**4. Conclusion**

This current work has studied the effect of vehicle interior padding thickness on the response of three head form FEM models subjected to an impact loading. The

*Advancement and New Understanding in Brain Injury*

aspect involved in the causes of long-term TBI [22].

significant decrease of the peak strain values. However, when analyzing the middle region of the brain, the peak stresses resulted in a much lower value, overall. The stress wave fluctuations in this region, shown in **Figure 6(a)**, also resulted in a decrease of peak strain values with the presence of the CSF. However, for the most simplified model, SB, the drastic change in strain value due to the stiffness of the system, as well as the stress fluctuations between the coup and contrecoup could potentially cause a significant shear tear-out behavior of the brain tissue. Such behavior could lead to a diffuse injury, or shear injury, which is an important

**Figure 7** illustrates the pressure being transmitted through the brain due to the impact with a padding thickness of 25 mm at various time histories. The pressure

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**Figure 7.**

**Figure 6.**

*Strain-time graph: (a) middle, (b) front.*

*Pressure response: (a) SB, (b) SCB, (c) SCCB.*

numeral results revealed that the responses of the head and the brain under impact load were highly influenced by the padding thickness, the head skull material modeling and assumptions, and neck compliance. The results from this study are summarized as follows:


Overall, the numerical simulations have provided qualitative and quantitative information about the response of the head against impact loading. The current work could be considered an alternative insight to understand the correlation between the vehicle interior padding, various types of head form models, materials modeling, and output parameters such as acceleration, strain, and pressure that can be correlated to TBI resulting from a vehicle crash.
