Computer-implemented method of detecting parameters indicative of a variation of activation of sympathetic nervous system and of a variation of activation of parasympathetic nervous system in a subject in a transition from a basal condition to a perturbed condition, comprising the following steps: A. receiving a discrete pressure signal p ( t i) of the subject comprising a plurality of heartbeats; B. identifying each heartbeat of the discrete pressure signal p ( t i) and, within each heartbeat, identifying a systolic phase p sys ( t i) and a diastolic phase p dia ( t i); C. building a diagram D sys of duration of the systolic phase as a function of a heartbeat progressive number and a diagram D dia of duration of the diastolic phase as a function of the heartbeat progressive number; D. executing a resampling of the diagram D sys of duration of the systolic phase, obtaining a resampled diagram D sys r of duration of the systolic phase, and a resampling of the diagram D dia of duration of the diastolic phase, obtaining a resampled diagram D dia r of duration of the diastolic phase; E. calculating a power spectrum PSD sys of the resampled diagram D sys r of duration of the systolic phase and a power spectrum PSD dia of the resampled diagram D dia r of duration of the diastolic phase at frequencies between a lower limit frequency f lower-limit and a upper limit frequency f upper_limit higher than the lower limit frequency f lower _ limit; F. calculating a power P LF PSD sys of the power spectrum PSD sys in a LF band, a power P HF PSD sys of the power spectrum PSD sys in a HF band, a power P LF PSD dia in the LF band of the power spectrum PSD dia, and a power P HF PSD dia in the HF band of the power spectrum PSD dia, wherein the frequency f LF in the LF band is higher than or equal to a first intermediate frequency f intermediate _1 and lower than a second intermediate frequency f intermediate _2, thereby f intermediate _ 1 ≤ f LF < f intermediate _ 2, wherein the lower limit frequency f lower _ limit is lower than the first intermediate frequency f intermediate _1, that is in turn lower than the second intermediate frequency f intermediate _2, that is in turn lower than the upper limit frequency f upper _ limit, thereby f lower _ limit < f intermediate _ 1 < f intermediate _ 2 < f upper _ limit, and wherein the frequency f HF in the HF band is higher than or equal to the second intermediate frequency f intermediate _2 and lower than the upper limit frequency f upper _ limit, thereby f intermediate _ 2 ≤ f HF < f upper _ limit; and G. calculating and outputting a value of a ratio LHR sys between the powers in the LF and HF bands of the power spectrum PSD sys and a value of a ratio LHR dia between the powers in the LF and HF bands of the power spectrum PSD dia, thereby LHR sys = P LF PSD sys P HF PSD sys LHR dia = P LF PSD dia P HF PSD dia wherein steps A-G of the computer-implemented method are executed on the subject first in a basal condition and then in a perturbed condition. A. receiving a discrete pressure signal p ( t i) of the subject comprising a plurality of heartbeats; B. identifying each heartbeat of the discrete pressure signal p ( t i) and, within each heartbeat, identifying a systolic phase p sys ( t i) and a diastolic phase p dia ( t i); C. building a diagram D sys of duration of the systolic phase as a function of a heartbeat progressive number and a diagram D dia of duration of the diastolic phase as a function of the heartbeat progressive number; D. executing a resampling of the diagram D sys of duration of the systolic phase, obtaining a resampled diagram D sys r of duration of the systolic phase, and a resampling of the diagram D dia of duration of the diastolic phase, obtaining a resampled diagram D dia r of duration of the diastolic phase; E. calculating a power spectrum PSD sys of the resampled diagram D sys r of duration of the systolic phase and a power spectrum PSD dia of the resampled diagram D dia r of duration of the diastolic phase at frequencies between a lower limit frequency f lower-limit and a upper limit frequency f upper_limit higher than the lower limit frequency f lower _ limit; F. calculating a power P LF PSD sys of the power spectrum PSD sys in a LF band, a power P HF PSD sys of the power spectrum PSD sys in a HF band, a power P LF PSD dia in the LF band of the power spectrum PSD dia, and a power P HF PSD dia in the HF band of the power spectrum PSD dia, wherein the frequency f LF in the LF band is higher than or equal to a first intermediate frequency f intermediate _1 and lower than a second intermediate frequency f intermediate _2, thereby f intermediate _ 1 ≤ f LF < f intermediate _ 2, wherein the lower limit frequency f lower _ limit is lower than the first intermediate frequency f intermediate _1, that is in turn lower than the second intermediate frequency f intermediate _2, that is in turn lower than the upper limit frequency f upper _ limit, thereby f lower _ limit < f intermediate _ 1 < f intermediate _ 2 < f upper _ limit, and wherein the frequency f HF in the HF band is higher than or equal to the second intermediate frequency f intermediate _2 and lower than the upper limit frequency f upper _ limit, thereby f intermediate _ 2 ≤ f HF < f upper _ limit; and G. calculating and outputting a value of a ratio LHR sys between the powers in the LF and HF bands of the power spectrum PSD sys and a value of a ratio LHR dia between the powers in the LF and HF bands of the power spectrum PSD dia, thereby LHR sys = P LF PSD sys P HF PSD sys LHR dia = P LF PSD dia P HF PSD dia