Technology Effects On Sleep

The Effects of Technology on Sleep

As a result of the invention of electricity and the light bulb, humans are no longer restricted to activity during daylight hours. Modern advancements in technology have been beneficial to productivity, while also leading to a decline in sleep duration. The interactions between sleep and technology have grown more pronounced over the decades, with 90% of Americans reporting to use of some type of electronics within an hour of going to bed (Chang, Aeschbach, Duffy, & Czeisler, 2014). Many aspects of technology usage should be considered when studying their effect on sleep, including visual stimuli (such as light exposure), auditory stimuli (such as music), and the less obvious effects of electromagnetic fields

A review by Hamblin and Wood (2002) found that the most consistent finding from EMF sleep studies was the enhancement of EEG power in the alpha range. Several studies have reported a direct correlation between EMF exposure during sleep and increased power in non-REM (NREM) and stage two sleep in the spindle frequencies (Schmid et al., 2012; Huber et al., 2002). Multiple studies have reported that EMF has effects on the human brain both during and long after the initial exposure (Hamblin & Wood, 2002; Schmid et al., 2012). Huber et al. (2003) reported significantly reduced WASO time after EMF exposure. Many studies before and after this occurrence, however, found no significant effects of EMF exposure on sleep architecture (Huber et al., 2002, Schmid et al., 2012). Huber et al. (2002) reported increased cerebral blood flow in the dorsolateral prefrontal cortex as a result of EMF exposure. A subsequent study, however, found that effects on brain activity were not specific to the site of exposure, which lead the authors to hypothesize that subcortical structures (specifically the thalamus, which is responsible for sleep spindle occurrences) are involved (Huber et al.,

Melatonin suppression is the most common effect of light exposure associated with sleep. Cajochen, Zeitzer, Czeisler, and Dijk (2000) reported that slow eye movements (SEMS), EEG theta-alpha activity, and subjective measures of alertness are all highly correlated with the degree of melatonin suppression. Cajochen, Krauchi, Danilenko, and Wirz-Justice (1998) reported that sleep latency was significantly prolonged after light exposure and reduced after exogenous melatonin administration. Similarly, Chang et al. (2014) found that participants in their LE-ebook condition had longer sleep latency and significantly less REM sleep than those in the regular book condition. In contrast to these studies, Heath et al. (2014) reported no significant effects of light on sleep latency, SEMS, or number minutes spent in SWS and REM stages. Past research indicates that the circadian photoreceptive system is distinct from the image forming system, and that even animals with a loss of their visual system show signs of melatonin suppression and phase shifting after exposure to light (Cajochen, 2007; Cajochen et al. 2000). Several studies have also found that non-visual light responses in humans (i.e.: melatonin suppression and circadian phase shifting) are more sensitive to short-wavelength blue light, such as