Birthing Consciousness as a Case of Adaptive Altered State of Consciousness Associated With Transient Hypofrontality

Abstract

In this article, I present the concept of “birthing consciousness,” a psychophysical altered state of women that can occur during natural and undisturbed birth. I demonstrate that this altered state of consciousness (ASC) has phenomenological and cognitive features of hypofrontality; thus, birthing consciousness probably shares a similar brain mechanism to that postulated by the transient-hypofrontality theory (THT). I argue that until recently (with the advent of modern medical intervention), in evolutionary terms, women lacking the proclivity for this specific brain mechanism had a lower chance of reproducing successfully. Hence, I suggest a general and preliminary hypothesis concerning THT: Birthing consciousness is one example of an adaptive pain-induced ASC associated with transient hypofrontality.

Keywords

evolutionary psychology transient-hypofrontality theory natural birth altered state of consciousness birthing consciousness

Consciousness-altering behavior is well recognized as a universal phenomenon (Blackmore, 2017; Dietrich, 2003; Dietrich & Al-Shawaf, 2018; Furst, 1977; Siegel, 2005; Weil, 1972). Dietrich and Al-Shawaf (2018) reviewed the neuroscientific and psychological evidence substantiating the transient-hypofrontality theory (THT), which postulates that some alterations to consciousness involve the progressive down-regulation of brain networks supporting the highest cognitive capacities. The down-regulation follows the functional hierarchy, one phenomenological subtraction at a time, to those supporting more basic functions. According to the theory, many altered states of consciousness (ASCs), such as dreaming, daydreaming, some types of meditation, certain drug states, runner’s high, and hypnosis, are due principally to a transient state of hypoactivity of various depths and extents in networks of the prefrontal cortex. Given the universality of ASCs, and the fact that consciousness-altering behavior is not unique to humans (Siegel, 2005), Dietrich and Al-Shawaf (2018) examined why this general brain mechanism of hypofrontality might have evolved and suggested that such a ubiquitous phenomenon may require an evolutionary explanation.

In the search for an evolutionary explanation for transient hypofrontality, I suggest examination of an ASC that has not been discussed previously in relation to THT: the psychophysical altered state of women that can occur during natural and undisturbed birth, an ASC that I call birthing consciousness. In this article, I present empirical findings—primarily phenomenological and cognitive—supporting the similarity between characteristics of this ASC and those postulated by THT. I then propose that birthing consciousness is an example of an adaptive, pain-induced, altered state of consciousness associated with transient hypofrontality: Because successful natural birth for the mother and for her baby was essential to reproduction throughout most of human history, and because natural birth is an experience of extreme pain and the transient-hypofrontality brain mechanism correlates with pain reduction, among other phenomenological and cognitive features that ameliorate birthing, the unique ASC that I refer to as birthing consciousness increases the probability for optimal birth outcomes.

Furthermore, I briefly discuss the following derivative idea: Because consciousness-altering behavior is not unique to humans, it is possible that natural birth benefits from a more ancient pain-induced ASC adaptation occurring long before Homo sapiens walked upright, making natural childbirth much trickier.¹ Examination of this preliminary hypothesis could provide clues to the riddle posed by Dietrich and Al-Shawaf (2018): What evolutionary theory explains the ubiquitous phenomenon of ASCs associated with transient hypofrontality?

A Psychophysical State of Women During Natural and Undisturbed Birth as an Altered State of Consciousness

ASCs are difficult to define, partly because of the widespread disagreement over how to define “normal” consciousness (see Dietrich & Al-Shawaf, 2018). For this article, I define ASCs according to the following two criteria: (a) a temporary state from which individuals will eventually return to a “normal” mind state (see Dietrich, 2018) and (b) a state in which it is extremely difficult to simply act (feel, think, behave) as one’s “regular” self. I believe this modest definition enables me to refer to ASCs in general and define a particular experience of natural birth as an altered state with boundaries that distinguish it from other experiences. The literature regarding the conscious state of women during natural and undisturbed childbirth is unsatisfying, to say the least (Leap, Sandall, Buckland, & Huber, 2010; Lowe, 2002; McCutcheon & Brown, 2012). Nonetheless, a number of factors studied suggest that the psychophysical state experienced by many women during childbirth is unique and not a normal, daily conscious experience. First, labor pain is acute because of cervical dilation and descent of the fetus (Buckley & Dip, 2003; Crowther, Smythe, & Spence, 2014; Leap et al., 2010; Lowe, 2002), and for most people, acute pain is not part of their daily conscious experience. Moreover, labor pain is distinct in that the majority of women consistently rate labor pain as severe but do not always report the pain as a negative event (Lowe, 2002; Rowlands & Permezel, 1998). Lowe (2002), for example, conducted in-depth postpartum interviews with Swedish women who delivered in an alternative birth center (where no pain relief, such as an epidural, was available) and identified an interesting theme regarding childbirth pain. The birth mothers had difficulty describing their labor pain, and its experience was contradictory: “It was hell, and a little more, but felt good anyway” (Lowe, 2002, p. 22) and, in a more recent study: “I remember thinking: ‘this hurts but it also feels awesome’” (Van der Gucht & Lewis, 2015, p. 356). In fact, sometimes labor pain during natural and undisturbed birth leads to an experience of pleasure (see Buckley, 2010; Buckley & Dip, 2003; Crowther et al., 2014).

