HISTOLOGICAL FEATURES OF THE SPINAL CORD ©David B. Fankhauser, Ph.D., Professor of Biology and Chemistry University of Cincinnati Clermont College, Batavia OH 45103
Overview of spinal cord, 25x	This page has been accessed  times since 25 December 2002.  21 January 1992, 3 Jan 1996, 31 Dec '96, 23 Jan. '97, 7 Jan '98, 5 Jan 00, 31 Jan 01	central canal, 400x

The following are instructions for recording brain waves usng relatively primative equipment available to us at the moment.  Even with the age of the equipment, good tracing can be recorded with proper attention to the idiosyncrasies of the equipment and an understanding of the principles involved.

Equipment and supplies (using Thorton Electronics instruments):strip chart recorder (type-462)
isolated preamp (type-410)
EEG amplifier (type-418)
Bio-amplifier/supply (type-400)
BNC cable, 24 inch
lead wire assembly: +, -, and ground
three electrode plates
two rubber straps, 16 and 30 inches
electrode cream (Medi-Trace EKG sol)
 
 

	1. Assemble and pre-set apparatus: Connect amplifier complex by pushing together:    a) preamplifier    b) EEG amplifier   c) Bio-amp/supply
	Connect BNC cable from EEG amplifier output to Strip chart recorder signal input jack.
	Turn off the power in both strip chart recorder and bio-amp/supply, then plug each into a 110 volt line.

Pre-set the initial settings as follows:
 

	2. Plug lead wires into preamp: Check that three lead wires are not tangled, then plug into isolated preamp receptacle labeled "electrodes". Handle with care (do not pull).
	3. Attach ground electrode to wrist: Attach an electrode plate to the end of the 15 inch strap, apply electrolyte cream, and strap snugly to the inside of a wrist, with the thumb screw toward the hand.
	4. Attach two electrodes to scalp: Attach 2 electrode plates to the 30 in. strap, the first at the end, and the second 4-5 inches from the first. Place a drop of electrolyte cream the size of a pea on each. With assistance, part hair on lateral occipital portions of subject's head, 2.5 inches from midline. With thumb screw inferior, press the first electrode so cream smushes into scalp. Hold in place. Part hair on other side of midline, slightly stretching rubber band and smush second electrode into scalp (also with thumb screw inferior). Hold the second in place also. Have assistant gently stretch rubber band around front of head, and attach to first electrode. Make sure it is not too tight.
	5. Connect wires to electrodes: Attach the ground (G) wire to the ankle electrode, tighten with thumb screw. Repeat with the "+" and "" wires on the R and L electrodes on scalp. The wire fittings are fragile, handle with care (DO NOT PULL THE WIRES).
	6. Adjust settings on machine: With subject in a relaxed, comfortable position, change settings to those in the table above:  When you switch the coupling on the recorder to AC, the needle should now be moving up and down. (If no needle movement, check connections and wiggle switches.)     a) Adjust moving pen position to middle of paper.      b) Turn on chart drive.      c) Adjust pen heat so tracing is a thin black line.
	7.  Record beta waves of alert subject: When satisfied with preparations and the quality of the tracings at 5 mm/sec, switch chart speed to 25 mm/sec. These high frequency (15-60 Hz) low amplitude (5-10 mV) waves are beta waves, typical of the alert brain. Switch off chart drive. (This image has beta at the left, alpha at the right)
	8. Record alpha waves of meditating subject: Have subject lie down in dark, close eyes, breath slowly and deeply to relax for several minutes. Set chart drive at 5 mm/sec. Maintain silence. Run for about a minute. Notice the periodic episodes of alpha waves. Alpha waves are low frequency (8-10 Hz) high amplitude (50 mV) waves. When they appear, switch the chart speed to 25 mm/sec. After a minute, without turning off the machine, have subject open eyes and converse, but not move around, press event button to indicate this change in parameters. The EEG pattern should return to the beta pattern.
	9. Illustrate apparatus, label all features used with appropriate numbers. Cut out examples of alpha and beta waves to mount in your notebook (using scotch tape at the edges, not contact paper). Label and discuss characteristics and significance of each type brain wave recorded.

Very rough board notes to introduce brain waves, 2003 (as temporary service to students).  Board 1, board 2.