Quadratic enhancements of the intersection form and spin structures

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If we search spin structures and quadratic enhancements of the intersection form, there are many papers discussing the issue.

  • What are the relations and basic intuitions between the quadratic enhancements of the intersection form and spin structures?

  • What about the $pin^{\pm}$ structures**?

  • are there non-quadratic enhancements? Like cubic or quartic? How?