ageable) uncertainty about bodily and emotional states or the self. 
In other words, in some conditions, the self-injuring pain could be 
more than compensated by the information gain—and the pos-
sibility to generate precise sensations about one’s bodily state. 
By harming the body, we turn it into a very precise source of 
sensations that relieves us from excessive uncertainty about the 
present state and the future course of action. Our (simple) exam-
ple, therefore, illustrates a possible way paradoxical actions could 
be pursued by active inference agents who endure to minimize 
their uncertainty. While self-injuries and other similar behav-
iors are maladaptive in the sense of reducing the fitness of an 
organism, they can still emerge as a result of a correct inference 
that tries to minimize the uncertainty of one’s model of the body 
and the self. This case could particularly fit when some of the 
(precision) parameters of one’s model of the body and the self 
are not appropriately tuned (Fig. 2), producing excessive levels of 
uncertainty.
Having said this, the idea that NSSI behaviors could reflect the 
imperative to minimize uncertainty is not at odds but comple-
mentary to the idea that these behaviors might also be motivated 
by reward achievement (remember that in active inference, both 
uncertainty minimization and utility maximization can be in play 
simultaneously). While NSSI behaviors are associated with a vari-
ety of adverse outcomes, such as negative emotions and distress 
(Klonsky et al. 2003 ), they can also have paradoxically positive 
effects by providing a way to relieve or distract from other sources 
of emotional distress and negative affect (Nock and Prinstein 2004, 
Chapman et al. 2006, Bresin and Gordon 2013, Selby et al. 2019). 
The hedonic effect of NSSI behaviors might be further magnified 
by poor models of one’s body and the self, as suggested by evidence 
that children who engage in NSSI show aberrant responsiveness 
to rewards (Tsypes et al. 2018). Finally, NSSI behaviors have habit-
ual components, which might contribute to their selection, over 
and above consideration of utility maximization or uncertainty 
reduction ( Magerl et al. 2012 ). This body of evidence suggests 
that if uncertainty minimization is a driver of NSSI behaviors, 
as suggested here, it could work in concert with other drivers 
(reward achievement and habit), in ways that are still poorly
understood.
Focusing on uncertainty minimization as a possible factor con-
tributing to NSSI behaviors might also help understand the preva-
lence of NSSI during adolescence. As discussed earlier, people 
in adolescence experience significant changes at many levels—
from bodily states such as body size to interoceptive and hor-
monal processes to affective states and the self. As illustrated 
in Fig. 2, rapid changes (as in the cases of simulated tachycardia 
and bradycardia) determine high levels of surprise and uncer-
tainty that, in some cases, remain elevated, either because some 
of the precision parameters that afford model updates are set 
incorrectly or simply because readapting internal models of the 
body and the self takes time. In periods of rapid changes, such 
as adolescence or after very surprising events, there might be a 
(temporary) misalignment between the predictions of the (out-
dated) internal model and the incoming sensations. For exam-
ple, during adolescence, one might use an outdated model that 
predicts the usual affective states during a party and fail to 
contextualize novel sensations (e.g. unexpected feelings or inte-
roceptive signals when meeting somebody), hence experiencing 
high levels of uncertainty. Thus, failing to reduce this uncertainty 
and achieve a coherent model of oneself could be particularly
distressing.