Sensors, sampling rates, filter and notch settings, and peak-to-peak ranges will be standardized with respect to the limitations of various recording instruments. In brief, EEG and EOG signals are sampled at a minimum of 200 Hz, ECG and EMG (chin and leg movement) channels at 200 Hz, and respiratory signals at 32 Hz, except for nasal pressure which is collected at 128 Hz. Respiratory belts, airflow and CO2 cannulas are placed using standardized placements. Oximeter sensors are attached to a finger of the non-dominant hand or to a toe. Scalp electrodes are attached according to the International 10-20 system as well as behind the ears at the left (M1) and right (M2) mastoid areas and 3 over the submental muscles. EOG electrodes are applied 1 cm below and 1 cm lateral to the outer canthus of the left and right eye and will be referenced to an electrode at FPz. When possible, electrodes are secured using water soluble pastes, increasing the holding power by using an adhesive enhancer and cleaning agent. Isopropyl alcohol will not be used for any phase of participant preparation or electrode placement. Sensors are placed, calibrated, and signal quality/impedance checked, recording these data on study forms (Appendix A). Sensor positions are modified as needed to improve signal quality, replacing electrodes if impedances > 5 kohms.
All gold disk scalp electrodes will be placed according to the International 10-20 System
Electrodes For CHAT PSG | Placement Standard for CHAT PSG | Sensor Used for Signal |
---|---|---|
Reference | Mid-forehead (FPz) | Gold cup |
Ground | Slightly posterior to Cz | Gold cup |
E1 | 1 cm lateral + 1 cm below outer canthus L eye | Gold cup or Ag/AgCL patch |
E2 | 1 cm lateral + 1 cm below outer canthus R eye | Gold cup or Ag/AgCL patch |
F3 | Left frontal | Gold cup |
F4 | Right frontal | Gold cup |
C3 | Left central | Gold cup |
C4 | Right central | Gold cup |
T3 | Left temporal | Gold cup |
T4 | Right temporal | Gold cup |
O1 | Left occipital | Gold cup |
O2 | Right occipital | Gold cup |
M1 | Left mastoid process | Gold cup |
M2 | Right mastoid process | Gold cup |
LChin | Below chin, left of geniohyoid muscle | Gold cup or Ag/AgCL patch |
RChin | Below chin, right of geniohyoid muscle | Gold cup or Ag/AgCL patch |
CChin | Ledge of chin, on mentalis muscle | Gold cup or Ag/AgCL patch |
ECG1 | Below right clavicle | Gold cup or Ag/AgCL patch |
ECG2 | Below left clavicle | Gold cup or Ag/AgCL patch |
ECG3 | Left lower rib | Gold cup or Ag/AgCL patch |
RLeg1 | Right leg, belly of Tibilias Anterior muscle, 3 cm. apart | Gold cup or Ag/AgCL patch |
RLeg2 | Right leg, belly of Tibilias Anterior muscle, 3 cm. apart | Gold cup or Ag/AgCL patch |
LLeg1 | Left leg, belly of Tibilias Anterior muscle, 3 cm. apart | Gold cup or Ag/AgCL patch |
LLeg2 | Left leg, belly of Tibilias Anterior muscle, 3 cm. apart | Gold cup or Ag/AgCL patch |
Airflow (nasal/ oral) | Below nose, above upper lip | Dymedix airflow with RERA-quality cable |
Nasal Pressure | Nasal Cannula at floor of nares | Salter or Protech Cannula (Dual-end for NP & CO2) |
Chest | Upper chest, below armpit | Pro-Tech, Z-Rip system |
Abdomen | Lower abdomen, on or slightly above umbilicus | Pro-Tech, Z-Rip system |
Sum | Pro-Tech, Z-Rip system | |
Oximetry (SpO2) Pleth wave form or other quality indicator | Non-index fingertip on non-dominant hand, Nonin XPod Model 3012 or comparable on-board with quality indicator (i.e.:Masimo) | Reusable or disposable Nonin Finger oximeter sensor, Nonin 8000J or 8008J or other to interface correctly with on-board (dependent on finger size) |
Snore Mic | This signal is not obligate for CHAT | Standard sensor, if used in clinical lab |
Position | Middle of upper chest, may be on chest belt | The correct sensor for your PSG instrument |
Capnography, EtCO2 | Nasal Cannula at floor of nares | Numeric Display Salter or Protech Cannula (Dual-end for NP & CO2) |