Second, the experience of natural birth can have a tremendous mental impact on women, with the type of delivery² having a particular influence on mothers’ perceptions of their childbirth experience (Conde, Figueiredo, Costa, Pacheco, & Pais, 2008). Women after natural and unmedicated birth often referred to their experience as a life-changing event in the sense of accomplishment and mastery (Caton et al., 2002; Whitburn, Jones, Davey, & McDonald, 2019), a feeling of empowerment (Buckley & Dip, 2003; Crowther et al., 2014; Leap & Anderson, 2008; Leap et al., 2010; Lowe, 2002), and enhanced self-esteem (Lowe, 2002; McCutcheon & Brown, 2012; Simkin, 1991). Furthermore, many women spoke of their experience of natural birth as significant and meaningful (Crowther et al., 2014).³

Bearing in mind that women react and respond differently to the experience of childbirth depending on the circumstances and their individual physiology and expectations, I suggest that there might be a psychophysical state unique to women in labor, even if only in the trivial meaning of conscious experience: Being a woman in natural and undisturbed childbirth is an experience like no other; it is temporary, and it is not a normal, daily, conscious experience. Furthermore, it is obvious that while enduring the acute pain of labor, it is challenging to simply act as usual. Nevertheless, the experience itself, although extremely painful, can also be overwhelmingly positive. Hence, the assumption that a woman can enter a unique psychophysical state during a natural and undisturbed birth and that this state is an ASC.⁴ Because this particular psychophysical state has not yet been given a proper name in the literature, I refer to it as birthing consciousness (see also Dahan, 2019b).

Birthing Consciousness as a Case of Transient Hypofrontality

What is it like for a woman during undisturbed natural birth to be in birthing consciousness? According to THT, altered states that are associated with the progressive down-regulation of brain networks supporting the highest cognitive capacities are basically down-regulation of the prefrontal cortex. Most of the cognitive characteristics that such down-regulation can produce are also experienced by women during natural and undisturbed birth. In the third trimester, general cognitive functioning, memory, and executive functioning are significantly poorer than before pregnancy (see Davies, Lum, Skouteris, Byrne, & Hayden, 2018; Hoekzema et al., 2017). Moreover, recent studies suggest that pregnancy might lead to long-lasting changes in human brain structure (see Hoekzema et al., 2017). Thus, I find it reasonable to assume that during natural birth, these functions remain at a significantly poorer level or reach an even lower level. This phenomenon might be correlated with phenomenological and cognitive characteristics that down-regulation of the prefrontal cortex produces, such as reduced decision-making activity and logic capability and memory loss (Dietrich & Al-Shawaf, 2018).

Significant here, additional examples of phenomenological characteristics produced by down-regulation of the prefrontal cortex are time distortion (VandeVusse, Irland, Berner, Fuller, & Adams, 2007), disinhibition from social constraints (Newton, 1992; Odent, 2003), changes in focused attention (McCutcheon & Brown, 2012; Stenglin & Foureur, 2013), pain reduction (Ketterhagen, VandeVusse, & Berner, 2002; Lowe, 2002; McCutcheon & Brown, 2012; Stenglin & Foureur, 2013; VandeVusse et al., 2007), and increased feelings of floating, calm and peacefulness (Ketterhagen et al., 2002; McCutcheon & Brown, 2012; Stenglin & Foureur, 2013).

Although there is little controversy that natural birth is a painful experience (Lowe, 2002), some women cope well with labor pain, whereas others suffer greatly (Whitburn et al., 2019). Moreover, morphology does not necessarily dictate whether a woman will give birth easily and quickly or will need medical intervention after days of hard labor (Odent, 2019). Whitburn et al. (2019) reviewed the literature on the nature of labor pain, aiming to explain these incongruities on the basis of modern pain science. They concluded that the experience of labor pain is highly individual; it is challenging, emotional, and meaningful. They also identified that cognitive, social, and environmental factors influence labor pain. Odent (2019) suggested that the enormous discrepancies between birthing experiences of modern women indicate that birth physiology is, first and foremost, a chapter of brain physiology.

I believe that the phenomenological, biochemical, and cognitive aspects of natural and undisturbed birth are interconnected, consistent with the transient-hypofrontality brain mechanism. In what follows, I divide my analysis into the phenomenological, biochemical, and cognitive aspects of this ASC, demonstrating that all are naturally interrelated,⁵ attest to the occurrence of transient hypofrontality, and positively affect birth outcomes.

Phenomenological aspects of birthing consciousness

“Uniqueness of the birth experience” was one of the essential themes identified in a recent metasynthesis study of women who underwent natural, unmedicated childbirth (Olza et al., 2018). Immediately after giving birth, women described feelings of pride, joy, unparalleled achievement, and awe:

I honestly never had this kind of joy since I was born. I don’t know where this joy came from. I don’t know how to describe the endless joy that came in me.

That feeling is unique, and in the last birth I was without all medication and therefore I could enjoy this feeling much better. Well, I enjoyed it completely.

It is an intense experience, a powerful life experience. It is naturally magnificent that you, just to find that you are capable of giving birth, to a child, that you can do it. To be such a perfect being that you can do it . . . the feeling you get when you get your newborn child into your arms naturally is indescribable. It is a feeling you cannot compare with anything else. It is awe-inspiring. (Olza et al., 2018, p. 7)

In a recent qualitative study of women who birthed healthy babies at term, following an uncomplicated vaginal delivery at home or in the hospital, the women reported feeling fear, anxiety, calm, anticipation, great joy, and exhaustion (Hall, Foster, Yount, & Jennings, 2018). They also experienced emotional strength and vulnerability. The overarching phenomenon of childbirth reported was a dynamic fluctuation between functioning and falling apart. The women fluctuated between feeling connected to others and feeling alienated because of an insensitive remark or behavior, and between feeling love and joy when the baby was born and feeling too exhausted to muster any emotion at all. The dynamic quality of the experience was intensity. Keeping it together was a pinnacle of joy and triumph; falling apart was a bottomless pit of gloom. At times, positive and negative emotions flowed one after the other, as expressed by one participant: “a lot of emotions you go through . . . hope and power and then self-doubt and fear” (Hall et al., 2018, p. 132).

