Time-related interdependence between low-frequency cortical electrical activity and respiratory activity in lizard,Gallotia galloti

Abstract

Electroencephalograms of medial cortex and electromyograms of intercostal muscles (EMG-icm) were simultaneously recorded in the lizard, Gallotia galloti, during two daily time periods (at daytime, DTP: 1200-1600 h; by night, NTP: 0000-0400 h), to investigate whether a relationship exists between the respiratory and cortical electrical activity of reptiles, and, if so, how this relationship changes during the night rest period. Testing was carried out by studying interdependence between cortical electrical and respiratory activities, by means of linear and nonlinear signal analysis techniques. Both physiological activities were evaluated through simultaneous power signals, derived from the power of the low-frequency band of the electroencephalogram (pEEG-LF), and from the power of the EMG-icm (pEMG-icm), respectively. During both DTP and NTP, there was a significant coherence between both signals in the main frequency band of pEMG-icm. During both DTP and NTP, the nonlinear index N measured significant linear asymmetric interdependence between pEEG-LF and pEMG-icm. The N value obtained between pEEG-LF vs. pEMG-icm was greater than the one between pEMG-icm vs. pEEG-LF. This means that the system that generates the pEEG-LF is more complex than the one that generates the pEMG-icm, and suggests that the temporal variability of power in the low-frequency cortical electrical activity is driven by the power of the respiratory activity.

Temperature-robust rapid eye movement and slow wave sleep in the lizard Laudakia vulgaris

“…5b ). Since respiration has been linked to cortical activity in both mammals 59 and lizards 60 , we used video recordings to track the movements of the ribcage area, which is a proxy for respiration dynamics during sleep (Fig. S3 , Video S2 ).…”

Sleep in invertebrates crayfish

“…Some reptiles seem to have a 'reversed' electroencephalogram, in which the awake period is characterized by waves of slow frequency and large amplitude, sometimes interrupted briefly by periods of desynchronized activity. Furthermore, the amplitude of the signals diminishes with the level of activity of the animal (21,22), and it has been suggested that turtles have a single sleep period that mixes the properties of REM and NREM periods of mammals (23); a similar proposition has been made for sleep in Echidna (14).…”

Effects of Relativistic Motions in the Brain and Their Physiological Relevance

“…This occurs, for example, in regional hysteresis losses when a voluntarily shifted, regional change -which might compose the electroencephalographic pattern -increases or decreases the causal modifications ("inflections") of this field's dynamic, while proceeding conversely (respectively, decreasing or increasing them) for its occasional "neglected" background. What matters is the course of the coupled inflections, not the electroencephalographic synchronization or desynchronization itself: as commented, reptiles and mammals keep paying attention on opposite electroencephalographic regimes; moreover, electroencephalographic activity includes a great deal of potential variations concomitant but unrelated to the mind's actions and reactions; see, e. g., De Vera et al (2005). Thus, whether stirred by the circumstanced psyche (voluntary attentional shift) or by her brain's physiology (involuntary attentional shift), the brain's resulting regular action upon its circumstanced psyche enacts, in her, intonated reactions with variable noergy, that is, more or less interpretable in operational terms.…”