Methods in Psychobiology

Specialized Laboratory Techniques in Neuropsychology and Neurobiology

R. D. Myers

• Publisher: Academic Press
• Year: 2013
• ISBN:
  9781483268293
• Topic: Biological Sciences
• Subtopic: Neuroscience
• Index: Biological Sciences

Methods in Psychobiology, Volume 2, Specialized Laboratory Techniques in Neuropsychology and Neurobiology is intended for the beginning ""student"" in physiological, neuro-, bio-psychology, or whatever label one wishes to attach to the exciting interdisciplinary field which weds the brain and behavior. In contrast to Volume 1, somewhat more emphasis is given in the selection of topics to a number of difficult behavioral methods that are used frequently by individuals in the more traditional neurosciences. The book begins with a discussion of the measurement of behavioral activity. This is followed by separate chapters on techniques such as electric shock motivation; aversive learning; methods of assessing the behavioral effects of drugs; long-term intravenous infusions; and perfusion of different parts of the brain. Subsequent chapters deal with the assay of pharmacologically active substances; the split-brain technique; using microknives in brain lesion studies and the production of isolated brain-stem islands; the functional decortication technique; and recording evoked potentials.

Chapter 1

Measuring Behavioral Activity

FRANK W. FINGER, Department of Psychology, Gilmer Hall, University of Virginia, Charlottesville, Virginia, U.S.A.

Publisher Summary

This chapter discusses the belief that electro, neuro, and physiological sophistication may be wasted unless the subtleties on the measurement end of the enterprise are to a degree recognized. The measures of general behavioral activity can be so distorted by irrelevant variables that they are sometimes of questionable value. A few simple precautions need to be taken by the experimenter to sufficiently reduce the variability to have a powerful tool for the assessment of the neurophysiological state. There is still the effect upon one’s results of the type of measuring device and the uncertainty of how this may best be dealt with. For testing the effect of brain interference, the running wheel seems a logical choice in view of its mechanical simplicity and the demonstrated sensitivity of running to physiological and environmental manipulations. The chapter discusses the recording techniques that are similar in that the animal lives in an enclosure much like a standard home cage. Various shapes and sizes are used with the average dimension perhaps two or three times the body length. More than is the case with the wheel, these methods have been readily adapted to species other than the rat.

I. Introduction

II. Methods of Measurement

III. The Revolving Wheel

A. Characteristics of the Wheel

B. The Measurement Period and Habituation

C. Individual Differences

D. Long-range Changes

E. Environmental Control

F. Use of Side Cage

G. Recording

IV. Stabilimeter and Stationary-cage Recording

A. General Characteristics

B. Stabiiimeters and Tilt Cages

C. Photoelectric Recording

D. Ultrasonic Recording and Resonant Circuits

E. Direct Observation

V. Conclusions

Acknowledgement

References

Appendix

I INTRODUCTION

A QUICK glance at the chapter headings in these volumes suggests a greater emphasis on “neuro-” than upon “-psychology.” There is no doubt that the prospective experimenter will welcome the chapters of detailed instructions in the manipulation of the independent variable, involving as it does a relatively inaccessible and somewhat mysterious mass of tissue and drawing upon several disciplines for its specialized techniques. By contrast, the reliable recording of the consequent behavior changes usually seems pretty straightforward and routine, demanding little more than a modicum of common sense, an equipment catalogue, and a modest grant. At the gross level this may be adequate. It is sometimes obvious that the brain-operated animal eats nothing, that his bar-pressing for water is insufficient to keep him alive, that his learning is retarded, or that he is incapable of coordinated locomotion on a flat surface.

But as extirpation-by-teaspoon is replaced by functional ablation, stereotaxic localization, and microdissection, it is also appropriate to advance to a more fine-grained analysis of the dependent variable. This chapter, as well as Chapter 10 in Volume I of this series and Chapters 2, 3 and 4 in this volume, is predicated on the belief that electro/neuro/physiological sophistication may be wasted unless the subtleties on the measurement end of the enterprise are to a degree recognized.