It appears that in physiological childbirth, pain and comfort are not opposites, but rather are part of the emotion-sensation-environment landscape of birth. The pain experience is complex: Comfort exists contemporaneously with great pain, and pain relief is not synonymous with comfort (Hall et al., 2018). It seems that in the context of childbirth pain, there is a striking qualitative difference between pain in the context of helplessness and suffering and pain in the context of coping resources, comfort, and a sense of accomplishment (Caton et al., 2002).

Van der Gucht and Lewis (2015) analyzed qualitative literature exploring women’s experiences of coping with childbirth pain and identified acceptance as one of the most significant influences on a woman’s ability to cope with pain during childbirth. Many of the women expressed a perception of childbirth pain as challenging and described the inherent paradox of the need for pain to birth their child.⁶ Acceptance allowed them to embrace the pain, enhancing their coping ability. This positive outlook and acceptance of pain was consistent across the socioeconomic, cultural, and contextual differences observed among the women. The findings suggest that the ability to cope with pain during childbirth and the birthing experiences reported are universal (Van der Gucht & Lewis, 2015).

Hence, a woman’s psychological state during labor can modify her pain experience (Aune et al., 2015; Buckley & Dip, 2003; Crowther et al., 2014; Leap et al., 2010; Stenglin & Foureur, 2013; Whitburn et al., 2019). In several phenomenological studies of women’s experience during natural birth, when describing the phenomenological characteristics resembling those of transient-hypofrontality states (noted in the previous section), participants used the expression “in the zone,” meaning inward focusing, being fully focused on doing the job, shutting out the rest of the world, letting go of fear, and being in a nonanxious state (Dixon, 2011; Stenglin & Foureur, 2013). Women who focused their attention on their delivery, rather than on their pain, experienced similar sensory pain but less affective pain (Rowlands & Permezel, 1998; Stenglin & Foureur, 2013).

But what is “focusing” in this context, and how do birthing women accomplish this task, given that labor pain shares many features with other forms of acute traumatic pain (Lowe, Walker, & MacCallum, 1991)? In a recent metasynthesis study, Olza et al. (2018) used techniques of metaethnography to synthesize qualitative studies on women’s subjective experience of natural, unmedicated birth. According to Olza et al. (2018), when contractions became stronger and the pain intensified, women enhanced their ability to cope with labor pain by “withdrawing within as labor intensifies.” This was an essential theme identified by the researchers: a retreat into an inner world where time seemed to be suspended. Women described how this internal space allowed them to concentrate on the birthing process, and this facilitated the feeling that they could manage. For this “withdrawing within” to occur, women needed to feel safe, to be with safe companions and in a protected place.

Women described this withdrawal using words such as “narrowed,” “zone,” “faraway place,” “another planet,” and “private.” They also emphasized focusing on the importance of being in the moment: “Nothing else matters and the universe kind of shrinks to this particular, you know this particular job that you have to do which is you know about birthing your baby” (Olza et al., 2018, p. 6). Women also described perceptions of an altered or suspended sense of time:

My sense of time was completely lost, as if I had forgotten it in a drawer at home. It was a very strange feeling. There are a lot of people around you and yet you are in your own world. Even if we were in the same room we were not in the same world. (Olza et al., 2018, p. 6)

Likewise, hypnobirthing, a method that encourages the laboring woman to focus her attention, was found to be correlated with better birth outcomes (Gavin-Jones & Handford, 2016). Generally, hypnotherapy uses hypnosis to achieve specific therapeutic goals, such as the alleviation of pain or anxiety. Hypnosis appears to encompass different altered states of consciousness, such as daydreaming, meditation, or intense concentration (Cyna, McAuliffe, & Andrew, 2004; Gavin-Jones & Handford, 2016). The use of hypnotherapy during childbirth has long been practiced and is said to be one of the most valuable and rewarding applications of hypnosis. In a systematic review of the effectiveness of hypnosis in relieving labor pain (Cyna et al., 2004), it was found that despite differences between trials in the timing and number of hypnosis interventions reported, outcomes were consistently in favor of hypnosis over conventional analgesia.⁷

To conclude, the psychophysical state of natural and undisturbed birth, although extremely painful, can also be positive. This occurs, in part, when the birthing woman reaches a psychological state of accepting pain and retreating inward. This focusing, or phenomenon of retreating, is correlated with phenomenological characteristics produced by down-regulation of the prefrontal cortex and is notably similar to phenomenological features of transient-hypofrontality states, such as hypnosis, daydreaming, and meditation. Most importantly, this experience during natural and undisturbed birth appears to be universal and cross-cultural.

