I have found two spinal regions inside Mandelbulb neg power 8 and Cos Pow 8. Enjoy;
NORMAL BULB; a spine (there should be other 6, if you look carefully)
Mandelbulb3Dv17{
Z....Uy...Uv0...N....2.....e0mTdo/.qzea6log0S3ujnu08b00QyynOnW5oB1uszCkcF/nhWCxj
................................McrO6CFJB/2........3./..................y.2...wD
.........c.B..../M.0/......vg...D0....E3.....gVTynlSHAkD/......./K3I0dkpXm1....U
z.....kD12..0.Uj.WPimvstzstiNjm/z6xjJMAlLOP67z1............u1....y1...sD...../..
.z1...sDq3/hmSyX0v1yMucKlHguy40DUCZ27fijAWWmdmm1av1D200BiVxtykyjkb0N0EijPbBB/Dxl
ivH9c.kTChVqy8fGjMinU7iD......IFH.............kD.6....sD..E.0...................
.............oAnAt1...sD....zUmbo9.mTGj.c/8x0UEco9.eVGj.678x0Uico9......M....k1.
.....6OFaz1.......kz.En68.UW..6.P....w/....F....m....s0....F....8/...Qn.....SF52
...U.myxx1kEyd2...........6.oc..xTxi..kuvBTuCfxj3s41pmERLz1..........2.28.kFrA0.
.Ub96aAIVz9.1se7Umvxz0........../EU0.wzzz1...........s/........./.........E.2c..
zzzz.............0...................2./8.kzzzD.................................
/EU0.wzzz1...................................6jtR0krt00EzzVwar7.Tb96.tzDmPSb.wRi
U.IzT7jtR0krt00EQsbwar7.Tb96./bTmPSb.wRiU.2ly7jtR0krt00EMwbwar7.Tb96.lqTmPSb.wRi
U.2kz7jtR0krt00E...cU08.zz/cU08.yz1cU08.xz3cU08.................................
E.U..2....E..........6....EGiFLNbJaQU.pPrJaQ.........................c..........
...................6./........zj................................................
................................................................................
........................}
------------------------------------------------------------------------
COSINE BULB; a spine (there should be other 6, if you look carefully)
Mandelbulb3Dv17{
Z....Uy...Uv0...N....2....k5.umsQSNqzQKNTkWt57zD8470WTjw.zvWDZGIHORszCfaTE08F5yD
................................FEDAUCSUt.2........A./..................y.2...wD
.........ckI..../M.0/.....EQA...j0....E3.....gOn40/mjLlD/......./K3I0dkpXm1....U
z.....kD12../.Uj.WPimvstzstiNjm/z6xjJMAlLOP67z1............u1....y1...sD...../..
.z1...sDSZ.AAt.uJwHXg8mROWVzxW2q/QJTb7hjr/3w8J7biu1cFSO/iIL3z6vy3VKip6jD4zeiDV6.
GvHCXsoyakXwyOtHPDsbhJlD......2V4.............kD.6....sD..E.0...................
.............oAnAt1...sD....zUmbo9.mTGj.c/8x0UEco9.eVGj.678x0Uico9......M....k1.
.....6OFaz1.......kz.En68.UW..6.P....w/...EE....m....U1....F....8/...Qn.....SF52
...U.myxx1kEyd2...........6.oc..xTxi..kuvBTuCfxj3s41pmERLz1..........2.28.kFrA0.
.Ub96aAIVz9.1se7Umvxz0........../EU0.wzzz1...........s/........./.........E.2c..
zzzz.............0...................2./8.kzzzD.................................
/EU0.wzzz1...................................6jtR0krt00EzzVwar7.Tb96.tzDmPSb.wRi
U.IzT7jtR0krt00EQsbwar7.Tb96./bTmPSb.wRiU.2ly7jtR0krt00EMwbwar7.Tb96.lqTmPSb.wRi
U.2kz7jtR0krt00E...cU08.zz/cU08.yz1cU08.xz3cU08.................................
E.U..2....E.....I....2....kEjBLOiJ4IjR5C.IaQ....................................
...................wz.........zj................................................
................................................................................
........................}
Here you see my results using the point and click feature and julia mode;
http://dark-beam.deviantart.com/art/The-holy-spiral-of-Nylander-310383478Cosine spine is more elusive, there are spirals too indeed, here is a "triton" zone
http://dark-beam.deviantart.com/art/Cellini-s-Julia-310552022Tutorial;
http://dark-beam.deviantart.com/art/Mandelbulb-Julia-spine-tuto-310394474