THE PARTICLE ACCELERATION AT INTERPLANETARY SHOCKS HAS BEEN AN ACTIVE FIELD OF OBSERVATIONAL AND THEORETICAL INVESTIGATION IN THE PAST FIVE DECADES; HOWEVER THE SPATIAL DISTRIBUTION OF ENERGETIC PARTICLES ACROSS THE SHOCK CAN NOT BE REPRODUCED BY CURRENT THEORETICAL MODELS IN SEVERAL CASES. WE PROPOSE TO INVESTIGATE THE LOCAL INTENSITY ENHANCEMENTS AT THE SHOCK (SO-CALLED "SPIKES") OF SUPRA-THERMAL PARTICLES HAVING A SPEED WITHIN ONE ORDER OF MAGNITUDE GREATER THAN THE SHOCK SPEED IN THE UPSTREAM FLUID REST FRAME. THIS REGIME HOLDS BEYOND THE VALIDITY OF THE STANDARD DIFFUSIVE SHOCK ACCELERATION MODEL AND HAS BEEN POORLY STUDIED SO FAR. WE CONSIDER THIS WORK AN OVERDUE AND INNOVATIVE APPROACH TO THE SO-CALLED "INJECTION PROBLEM". WE PROPOSE A DATA-GUIDED STUDY TO COMBINE: 1) ANALYSIS AND INTERPRETATION OF INTERPLANETARY SHOCKS HIGH TIME RESOLUTION DATA COLLECTED BY ENERGETIC PARTICLE DETECTORS AND MAGNETOMETERS AT 1 AU ONBOARD ACE (ADVANCED COMPOSITION EXPLORER) AND STEREO (SOLAR TERRESTRIAL RELATIONS OBSERVATORY) A/B; 2) THEORY AND ADVANCED NUMERICAL SIMULATIONS AT SHOCKS PROPAGATING IN A TURBULENT MEDIUM TO INTERPRET THE AVAILABLE DATA. AN ANALYSIS RECENTLY CONDUCTED HAS SUGGESTED THAT THE OBSERVED ANISOTROPY AT SHOCK SPIKES RESULTS FROM BIDIRECTIONAL STREAMING OF IONS ALONG FIELD LINES THAT CROSS THE SHOCK MULTIPLE TIMES AT ODDS WITH A PREVIOUS INTERPRETATION BASED ON PILE-UP OF REFLECTED IONS; WE WILL COMPARE SUCH INTERPRETATIONS IN DETAIL. WE HAVE IDENTIFIED TWO CASES OF SHOCK SPIKE THAT WE WILL ANALYZE IN DETAIL AND WE WILL LOOK FOR OTHER CASES FROM EXISTING AND UPCOMING SPACECRAFT ARCHIVES. WE WILL COMPARE THOSE DATA WITH OUR MULTIPLE-APPROACH SIMULATIONS TO INVESTIGATE THE ORIGIN OF THE SHOCK SPIKES THEIR ANISOTROPY AND TIME-EVOLUTION.