Sensory SystemsSensory SystemsСенсорные системы0235-00923034-5936The Russian Academy of Sciences67577210.31857/S0235009224040068ACYGEUINTEROCEPTIONИНТЕРОРЕЦЕПЦИЯResearch ArticleThe representation of heart contractions in some auditory parts of the temporal cortex in a non-anesthetized catПредставленность сердечных сокращений в слуховых отделах височной коры у ненаркотизированной кошкиBibikovN. G.БибиковН. Г.
Russian Federation
nbibikov1@yandex.ruPigarevI. N.ПигаревИ. Н.
Russian Federation
nbibikov1@yandex.ruJSC N.N. Andreev Acoustic InstituteАО Акустический институт им. акад. Н.Н. АндрееваA.A. Kharkevich Institute of Information Transmission Problems of the Russian Academy of SciencesИнститут проблем передачи информации им. А.А. Харкевича РАНru121220242024384607728022025Received:28022025Published:12122024Copyright ©; 2024, Russian Academy of SciencesCopyright ©; 2024, Российская академия наук2024Russian Academy of SciencesРоссийская академия наукhttps://journals.eco-vector.com/0235-0092/article/view/675772

The inquiry into how cortical neurons respond to interoceptive signals remains a complex puzzle, central to understanding self-awareness in advanced mammals, including humans. A fundamental aspect under scrutiny is whether neural networks in the cerebral cortex of animals can accurately reflect internal bodily states, particularly cardiac activity. To investigate this, we conducted a study on neurons within the temporal cortex of awake and sleeping cat, employing a unique setup enabling continuous differential recording of local potentials in specific cortical regions, alongside monitoring the cardiogram. Our findings revealed intriguing insights. While the primary auditory cortex (AI) exhibited minimal cellular activity synchronized with heartbeats, the secondary auditory zones within the temporal cortex – the anterior ectosylvian sulcus and the posterior ectosylvian gyrus – displayed synchronization with heart rate. This synchronization was particularly evident in local potentials, with certain neurons within these zones responding to sounds and also exhibiting rhythmic activity aligned with heart contractions. Notably, the complexity of phase histograms derived from the cardiogram period suggests that this synchronization is not attributable to artifacts but rather represents genuine neural responses. Our observations prompt consideration of a hypothesis regarding primary self-awareness in both humans and animals. We propose that this phenomenon emerges from the dynamic interaction of two neural ensembles: one representing external sensory input and the other reflecting interoceptive signals, notably from the heart. This interplay between external and internal stimuli may underpin the fundamental experience of the consciousness of self in highly developed organisms.

Исследование того, как корковые нейроны реагируют на интероцептивные сигналы, остается сложной задачей, имеющей решающее значение для понимания самосознания у развитых млекопитающих, включая человека. Фундаментальный аспект, находящийся под пристальным вниманием исследователей, заключается в том, могут ли нейронные сети в коре головного мозга животных точно отражать внутренние состояния организма, особенно сердечную деятельность. Чтобы выяснить это, мы провели исследование нейронов височной коры бодрствующих и спящих кошек, используя уникальную установку, позволяющую непрерывно регистрировать локальные потенциалы и активность одиночных нейронов в определенных областях коры, а также отслеживать различные физиологические параметры животного, включая кардиограмму. Результаты показали, что в первичной слуховой коре (AI) активность, синхронизированная с сердцебиением, либо отсутствовала, либо проявлялась крайне слабо. В то же время вторичные слуховые зоны височной коры, локализованные в передней эктосильвиевой борозде и в задней эктосильвиевой извилине, демонстрировали синхронизацию с частотой сердечных сокращений. Эта синхронизация была особенно очевидна в локальных потенциалах, однако некоторые одиночные нейроны, отвечающие на звуковые сигналы, также проявляли ритмическую активность, синхронную с сокращениями сердца. Форма фазовых гистограмм, построенных на периоде кардиограммы, предполагает, что эта синхронизация обеспечивает получение корой информации о состоянии внутренней среды организма. Эти данные побуждают к рассмотрению гипотезы о возникновении первичного самосознания вследствие динамического взаимодействия нейронных ансамблей, представляющих соответственно внешнюю сенсорную информацию и информацию от внутренних органов, прежде всего от сердца. Такое взаимодействие может лежать в основе чувства собственного “Я” у высокоразвитых организмов.

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