Added on - 20 Nov 2019
To what extent is the state instability hypothesis supported by the study?The hypothesis postulates that state instability is associated with an increase in sleepdrive and it leads to variable neurobehavioral performances. The research study largelysupports the hypothesis. This study illustrated differences between neural activation duringlapses in sleep deprivation and lapses after a normal night’s sleep. Brain imaging studies ofthe participants showed that sleep deprivation resulted in less accuracy and more variabilityin the performance. A prominent long right tail was observed after SD in correct trial’sdistribution of response. Task related activation was found to be reduced in SD in comparisonto rested wakefulness. The reduction in peak signal was comparatively small between thedifferences in peak signals induced by such lapses in both the states. Increased peak signals incognition control regions were associated with SD lapses. This elevation was less pronouncedin SD compared to RW. RW lapses in inferior occipital regions showed no relation to peaksignals. However, in SD they were found to be linked to a reduction in extrastriate peaksignals. On comparing cortical responses, greater bilateral intraparietal sulcus and medialfrontal peak signals were found to be correlate with slow reponses. Fastest responses failed tocreate higher activation in the extrastriate visual cortex region. Thus, the study found that SDattenuated activation in brain during lapses in addition to affecting the overall activationpatterns related to tasks. These findings helped in differentiating SD lapse from other lapsesthat occur after a normal sleep. Thus, the findings were completely in line with the theory ofstate instability.