Linking the phenomenological aspects of birthing consciousness to some biochemical aspects of giving birth

Numerous studies of maternal brain neuroplasticity indicate neurofunctional and neuroanatomical changes in the brain during pregnancy (Almanza-Sepúlveda, Hernández-González, Hevia-Orozco, Amezcua-Gutiérrez, & Guevara, 2018; Farrar, Tuffnell, Neill, Scally, & Marshall, 2014; Hoekzema et al., 2017; Kim, Strathearn, & Swain, 2016; Lübke, Busch, Hoenen, Schaal, & Pause, 2017; Macbeth & Luine, 2010; Roos, Robertson, Lochner, Vythilingum, & Stein, 2011). There has been surprisingly little brain research involving the specific episode of childbirth. Researchers do understand, however, more about the biochemical aspects of giving birth—the hormones involved in labor, such as corticotropin-releasing hormone, oxytocin, endorphin, epinephrine, norepinephrine, prolactin, estrogen, progesterone, vasopressin, and brain-derived neurotrophic factor (Sayiner, Murat Öztürk, Ulupinar, Velipasaoglu, & Polat Corumlu, 2019).

As noted in the previous section, it appears that women can modify their pain experience during natural and undisturbed birth by focusing and retreating. Here may lie the connection between the phenomenological and the biochemical aspects of birth: There are some hormonal features unique to labor pain that arise from pregnancy-induced changes at different stages of nociception (Lothian, 2004; Odent, 2008), and some of these biochemical changes appear to act synergistically to promote antinociception that peaks at the time of birth (Rowlands & Permezel, 1998). Lothian (2004) referred to the release of these hormones as the “hormone orchestration” of normal labor. The increase in production of oxytocin and the simultaneous production of endorphins and prolactin is the physiology of normal birth. Oxytocin is stored in the anterior pituitary and is released in pulses every 3 to 5 min in early labor. The uterine muscles respond to this rhythm and establish regular surges. The body then releases another hormone, β-endorphin, a natural opiate activating the mesocorticolimbic dopamine reward system, that increases tolerance to pain and even produces feelings of pleasure and euphoria. However, if the birth is disturbed, for example, by the use of epidural analgesia or additional synthetic oxytocin (Pitocin), this process does not occur (Gavin-Jones & Handford, 2016, pp. 30–39; Lothian, 2004).

High euphoria levels are also experienced after the birth is over. The endogenous opiates released during unmedicated deliveries produce feelings of elation, which leads to the postpartum phenomenon experienced by women after natural and undisturbed childbirth referred to in the literature as “the superwoman syndrome.” This phenomenon is the feeling of “being able to do anything” (Cheyney, 2011; Kurz, Davis, & Browne, 2019).

Farley, Piszczek, and Ba˛bel (2019) hypothesized a similarity between running a marathon and giving birth in the context of memory of the pain experience. This analogy is relevant because euphoria levels are significantly increased after running (Boecker et al., 2008), and runner’s high is one of the paradigmatic cases of ASC that is due principally to a transient state of hypofrontality (Dietrich & Al-Shawaf, 2018). According to Farley et al. (2019), labor pain and marathon pain share not only positive emotional valence but also physiological mechanisms. Both physiological childbirth and extreme physical exertion involve a number of endogenous systems and substances that are specific to these two types of experiences, including endocannabinoids and endogenous opioids, and the oxytocin system, which is related to analgesia and memory. It has been demonstrated that oxytocin can impair fear acquisition and influence the memory of both positive and negative emotionally salient stimuli. Farley et al. (2019) hypothesized that, primarily during the encoding phase, oxytocin influences memory of pain through its inhibiting action in the central nucleus of the amygdala during the painful event, (i.e., during memory formation). Note, however, that Farley et al. (2019) did not connect the oxytocin system mechanism to hypofrontality. Further research in this direction may shed light on the biochemical aspects of transient hypofrontality.

Cognitive aspects of birthing consciousness

Pregnancy is a dynamic process during which significant cognitive changes take place, including changes affecting memory (Almanza-Sepúlveda et al., 2018; Glynn, 2010; Raz, 2014). Almanza-Sepúlveda et al. (2018) examined cortical electroencephalographic correlations during performance of working memory tasks in each trimester of pregnancy.⁸ Although the neural system responsible for working memory is known to involve a large number of brain regions, evidence from neurophysiological and lesion studies indicates that the prefrontal cortex is key. In particular, the dorsolateral region and its functional connections with the posterior parietal cortex are primary in relation to both verbal and visuospatial working memory processes. Almanza-Sepúlveda et al. (2018) found that although pregnancy had only a subtle effect on the visuospatial working memory task, different patterns of cortical synchronization were found in each trimester of pregnancy. They maintained that these patterns could represent adaptive mechanisms enabling the pregnant women to focus their attention and activate additional cognitive resources necessary to solve the working memory tasks adequately. Thus, it has been suggested that working memory is affected during gestation as a result of functional changes in cortical areas such as the prefrontal and parietal cortices.

Simkin (1991) explored and analyzed the long-term impact of the birth experience on a group of 20 women from the natural-childbirth culture of the late 1960s and early 1970s. Interviewed 15 to 20 years later, women in this study reported that their memories from their births were still vivid and deeply felt. In contrast, when Elkadry, Kenton, White, Creech, and Brubaker (2003) interviewed 277 ethnically diverse women after a median interval from delivery of 10 weeks, only 40% of the women answered all questions correctly. Moreover, 60% of the mothers could not recall accurately a minimum of one major labor-management event; however, those who had given birth by cesarean section had a better recollection of many details.

