Some clients cannot tell you what they feel. They can tell you, in precise detail, what their stomach is doing. Consider a composite drawn from a familiar clinical presentation: a client is asked how she feels about her mother’s diagnosis and says she does not really know she is “fine,” she supposes. However, she can describe, unprompted and at length, the cramping that starts an hour after she eats, the bloating that has no dietary explanation, the mornings she cannot leave the house because her bowels will not settle. This pattern is well known in psychosomatic practice. It points to something psychology has long suspected and can now describe with more biological precision: when emotion cannot easily be put into words, the body often continues to register it anyway, and the gut, richly supplied with its own sensory nerve network, is one of the places that registration seems to concentrate.
The Unseen Side of Psychosomatics
Long before neuroscience had a name for the gut-brain axis, clinicians working in psychosomatic medicine had already identified this pattern under a different label: alexithymia, a term introduced by Peter Sifneos (1973) to describe a marked difficulty in identifying and verbally expressing one’s own emotions. Alexithymia is not the absence of feeling; it is the absence of a usable internal vocabulary for feeling. The physiological arousal that accompanies emotion still occurs: heart rate rises, muscles tense, the gut contracts—but without the cognitive labeling that would normally let a person recognize “I am afraid” or “I am grieving.” The working hypothesis in psychosomatic medicine is that when this labeling fails, emotional arousal is more likely to be experienced and interpreted as a bodily complaint rather than a feeling, and functional gastrointestinal disorders have become one of the most studied testing grounds for that hypothesis. This is the part of psychosomatic theory that rarely makes it into wellness coverage of the gut-brain axis, which tends to focus almost entirely on bacteria. The more clinically interesting question is not only what the microbiome is doing to the brain, but what an unprocessed, hard-to-articulate emotional state may be doing to the gut and why some people’s distress consistently shows up as a visceral complaint rather than a verbal one.
The Evidence: Alexithymia and the Gut
The clinical literature here is substantial, though it needs to be read with its methodological limits in view. Porcelli and colleagues, in a series of studies through the 1990s and 2000s, repeatedly found elevated rates of alexithymia among patients with inflammatory bowel disease and irritable bowel syndrome compared with medical and healthy controls (Porcelli et al., 1995; Porcelli et al., 1999). This association has since been consolidated in a systematic review of 48 studies across gastrointestinal and liver conditions, which found alexithymia to be especially prevalent in functional gastrointestinal disorders, present in roughly two-thirds or more of patients in the reviewed studies and consistently linked to poorer subjective symptom experience (Carrozzino & Porcelli, 2018). In a separate prospective study, alexithymia emerged as a stronger independent predictor of poor treatment outcome in irritable bowel syndrome than either gastrointestinal-specific anxiety or depression, meaning that patients who struggled most to identify and articulate their emotional states were also less likely to improve over the course of treatment (Porcelli, De Carne, & Leandro, 2017). It is worth being precise about what this evidence does and does not show. Almost all of these studies are cross-sectional or correlational, drawn largely from patients referred to secondary and tertiary gastroenterology clinics in single-country samples, and relying on one self-report measure of alexithymia, the Toronto Alexithymia Scale—limitations the systematic review itself flags as a constraint on how far the findings can be generalized (Carrozzino & Porcelli, 2018). They establish a robust association between difficulty naming emotions and gut symptom severity; they do not, on their own, prove that unspoken emotion causes those symptoms.
Which Way Does the Arrow Point?
That last caveat matters because the relationship plausibly runs in both directions. Alexithymia is usually treated as a relatively stable personality trait. However, researchers also distinguish a “state” or secondary form that can develop after the onset of a chronic illness, as living with an unpredictable and often stigmatized condition narrows a person’s emotional vocabulary over time rather than the other way around. A twelve-year, population-based study by Koloski et al. (2012) offers a related, broader piece of evidence for this bidirectionality at the level of anxiety and depression rather than alexithymia specifically: elevated anxiety predicted the later onset of functional gastrointestinal disorders, but having an existing gastrointestinal disorder also predicted significantly higher anxiety and depression years later, independent of baseline mood. The most defensible reading of the current evidence, taken together, is not that suppressed feeling straightforwardly causes gut disease, but that a difficulty naming emotion and gut dysfunction can each sustain and intensify the other once either one is present, which is a less tidy story than “unexpressed emotion becomes stomach trouble,” but a more accurate one.
