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ALCOHOL AND THE NAVAL AVIATOR : WHAT THE 12-HOUR BOTTLE-TO-BRIEF RULE REALLY MEANS. SCOTT SHAPPELL, Ph.D. NAVAL SAFETY CENTER. Shappell 1997. THE VESTIBULAR APPARATUS. HAIR CELLS The Tiny Accelerometer. Acceleration versus Velocity. Otolith Organs (Macula). Acceleration versus Velocity.
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ALCOHOL AND THE NAVAL AVIATOR: WHAT THE 12-HOUR BOTTLE-TO-BRIEF RULE REALLY MEANS SCOTT SHAPPELL, Ph.D. NAVAL SAFETY CENTER Shappell 1997
HAIR CELLS The Tiny Accelerometer
Acceleration versus Velocity Otolith Organs (Macula)
Acceleration versus Velocity Semi-circular Canals
Vision Vestibular Apparatus VESTIBULAR SYSTEM Auditory Proprioceptive BUILDING THE PERFECT ORIENTATION DEVICE Components of the Vestibular System
Vision Cortical Vestibular Apparatus VESTIBULAR SYSTEM Auditory Proprioceptive DON’T FORGET THE “COCONUT” INPUT
Vision Cortical Vestibular Apparatus VESTIBULAR SYSTEM Auditory Proprioceptive Vomiting Center When Components Disagree...
ALCOHOL AND THE VESTIBULAR SYSTEM: AN EXAMPLE OF SENSORY MISMATCH Vision Vision Cortical Cortical Vestibular Apparatus Vestibular Apparatus VESTIBULAR SYSTEM Auditory Auditory Proprioceptive Proprioceptive Puke, spew, up-chuck, blow chunks,ralph, ...
Engage your coconut! Open your eyes, watch TV! Vision Vision Vision Cortical Cortical Cortical Vestibular Apparatus Vestibular Apparatus VESTIBULAR SYSTEM Auditory Auditory Auditory Proprioceptive Proprioceptive Proprioceptive Turn up the volume Put your foot on the floor! Puke, spew, up-chuck, blow chunks,ralph, ... Puke, spew, up-chuck, blow chunks,ralph, ... Puke, spew, up-chuck, blow chunks,ralph, ... SO WHAT CAN WE DO?
Vision Vision Vision Cortical Cortical Cortical Vestibular Apparatus Vestibular Apparatus Vestibular Apparatus VESTIBULAR SYSTEM Auditory Auditory Auditory Proprioceptive Proprioceptive Proprioceptive SO WHAT CAN WE DO?
So how long does it take to clear your endolymphatic fluid of alcohol? 36 hours 24 hours 6 hours 12 hours 48 hours
A Practical Joke to play on your enemies... POST-ALCOHOLIC NYSTAGMUS
Alcohol before flying, a ticking time-bomb... Simply relying on hangover effects like a headache is not sufficient to determine if you should not be flying.
So how do you know when you’re still suffering from the side effects of alcohol? Here’s some home tests that may help! • The Shappell Maneuver • DUI Test
IF YOU DON’T HEED MY ADVICE... Shappell 1997
SENSORY MISMATCH SENSORY MATCH Same Direction as Head Tilt Visual Field Rotation Head Tilt Visual Field Rotation Opposite to Head Tilt Head Tilt SENSORY THEORY OF MOTION SICKNESS
SIMULATOR SICKNESS • Some pilots who rarely become ill in actual flight, report that they become motion sick in the simulator. • Presumably, even though the visual cues accurately represent those which are normally encountered in actual flight, the vestibular cues are absent, hence a visual-vestibular mismatch exists. • As expected, pilots with the most experience in the cockpit have the most difficulty with simulator sickness. For experienced pilots the absence of vestibular cues represents a greater mismatch compared with previous experience than would be the case for novice pilots. • Curiously, experience in either the simulator or actual flight reduces sickness for that particular condition, but increases the probability of discomfort in the other condition. It appears that experience with a particular pattern of interaction provides a baseline of normal "expectations" so that any deviation then becomes a mismatch.
CHEERS Shappell 1997