CHAPTER 5 Experimental Enclosures and Physical Restraint 53 
Types of Apparatus 53 
Considerations 54 
References 55 
CHAPTER 6 Pharmacological Studies 57 
Behavioral Baselines 57 
Considerations Related to Housing and Social Grouping 58 
Pharmacological Variables 59 
Dose-Effect Relationships 59 
Drug Vehicles 59 
Route of Administration 60 
Health Considerations 62 
Drug Side Effect 62 
Physical Dependence 62 
Duration of Drug or Toxicant Exposure 63 
Long-Lasting Drug Effects 63 
References 63 
CHAPTER 7 Aversive Stimuli 67 
Aversively Motivated Behavior 67 
Electric Shock 69 
Stress Research 69 
Pain Research 70 
Pain Assessment Methods 71 
Chronic Pain Models 73 
Other Considerations 73 
Conclusion 74 
References 74 
CHAPTER 8 Social Variables 79 
Social Variables as Research Topics 79 
Population Density 79 
Group Formation and Intruder Paradigms 80 
Social Separation or Isolation 80 
Social Deprivation 80 
Behavioral Implications of Manipulating Social Variables . 81 
Sociability of the Species 81 
Group Formation and Intruder Paradigms 81 
Gender of the Animal 82 
Age of the Animal 82 
Type of Social Partner 82 
Resource Availability 82 
Separation from the Social Group 83 
Mother-Infant Rearing 84 
Social Manipulations: Exposure to Unfamiliar Animals 84 
Mixed Species Interactions 84 
Separation from Conspecifics During Development 85 
Nonhuman Primates in Social Research 86 
Conspecific 86 
Peer Rearing 86 
2 