These findings are significant when combined with those of Farley et al. (2019) regarding pain, memory, and oxytocin. Women who experience natural and undisturbed birth may retreat into a kind of “inner world,” and when combined with the effects of hormones, especially oxytocin, one of the consequences is some memory impairment, which is associated with a hypofrontality state. In addition, Simkin’s (1991) conclusion may be explained in terms of the two themes identified by Olza et al. (2018) regarding the natural birth experience: “uniqueness of the birth experience” and “withdrawing within as labor intensifies.” It is possible that women who experienced natural birth remembered the sensations vividly because of the uniqueness of the experience, but when they were asked could not be specific about a major labor-management event because they retreated to an inner world in order to cope with the extreme pain. In light of the lack of evidence for what may be conflicting findings, further empirical research is required.

Additional cognitive features are related to the transcendent state during certain stages of childbirth, as described in the phenomenological section. Birthing consciousness apparently involves shifting into a nonverbal state during which the birthing woman does not want, or is even unable, to talk (Cyna et al., 2004; Lundgren & Dahlberg, 2002). Related cognitive features are difficulty assessing the passage of time, a strong physically and mentally dissociative state characterized by removal from surroundings to varying degrees, disorientation, and shifted awareness (Olza et al., 2018; Zambaldi, Cantilino, Farias, Moraes, & Botelho Sougey, 2011).

Zambaldi et al. (2011) reported that traumatic childbirth was an important predictive factor for perinatal dissociation. However, 15 of the women who experienced dissociation (40.5%) had dissociative symptoms even though they did not consider their childbirth to be a traumatic event. Given the orientation of traumatic childbirth of this and other current studies dealing with dissociation features during childbirth (e.g., Thiel & Dekel, 2019), I believe it would be interesting to research the following questions: What proportion of women experience dissociative states during a positive natural birth? What individual differences, if any, predict these states? Is there any correlation between such dissociative states and birthing consciousness as described here? Future research might reveal that these cognitive and phenomenological features during birthing might be linked not only to pathology but also to positive birth experience and perhaps even to positive birth outcomes. Current evidence is tenuous, as was noted recently by Kurz et al. (2019) in reference to “transcendent” birth experiences: “While the pathological end of the spectrum of psychosocial wellbeing after birth is well recognized, we often fail to articulate how the other, more positive end of the spectrum might be experienced” (p. 24).

Odent (2019) associated other behaviors with a reduction of neocortical activity. During the advanced stages of physiological, unmedicated, and undisturbed childbirth, many women become less rational, exhibiting socially unacceptable behaviors such as screaming, swearing, and finding themselves in the most unexpected, bizarre, often mammalian, quadrupedal postures (Gavin-Jones & Handford, 2016; Newton, 1992; Odent, 2019). Odent (2019) noted that he used the terms “neocortical activity” and “neocortical inhibition” without referring to the extreme complexity of the human neocortex because precise technical terms are not necessary to understand the essential. Because no direct research has been conducted on the exact neurophysiological states of women during natural and undisturbed birth, my hypothesis that the brain mechanism of birthing consciousness is transient hypofrontality is oversimplistic from a neuroscientific point of view. However, the phenomenological and cognitive aspects of birthing consciousness described so far are consistent with the phenomenological and cognitive aspects of transient hypofrontality. Validating my hypothesis requires neurophysiological research of the physiology of the crucial elements of birthing consciousness described here. Future studies can search for evidence of reduction in neocortical activity during different stages of labor and outline, in detail, precisely where in the neocortex such modification occurs. Measuring this brain mechanism without disturbing the exact psychophysical state being measured will be challenging, because an essential characteristic of the state is being undisturbed and private.

Potential positive outcomes of inducing the state of birthing consciousness

Pain-catastrophizing during labor can influence the need for pain relief, as well as the obstetric outcome (Veringa, Buitendijk, de Miranda, de Wolf, & Spinhoven, 2011; Wuitchik, Bakal, & Lipshitz, 1989). Anxiety about labor is a predictor for negative consequences, including maximum pain during labor, dystocia, and emergency cesarean section (Leap et al., 2010). According to Boucher, Bennett, McFarlin, and Freeze (2009), increased epinephrine levels that occur with anxiety during labor are associated with an increase in the length of labor. Lowe (2002) reported that distress-related thoughts during latent labor predicted longer labors, significantly more instrumental deliveries, and an increase in abnormal patterns of fetal heart rate. Moreover, the negative effects of labor pain are believed to originate primarily in alterations in the maternal respiratory pattern and the catecholamine-mediated stress response. The potential physiological effects of severe labor pain may include increased oxygen consumption and hyperventilation with hypocarbia and respiratory alkalosis, autonomic stimulation and catecholamine release with gastric inhibition and increased gastric acidity, lipolysis, increased peripheral vascular resistance, cardiac output, decreased placental perfusion, and incoordinate uterine activity. At the end of the spectrum, these responses are hypothesized to produce maternal metabolic acidemia, fetal acidosis, and dysfunctional labor (Lowe, 2002).

Today, researchers are seeking how to decrease various interventions during labor, such as cesarean sections, administration of oxytocin, vacuum extraction, and episiotomies, as well as to decrease the rate of anal-sphincter rupture, length of birth, parturition period, and the rate of postpartum hemorrhage (Wrønding et al., 2019). This research trend is due (in part) to the evidence that the negative implications of medicated birth, for the mother and the baby, go far beyond the perinatal period (see Odent, 2001; Peters et al., 2018). Compared with births that involve common interventions, such as synthetic oxytocin or epidural analgesia, physiologic births provide superior outcomes for both mother and baby (Mayberry, Avery, Budin, & Perry, 2017).

