PLATE 1. SUSAN WRIGHT

A traumatized, desperate person who killed a relative (her husband) but had remorse (Gradation #5). (AP Photo/Pat Sullivan.)

PLATE 2. CLARA HARRIS

A jealousy murderer (Gradation #6). (AP Photo/Pat Sullivan, Pool.)

PLATE 3. CHARLES WHITMAN

A mass murderer sparked by smoldering rage (Gradation #8). (AP Photo.)

PLATE 4. IRA EINHORN

A jealous lover with strong psychopathic traits (Gradation #9). (AP Photo/Bob Edme.)

PLATE 5. JOHN LIST

A killer of people “in the way”; extreme egocentricity (Gradation #10). (AP Photo.)

PLATE 6. NEIL ENTWISTLE

A killer of people “in the way”; full-blown psychopathy (Gradation #11). (AP Photo/Allan Jung, Pool.)

PLATE 7. RICHARD SPECK

An inadequate, rageful psychopath who committed a multiple murder (Gradation #13). (AP Photo/Charles Harrity.)

PLATE 8. JUSTIN BARBER

A ruthlessly self-centered psychopathic schemer (Gradation #14). (AP Photo/Daron Dean, Pool.)

PLATE 9. CHARLES STARKWEATHER

A psychopath on a cold-blooded spree or a multiple murderer (Gradation #15). (AP Photo/Don Ultang.)

PLATE 10. GEORGE HENNARD

A psychopathic person committing multiple vicious acts, including murder (Gradation #16). (AP Photo.)

PLATE 11. TED BUNDY

A sexually perverse serial killer; murder aimed at escaping detection; torture not a primary element (Gradation #17). (AP Photo.)

PLATE 12. DAVID PAUL BROWN AKA BAR JONAH

A torturer-murderer; torture not prolonged (in Brown's case the degree and length of torture could not be decisively evaluated because of lack of evidence) (Gradation #18). (AP Photo/Great Falls Tribune, Wayne Arnst.)

PLATE 13. CAMERON HOOKER

A psychopath committing extreme torture but not known to have killed (Gradation #21). (AP Photo/Paul Sakuma.)

PLATE 14. GERTRUDE BANISZEWSKI

A psychopathic torturer-murderer; torture—the primary motive (Gradation #22). (AP Photo/The Indianapolis Star.)

PLATE 15. LEONARD LAKE

A psychopathic torturer-murderer; torture—the primary motive (in Lake's case, the crime was also sexual in nature) (Gradation #22).

PLATE 16. DAVID PARKER RAY

Psychopathic torturer-murderer; torture—the primary motive (in Ray's case, the crime was also sexual in nature) (Gradation #22). (AP Photo/Judd Bradley.)

PLATE 17. Areas of the brain that deal with our basic drives.

PLATE 18.

How some of the “bottom-up” mechanisms influence some key “top-down” mechanisms.

PLATE 19. Nerve Communication.