: Raw, instinctual emotional feelings common to all mammals. Secondary-process : Emotional learning through conditioning.

: The book argues that these emotions are generated in deep, ancient regions of the brain, such as the periaqueductal gray, rather than the higher-thinking cortex.

: Higher-order cognitive ruminations and thoughts about emotions, unique to more complex brains like humans. Reception and Impact Affective Neuroscience Theory and Personality: An Update

Affective Neuroscience: The Foundations of Human and Animal Emotions by Jaak Panksepp is widely regarded as a groundbreaking "Bible" of neurobehavioral science that established a new field dedicated to the neural basis of emotion. First published in 1998, it challenged the long-held scientific dismissal of animal emotions by demonstrating that mammals share evolved, subcortical brain circuits responsible for fundamental feelings.

: Panksepp outlines a structure of emotional processing:

: Panksepp identifies seven "primary-process" emotional systems shared across mammalian species: SEEKING , LUST , CARE , and PLAY (positive) alongside FEAR , RAGE/ANGER , and PANIC/SADNESS (negative).