The negative implications of medicated birth are not only physiological but also mental. A recent study by Thiel and Dekel (2019) found that women who had assisted vaginal deliveries or unscheduled cesarean sections reported higher peritraumatic dissociation levels than those who had regular vaginal deliveries or scheduled cesarean sections—and peritraumatic dissociation predicted postpartum posttraumatic stress disorder (PP-PTSD) above and beyond premorbid and other childbirth-related factors. Dekel, Stuebe, and Dishy (2017) posited that examining biological factors underlining positive adaptation is likely to provide insight into the underresearched scientific territory of PP-PTSD symptoms. Moreover, the complex role of peritraumatic dissociation as potentially adaptive on the one hand and maladaptive on the other hand, warrants future scientific attention (Thiel & Dekel, 2019).⁹

Many of the solutions offered to decrease various interventions during labor involve improving the birthing mother’s mental well-being. For example, there is a growing body of evidence indicating that doula support improves childbirth outcomes (Brisco & Small, 2017; Kozhimannil et al., 2016; Kozhimannil, Hardeman, Attanasio, Blauer-Peterson, & O’brien, 2013; Manning-Orenstein, 1998) and that practicing yoga during pregnancy has positive therapeutic effects during birth (Chuntharapat, Petpichetchian, & Hatthakit, 2008; Narendran, Nagarathna, Narendran, Gunasheela, & Nagendra, 2005). In addition, it is now accepted that the birthing environment can support or hinder birth physiologically (Sayiner et al., 2019; Stark, Remynse, & Zwelling, 2016); therefore, solutions also include redesigning labor rooms (Foureur et al., 2010; Hodnett, Stremler, Weston, & McKeever, 2009) and dimming the lights in the delivery room (Wrønding et al., 2019). These empirical findings indicate that interventions improving the mental well-being of birthing mothers, together with their physical surroundings, can optimize the chances of women undergoing natural childbirth.

Furthermore, conceptualizing labor pain as purposeful and productive may improve women’s experience of pain and reduce their need for medication (Whitburn et al., 2019). Thus, entering birthing consciousness (as described), the altered state of the mind–body during natural birth that is associated with calmness, focusing, and reduced affective pain, fear, and anxiety can increase the possibility of an easier and healthier delivery for both mother and baby.

Connecting the dots: from birthing consciousness as a case of hypofrontality to its probable outcomes

Pregnancy produces alterations in maternal physiology that are necessary for maintaining gestation, fetal development, and childbirth (Glynn, 2010). Among the mechanisms affected are those regulating emotion and cognition. According to Roos et al. (2011), the prefrontal cortex is key to emotion regulation via its control of a range of limbic and subcortical structures, including the amygdala and hippocampus. Furthermore, because glucocorticoids (e.g., cortisol) and gonadal hormones (e.g., estrogen, progesterone, and testosterone) are thought to be involved in emotion regulation generally, it is possible that these hormones affect the prefrontal cortex in regulating emotion and cognition in pregnancy. Therefore, Roos et al. (2011) hypothesized that pregnancy is characterized by altered prefrontal cortex function.

Many researchers in the field of obstetrics maintain that some reduction in neocortex activity might be a necessary condition for the body to release the hormonal cocktail needed for natural labor, containing oxytocin, endorphins, and prolactin (Cunningham, 2016; Gavin-Jones & Handford, 2016; Lothian, 2004; Odent, 2019). Moreover, Odent (2019) argued that women giving birth must be protected against any sort of neocortical stimulation. The main stimuli of neocortical activity are language, bright lights, the feeling of being observed, and situations associated with a release of catecholamines (Gavin-Jones & Handford, 2016, pp. 30–39; Odent, 2003). The absence of undesirable external stimulation is, in and of itself, insufficient; the path to reducing neocortex activity travels through letting go of control (Gavin-Jones & Handford, 2016) and release of some inhibitions (Gavin-Jones & Handford, 2016; Newton, 1992; Odent, 2003). This release is, in fact, similar to our behavior during sexual activity (Cunningham, 2016; Neerland, 2013; Newton, 1992; Odent, 2007, 2008).¹⁰

The above phenomenological, cognitive, biochemical, and physiological data are essential to interpret the particular state of consciousness that characterizes women during natural labor. According to Cunningham (2016), instinct shows itself only when some areas of the neocortex are at rest. Furthermore, according to Roos et al. (2011), prefrontal cortex function appears to be altered during the processing of fear-relevant stimuli in pregnancy. Changes in hormone levels may lead to changes in prefrontal cortex function and, in turn, to changes in cognitive–affective processing and anxiety. These findings are consistent with the hypothesis that oxytocin can impact pain and fear memory on several levels. For example, oxytocin can reduce the activity in brain regions responsible for fear-memory formation or retrieval, resulting in an acute anxiolytic effect. This phenomenon has been reported to occur after injecting oxytocin into the medial prefrontal cortex and amygdala (see Farley et al., 2019, for details). The model proposed by Maroun and Wagner (2016) is also consistent, explaining some of the contradictory effects of oxytocin as products of the balance between two networks in the amygdala that are controlled by the medial prefrontal cortex.¹¹

During childbirth and any sexual activity, potential inhibitions originating in the neocortex await triggering (Cunningham, 2016; Neerland, 2013; Newton, 1992; Odent, 2007, 2008). Because birthing is instinctive, intimate, and private, releasing socialized inhibitions is likely a necessary condition for a natural birth (Gavin-Jones & Handford, 2016, pp. 30–39; Odent, 2001). Carlström (2018) noted that in Western society, the widely accepted view is that the functional body ought to be clean and hygienic; contact with body fluids is, in many situations, surrounded by taboos. However, body fluids are integral to natural birth, a process steeped in blood, urine, and feces. To say the least, childbirth is a very messy event. It follows that because feeling shame (over the release of body fluids) is a higher cortical function originating in the neocortex (Scherer, 1982), it can hinder the delivery of the baby because of its potential effect on the release of birthing hormones. For example, in a functional MRI study (Michl et al., 2012), specific activations for shame were found in the frontal lobe (medial and inferior frontal gyrus).

