History of the physiological analysis of tremor

Edward J. FINE1 and Linda A. LOHR2
1Department of Neurology and 2Robert L. Brown, M.D. History of Medicine Library, State University at Buffalo, New York, USA

Until the publications of William Gowers (WG) in 1886 from England and Fredrick Peterson (FP) in 1889 from America, almost nothing was known about the frequency and physiology of tremors. Gowers attached a metal rod to the tremoring part and positioned the sharpened end to trace a line on a spring motor driven revolving drum with smoke-blackened paper. WG found that alcoholics had an irregular, fine tremor activated by movement with a frequency of 8.1-11 cycles/sec (cps). The tremor of Parkinson disease (PD) was regular, 4-7 cps, appeared at rest, diminished or stopped with movement. WG described the PD tremor as alternating contractions in opposing muscle causing a rhythmical movements of the parts to which they were attached.

FP used an Edwards sphygmograph (EDS), originally designed to record arterial pulses, to record tremor. FP pressed the rubber plunger of the EDS on a tremoring part and the up and down motion was transferred to a fine wire stylus through levers. The stylus wrote on smoke-blackened paper. The paper was advanced by friction rollers at a moderately precise speed, driven by a spring wound motor. FP noted alcoholics had fine, irregular, 8.5-11 cps tremors activated by action. The tremors of delirium tremens were 5.6-6.8 cps, moderate amplitude. FP described PD tremor as appearing at rest and rarely in action, regular, small amplitude, 5.0-5.4 cps coarse waves. WG and FP described hysterical tremors as irregular, small amplitude, 4-9 cps oscillations. FP postulated that cerebral cortex was the center of action for hysterical tremor.

In 1894 FP constructed apparatus to overcome the potential dampening effect of the EDS upon the tremoring part. FP placed a subject's tremoring finger on a mercury filled Marey tambour (MT) that transduced oscillations into fluid waves. A second MT connected to a mercury filled rubber tube transferred the waves to a stylus that moved up and down against the smoked drum of a Ludwig kymograph. A second stylus, driven by an electric motor, marked off seconds precisely. He varied the drum's rotation speed to analyze waves for sub-harmonic frequencies. Tremor of PD had a frequency of 5 cps, and hyperthyroidism of 10 cps. HE found that some PD patients had sub-harmonic tremors.

Mary A.B. Brazier (MB) used a multichannel electroencephalograph with sensitive amplifiers, filters, electrical motors attached to rollers driving the recording paper and ink pens to mark on the paper the pattern of the action potentials from tremoring muscles in 1994-5. MB found that PD tremor consisted of alternating bursts of agonist and antagonist muscles of 4-7 cps and for combat neurosis, the bursts were synchronous, irregular up to 10-12 cps. Shahani and Lefebvre (1978) found that the EMG activity in alcoholic tremor were either synchronous or continuous and ranged from 8 to 12 cps. Thus FP and WG had made valid and prescient observations with simple and rather crude instruments.

We will present brief biographies of FP, WG, and MB and show that modern tremor analysis by electromyography confirms that WG, FP and MB presciently and accurately described the tremors of PD, alcoholism, hysteria and delirium tremens.

Session X -- New Approaches in 19th Century Neurology
Saturday, 16 June 2001, 2:00 pm

Sixth Annual Meeting of the International Society for the History of the Neurosciences (ISHN) and
Eighth Meeting of the European Club for the History of Neurology (ECHN)

Cologne, Germany