Question

1. Why is REM sleep called “paradoxical sleep”? In your answer, describe 3 reasons why REM is “paradoxical”. Then describe one theory as to the purpose of REM sleep.

2. Why does pair-bond behavior in prairie voles differ from that in montane or meadow voles? In your answer, describe how these two types of voles differ in their pair-bond behavior and describe the roles of oxytocin and vasopressin in these behaviors.

Answer 1

1. Why is REM sleep called “paradoxical sleep”? In your answer, describe 3 reasons why REM is “paradoxical”. Then describe one theory as to the purpose of REM sleep.

R.E.M. sleep is referred to as paradoxical sleep since it has similarities to the wakeful state. In this state, though the body remains paralysed, the brain would act un a manner that is similar to being awake, such that cerebral neurons will also be firing with the intensity that is similar in overall impact to the state of wakefulness. There is rapid movement of eyes which would be moving in quick fashion in a back and forth manner. There is quickening of pulse and breathing. Though the status of mind is similar to that being awake, the brainstem carries our blockage of muscle movements. The purpose of the R.E.M. sleep is that people can dream in that phase of their sleep. It was hypothesised by Francis Crick that dreams would be acting a the “unlearning” machine. Also, certain neural activity modes would be erased as there occur random cortical connection activation.

2. Why does pair-bond behavior in prairie voles differ from that in montane or meadow voles? In your answer, describe how these two types of voles differ in their pair-bond behavior and describe the roles of oxytocin and vasopressin in these behaviors.

Prairie voles are notable animal models that are used for studying the monogamous behavior of social bonding as male as well as femal partners would be forming pair bonds that last life long, groom, huddle each other, would be sharing nests and raising pups with responsibilities and would be showing a high affiliative behavior level. Moreover, for the prairie voles, because when there is vasopressin, the prairie voles do not exhibit aggression towards female partners, but against other male partners and strive to take care of the female partner. This is not seen in meadow voles, as monogamous pair bonds are not seen.