Evidence demonstrating that other mammals may enter a related brain state while birthing that is associated with down-regulation of some brain functions further supports the suggested hypothesis. For example, Newton, Peeler, and Newton (1968), in a study of the effect of disturbance to labor on laboratory mice, reported that significantly more mice gave birth in a familiar, covered nest box than those who were moved to a glass nest box. In other words, even the birth outcomes of mice drop when they are disturbed and removed from a familiar and safe place to an unfamiliar and unintimate place, a step that activates the neocortex (see also Newton, Foshee, & Newton, 1966). Likewise, lack of attention to a birthing woman’s inherent need not to be disturbed in the typical hospital environment is correlated to a high rate of cesarean sections, routine use of epidurals in labor, and a high incidence of instrument deliveries (Aune et al., 2015; Buckley, 2015; Buckley & Dip, 2003; Crowther et al., 2014; Hodnett et al., 2009; Jansen, Gibson, Bowles, & Leach, 2013; Lothian, 2004; Sakala, Romano, & Buckley, 2016; Sayiner et al., 2019; Stenglin & Foureur, 2013; Walsh, 2009).

The connection to the THT brain mechanism is as follows: It is reasonable to assert that some women reach an ASC during childbirth, and it is also reasonable to assume that the ASC I have described occurring during physiological birth is most likely a case of hypofrontality. Figure 1 summarizes my hypothesis and its connection to the data introduced in previous sections. Birthing consciousness is associated with focused attention, calmness, less-affective pain, less fear, and less anxiety. I hypothesize that hypofrontality is crucial to physiological birth, because this brain mechanism makes it easier for a woman to focus her attention and retreat to an inner world. Blocking potential inhibitions enables the relevant parts of the brain to release the different hormones needed for reducing pain, fear, and stress, thus enabling the birth process to proceed optimally. This general picture may support my hypothesis that birthing consciousness is related—physiologically, phenomenologically, and cognitively—to transient hypofrontality. I contend that it would be reasonable to assume that the ACS I term birthing consciousness is triggered by the same brain mechanism and carries the same psychological aspects described by THT.

Fig. 1.

From birthing consciousness as a case of hypofrontality to its probable outcomes. TH = transient hypofrontality.

“Birthing Consciousness” Is Probably an Adaptation, for It Was Essential to Reproduction Throughout Most of Human History

Because the phenomenological characteristics of birthing consciousness are correlated with better health outcomes for the mother and for her baby, and because fear, stress, and pain during labor are predictors of negative consequences, including maximum labor pain, dystocia, and emergency cesarean section, I contend that before the era of medicalized births, women who could not reach birthing consciousness (or something close) decreased their probability of surviving childbirth in the absence of modern medical assistance during labor. Thus, birthing consciousness (or something close) was essential to reproduction throughout most of human history. Therefore, I suggest the following hypothesis: The psychophysical ability to reach birthing consciousness might be an example of an evolutionary function of consciousness-altering behavior that is associated with transient hypofrontality.

Today, the ability to perform a cesarean section ensures, in most cases, healthy childbirth for mothers and their progeny (Odent, 2007). Throughout most of human history, however, natural birth was the only option for reproduction, and a woman unable to have a vaginal birth did not survive, and neither did her descendant. In addition, women had to be sufficiently healthy after birthing to care for the baby. These hurdles, to the best of my knowledge, have not received sufficient (if any) attention in the literature of evolutionary psychology. I have demonstrated that a woman’s ability to survive childbirth is psychophysical in nature and is most likely due to our “hardwiring.”

I contend that through principles of natural selection, a female who overcame the acute pain of childbirth by her response, behavior, and her ability to reach birthing consciousness would likely pass that response, behavior, and proclivity on to subsequent generations. In other words, successful responses during contractions, of which the most important is reducing neocortical activity (birthing consciousness or something close), have been passed on to subsequent generations through natural selection: Women without this successful response were disproportionately unlikely to survive natural childbirth and deliver a healthy baby. Furthermore, because birthing consciousness shares many features, both phenomenologically and biochemically, with transient hypofrontality, I contend that the psychophysical ability to reach birthing consciousness could be an example of an adaptive ASC that involves transient hypofrontality.

In summary, I argue the following:

Birthing consciousness is a unique psychophysical state that sometimes occurs during natural and undisturbed labor, which correlates with a shorter and easier birth with better health outcomes for the mother and her baby.

The ability to reach birthing consciousness once had a crucial evolutionary benefit for the survival of the woman and her progeny during childbirth, because throughout most of human history, there was no advanced obstetric medicine available for intervention during birth if necessary.

Women with the proclivity to reach birthing consciousness, which is psychophysical in nature, were more likely to survive and reproduce successfully.

Through principles of natural selection, these women passed this proclivity on to their descendants.

Birthing consciousness shares many of the features of transient hypofrontality (phenomenological and cognitive features) and can be counted as a case of transient hypofrontality.

My hypothesis is as follows: Birthing consciousness is an example of an adaptive ASC that involves transient hypofrontality because this brain mechanism once conferred a crucial evolutionary benefit for women in childbirth.

