Recently, representants of embodied approach to cognition has suggested that perception is an effect of integration of exteroceptive and interoceptive information. It was demonstrated that tactile, proprioceptive, vestibular, and visceral signals influence perceptual decision-making processes and conscious perceptual experience. Assuming that perception serves survival and taking into consideration a crucial role of visceral signals in keeping homeostasis, interconnections between autonomic and central nervous systems are investigated in search of mechanism regulating their mutual influences. Studies on ANS-CNS interactions during perception reveal that both tonic and phasic ANS activity reflects and influences exteroceptive information processing. Importantly, such effects were mostly demonstrated in experiments monitoring tonic and phasic cardiac activity while performing perceptual tasks. However, not much is known about phasic cardiac activity and a role of ANS-CNS interplay in case of near-threshold perception since most of the studies were conducted on above-threshold stimulation. Thus, in our study, using near-threshold visual discrimination task, we investigated whether barely visible stimuli are able to induce phasic cardiac changes. Moreover, we test how this information might be utilised while making both types of perceptual decisions: stimulus detection/discrimination (type 1 perceptual decision) and metacognitive judgement (type 2 perceptual decision). We found out that phasic cardiac activity differentiates correct from erroneous type 1 perceptual decisions. So, interoceptive signals may serve as an additional source of information while formulating type 2 perceptual decisions and in effect enhance metacognitive accuracy in the near-threshold perception.