Long a favorite behavioral target of the psychopharmacologist, general activity has in recent years been increasingly adopted as an assay tool by neuropsychologists. A change in activity level can indeed be a sensitive indicant of an altered internal state (motivation?), but its maximal usefulness requires attention to a number of potentially distorting factors. Failure to take these into account has led in many instances to unnecessary variability of the data, and on occasion, to conclusions that seemingly contradict each other. The identification of some of these pitfalls will be the major goal of the pages that follow.

In terms of its operational definition, and I question the present utility of any other, “general activity” must be regarded as multiple rather than unitary, and the first lesson to be heeded is that the differently measured general activities may diverge under identical biological conditions. Thus, the amount of the rat’s wheel running during the third day of continuous water deprivation is usually several times the ad lib. base-line (Finger and Reid, 1952), but measurement in a stabilimeter may yield no significant change, or even a decreased count (Campbell, 1964). The 4- or 5-day estrous cycle of activity is much more clearly revealed by wheel recording than by photocell recording or direct observation of the female rat’s movements about the home cage (Finger, 1961, 1969). Telencephalic lesions differentially affect activity in wheel and stabilimeter (Campbell and Lynch, 1969), and there is evidence that the behaviors reflected in the contrasting scores are mediated by different pathways (Lynch, 1970).

Clearly it is inappropriate, in enumerating the consequences of a neurological manipulation, to refer simply to a change or lack of change in general activity, without specifying the method of measurement. The specification of the situation must extend to the physiological and environmental conditions, for complex interactions seem to be the rule rather than the exception. To illustrate: hunger greatly accentuates the difference between frontal rats and controls in the stabilimeter, but not in the wheel (Campbell and Lynch, 1969), and deep frontal lesions elevate stabilimeter scores much more in the light than in the dark, but only during the first few postoperative days (Harrell and Isaac, 1969). As one examines in detail the major types of activity measurement, the suspicion is born that any neurological intervention can be shown to produce a change under some combination of circumstances. A dubious dividend is the limitation which such rich diversity imposes upon interpretation.

II METHODS OF MEASUREMENT

Any listing of methods that attempts to be both inclusive and restrictive would be an exercise in arbitrariness. It might be argued that the common label should be applied only to those procedures that yield similar results under comparable conditions, but at this point, the data required for such a classification are still fragmentary. In deciding which methods to describe, I have simply accepted the investigator’s statement that what he is measuring can legitimately be termed general activity.

As a guide for the experimenter’s minimal coverage of the possibilities, it may tentatively be hypothesized that the revolving wheel or drum as normally used is in a category by itself, with all the other techniques in a second group. But even this prescription, it must be acknowledged, cannot yet be generalized beyond the rat. Further, there i...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• LIST OF CONTRIBUTORS
• PREFACE
• Chapter 1: Measuring Behavioral Activity
• Chapter 2: Techniques of Electric Shock Motivation
• Chapter 3: Aversive Learning Situations: Apparatus and Procedures
• Chapter 4: Assessing the Effects of Drugs
• Chapter 5: Manipulation of the Oral and Gastric Environments
• Chapter 6: Long-term Intravenous Infusion
• Chapter 7: Methods for Perfusing Different Structures of the Brain
• Chapter 8: The Neurobiological Assay
• Chapter 9: Specialized Lesions: The Split-Brain Technique
• Chapter 10: Specialized Lesions: “Cerveau Isolé” and “Encephale Isolé”
• Chapter 11: The Use of Microknives in Brain Lesion Studies and the Production of Isolated Brain-stem Islands
• Chapter 12: Inducing Cortical Spreading Depression
• Chapter 13: Recording Evoked Potentials
• AUTHOR INDEX
• SUBJECT INDEX