Discussing a Possibility: Pain-Induced ASCs as Adaptive

Dietrich and Al-Shawaf (2018) asked this key question: Do we possess an evolved psychological mechanism that motivates us to engage in consciousness-altering behavior, or is this universal human behavior simply the side effect of some other evolved capacity? From my hypothesis, it follows that if birthing consciousness is an example of an evolutionary function of consciousness-altering behavior in the special episode of childbirth, then this specific ASC is clearly a psychological adaptation for women.

Herein, I believe, lies an interesting avenue for further research on THT. In the context of transient hypofrontality and pain-induced ASCs, I believe that pain can be divided roughly into two kinds: consensual pain and necessary pain. Examples of consensual pain that can cause transient hypofrontality are the ASC of a submissive during an interaction involving bondage and discipline, dominance and submission, and/or sadism and masochism (BDSM; Ambler et al., 2017; Dahan, 2019b; Pitagora, 2017; Sagarin, Lee, & Klement, 2015); ASCs that are caused during various extreme rituals (Lee et al., 2016); and, of course, various activities of extreme sports, including runner’s high (Dietrich & Al-Shawaf, 2018). Necessary pain is pain that is not chosen, such as the case described here of the acute pain experienced during the birthing process. Recently, chronic lower back pain has been described by some cognitive aspects of transient hypofrontality (Hamacher, Hamacher, Herold, & Schega, 2016; Hamacher, Hamacher, & Schega, 2014).

Of course, there are typical ASCs with transient-hypofrontality brain mechanisms that are not pain-induced at all, such as dreaming, daydreaming, hypnosis, and meditation. However, one can see that even in these ASCs, which are not pain-induced, some of the noted effects of transient hypofrontality are pain relief (for example, in the case of meditation, see Zeidan, Grant, Brown, McHaffie, & Coghill, 2012) and/or other therapeutic benefit (such as in the case of hypnosis, see Brugnoli, 2016; or daydreaming, see Gold & Cundiff, 1980). Thus, it seems that every ASC involving the TH brain mechanism is also linked to reduced pain perception, whether physical or mental, and thus may represent a therapeutic benefit. Because ASC behaviors are older than our species or even the entire hominin line (other animals also enter into ASCs), I propose here a tentative explanation for the appeal of altered states of consciousness: Perhaps we are hard wired to desire reaching states linked with transient hypofrontality because this brain mechanism once conferred a crucial evolutionary benefit in situations of acute pain. If so, it is possible that natural birth and other pain-induced ASCs benefit from a much more ancient and broader adaptation. It is possible, in my opinion, that this evolutionary explanation for the ubiquitous phenomenon of ASCs associated with transient hypofrontality can be roughly divided in two: Pain-induced ASCs are adaptive, whereas ASCs that are not pain-induced benefit from this brain mechanism because of its therapeutic effects. Clearly, this idea is very tentative and needs further development, which is beyond the scope of this article.

Conclusion

In this article I introduced three significant points and a path to further research related to THT. First, I argued that birthing consciousness is a psychophysical altered state that women can experience during natural and undisturbed birth. Second, I characterized birthing consciousness from several interrelated perspectives—phenomenological, cognitive, and biochemical—while showing that this ASC possibly shares a similar brain mechanism to that postulated by the THT. Third, I argued that birthing consciousness is probably adaptive, because until recently—in evolutionary terms—women lacking the proclivity for this specific brain mechanism had a lower chance of reproducing successfully. Finally, I briefly discussed the idea that birthing consciousness is but one example of a pain-induced ASC associated with transient hypofrontality that is adaptive. Future research into this idea may bring us closer to resolving the riddle posed by Dietrich and Al-Shawaf (2018): What evolutionary hypothesis can explain the ubiquitous phenomenon of ASCs associated with transient hypofrontality?

The data on the cognitive and physiological states of women during natural and undisturbed birth are rather scarce compared with the data on different stages of pregnancy and the postpartum period. Moreover, no direct research has been conducted to date on the exact neurophysiological states of women during natural and undisturbed birth. Hence, my hypothesis that the brain mechanism of birthing consciousness is transient hypofrontality is tentative and, at this point, necessarily oversimplistic. Validating the hypothesis requires neurophysiological research of the physiology of crucial elements of birthing consciousness as described here.

In this article, I hypothesized that birthing consciousness can be readily distinguishable from other psychophysical states. However, as I noted, future research is needed to characterize this state physiologically. If research proves that “birthing consciousness” is not a well-defined state with clear physical boundaries, then perhaps there is no distinct psychophysical state associated with childbirth, and a mix of preexisting physical and mental states that likely arise throughout the birthing process would be more suitable to describe the natural-birth psychophysical event.

If, however, birthing consciousness can be documented as a relatively discrete state of consciousness, as I presume, then ensuing neurophysiological studies can deepen understanding of the birthing process, and the current article, although theoretical and hypothetical, will have provided knowledge of the conscious state of women during natural and undisturbed childbirth. The hypothesis offered here is novel in linking birthing consciousness to hypofrontality and, hopefully, can benefit current obstetrical care where operative interventions are on the rise, suggesting that reaching birthing consciousness is possible for a significant number of women.

Footnotes

Acknowledgements

I sincerely thank Michel Odent for an e-mail conversation concerning recent neuroscientific evidence of brain preparation for the birthing process.

Transparency

Action Editor: Laura A. King

Editor: Laura A. King

ORCID iD

Orli Dahan

Notes

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