Transgenic Mouse Models of Alzheimer's Disease: Behavioral Testing and Considerations, KJ Bryan, H Lee, G Perry, MA Smith, and G Casadesus Cued and Contextual Fear Conditioning for Rodents, P Curzon, NR Rustay, and KE Browman Drug Discrimination, R Young Conditioned Place Preference, AJ Prus, JR James, and JA Rosecrans Anxiety-Related Behaviors in Mice, KR Bailey and JN Crawley Behavioral Assessment of Antidepressant Activity in Rodents, V Castagne, P Moser, and RD Porsolt Assessing Attention in Rodents, PJ Bushnell and BJ Strupp The Behavioral Assessment of Sensorimotor Processes in the Mouse: Acoustic Startle, Sensory Gating, Locomotor Activity, Rotarod, and Beam Walking, P Curzon, M Zhang, RJ Radek, and GB Fox Intravenous Drug Self-Administration in Nonhuman Primates, LL Howell and WE Fantegrossi Contextually Induced Drug Seeking During Protracted Abstinence in Rats, JJ Buccafusco and L Shuster Operant Analysis of Fronto-striatal Function in Rodents, MD Dobrossy, S Brooks, R Trueman, PJ Brasted, and SB Dunnett Working Memory: Delayed Response Tasks in Monkeys, JS Rodriguez and MG Paule Spatial Navigation (Water Maze) Tasks, AV Terry, Jr Water Maze Tasks in Mice: Special Reference to Alzheimer's Transgenic Mice, D Morgan Behavioral Neuroscience of Zebrafish, ED Levin and DT Cerutti Caenorhabditis elegans Model for Initial Screening and Mechanistic Evaluation of Potential New Drugs for Aging and Alzheimer's Disease, Y Luo, Y Wu, M Brown, and CD Link The Revival of Scopolamine Reversal for the Assessment of Cognition-Enhancing Drugs, JJ Buccafusco Index

Methods of Behavior Analysis in Neuroscience

The review evaluates thresholds of peripheral nerve stimulation by complex current waveforms. A neuroelectric model employing Frankenhaeuser-Huxley membrane nonlinearities is used to derive excitation thresholds for monophasic and biphasic pulse sequences, as well as sinusoidal stimuli. The model, along with principles of magnetic field induction, is used to derive criteria of acceptability for exposure to time-varying magnetic fields. Applications to pulsed gradient fields from magnetic resonance imaging devices are discussed.

Peripheral nerve stimulation by induced electric currents: exposure to time-varying magnetic fields.

Low-frequency electric currents of a few milliamperes flowing through the body cause muscular contractions. In the arm such an effect may make a subject unable to let go of a live conductor. The highest currents which 99.5 per cent of men and 99.5 percent of women are able to let go have been shown to be 9 and 6 mA, respectively. Currents somewhat larger than this, in the range of 20 to 40 mA, passing across the chest may arrest respiration leading to asphyxia, unconsciousness, and even death.

Reevaluation of Lethal Electric Currents

Since ground fault currents in high-voltage systems are on the increase, the hazards associated with transmission tower voltages during ground faults have become of concern. An analytical method is presented to determine these voltages for long and short lines, arbitrary ground network terminations, and any combination of skywires and counterpoise conductors. The proportion in which the fault current is supplied by the line on both sides of the fault location is taken into account, and the effect of fault currents flowing in parallel external circuits is also considered. The touch and step potentials at the faulted tower are determined and an assessment is given of the hazard they may represent. In a numerical example, several measures aimed at reducing this hazard are compared.

Analysis of Transmission Tower Potentials During Ground Faults

Effects of Electric Shock on Man

A REVIEW of the literature has revealed very little information regarding the effects of small 60-cycle electric currents on man. These currents are not sufficient to produce unconsciousness or death but they are sufficient to produce involuntary muscular contractions. The hazard to the public has been increased because of the recent development and application of electrical devices with exposed electrodes, such as the electric fence, the electric fly panel, the electric insect trap, the electric cattle prod, and the a-c welding apparatus. The fatal accidents that have occurred due to these devices have emphasized the importance of obtaining additional knowledge on electric shock. This report is based on experiments just completed on 120 men. A preliminary investigation had been made during 1936–37 on 56 men.1 Some of the data collected then have been included in the body of this paper, but not in the statistical analysis. It is hoped that the results may help to improve the design and safety of some of the new electrical devices and may be useful in clarifying the widespread misunderstanding of electric shock.

Joe L. Thurston

Papers

Electric Shock