the significance of your results.

Besides just writing down numbers, you should say something about what the numbers mean.  For example, you may have found that action potential latencies in the sciatic nerve decreased when you switched the polarity of the stimulating electrodes from having the positive pole nearer the recording electrodes to having the negative pole nearer the recording electrodes.  Not only should you write down the values for the latencies (use only significant digits), you should say what the result might mean (that the action potential may be generated at a site closer to the negative stimulating electrode).  If you are not sure what a result means, please ask.  Don’t just mechanically work through the lab exercise; think about what you are seeing, and let your lab notebook show that you have given your results some thought.  

3) Graphics.

Use sketches to illustrate your experimental set-up, to show how the dissection works, and to show how your recordings were made.  When using graphics to illustrate data, be sure to label each axis and include units.  When using computer generated graphics, be sure the graph is smaller than your notebook page, and paste or tape it into your notebook without folding it.

Grading:  Each week’s lab notebook will be worth 10 points (100 total points ). 

The first grade will be dropped and won’t count towards the final grade.

Other advice:

Write in the lab notebook as you go along; don’t try to write up the experiments after you’ve done them.  In general, it is better to write more than less.  It is helpful to tape or glue computer printouts and graphics into your notebooks to illustrate results.  Print them small enough that they don't need to be folded.  Tables of contents are unnecessary.
 

modified 8-22-04