Why the Gut, Specifically?
One candidate mechanism for why this particular organ is so often where the “unnamed” feeling surfaces is interoception: the brain’s largely unconscious monitoring of internal bodily states such as heart rate, breathing, and visceral tension. Craig (2002) mapped the neural pathway through which signals from the body, including the gut, are relayed via the spinal cord and brainstem to the insular cortex—a brain region involved in integrating bodily sensation with subjective feeling. Cameron (2001) applied this specifically to psychosomatic medicine, proposing that many so-called medically unexplained symptoms may reflect a breakdown in how interoceptive signals are consciously interpreted: the body is generating a signal, but the person has limited capacity to read what that signal means emotionally. On this model, a person with alexithymic traits may register a bout of anxiety-driven gut arousal only as a stomach problem because the emotional layer of the signal is harder for them to decode—a plausible mechanism rather than a settled fact, since direct evidence for this specific pathway in humans is still emerging.
A Brief Word on the Biology Underneath
None of this happens in a vacuum. It sits atop a well-documented biological circuit linking the gut and the brain. In short: the gut wall contains its own semi-independent nervous system of an estimated 500 million neurons (Mayer, 2011); this enteric nervous system communicates with the brain primarily via the vagus nerve, and the resident gut microbiota can influence that communication by producing neuroactive compounds and shaping immune signaling (Cryan & Dinan, 2012). Animal studies first demonstrated this concretely: mice given a probiotic strain showed reduced anxiety-like behavior that disappeared once their vagus nerve was severed (Bravo et al., 2011), and human trials have since begun to follow, with one pilot study finding that a gut-targeted probiotic reduced depression scores and altered brain activity on fMRI in patients with irritable bowel syndrome (Pinto-Sanchez et al., 2017). This is the hardware. Alexithymia and interoceptive difficulty describe one hypothesis about what can go wrong in the software running on top of it.
Engel’s Unfinished Argument
This bidirectional, biology-meets-meaning picture is close to what George Engel (1977) was reaching for when he proposed the biopsychosocial model nearly fifty years ago, arguing that biological and psychological processes could not be meaningfully separated in the understanding of illness. Engel’s model was a conceptual challenge to a purely biomedical view of disease; it did not, and could not, specify a physiological pathway. Research on the gut-brain axis and alexithymia does not prove Engel right. However, it gives his argument something it previously lacked: a set of identifiable, testable mechanisms—the vagus nerve, interoceptive signaling, the microbiota-immune axis—through which the “psycho” and the “somatic” halves of his model could plausibly interact.
What This Might Mean in the Room
For clinicians, this reframes a familiar but under-examined presentation while stopping short of a firm clinical rule. A client who struggles to access or articulate their emotional state, but who has a long history of unexplained digestive symptoms, may not be someone who needs to be redirected from body to “the real issue.” Given that alexithymia is associated with poorer treatment outcomes in some gastrointestinal populations (Porcelli et al., 2017), interventions that build interoceptive awareness and emotional labeling—helping a client notice a bodily sensation, sit with it, and slowly attach language to it—are a reasonable, evidence-informed avenue to explore alongside standard treatment, rather than a substitute for it.
Conclusion
The popular version of the gut-brain axis story is about bacteria engineering our moods. The psychosomatic version is quieter, less mechanistically settled, and arguably still clinically useful: it is about what may happen to feeling when a person has limited language for it, and where the evidence suggests that feeling is more likely to surface instead. For some clients, part of the answer may already be sitting in the consulting room, described in careful bodily detail, not yet recognized as an emotional account at all.
Kaynakça
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