The following material is based on Panksepp (1998). See also College of Integrated Science and Technology, James Madison University.
Emotion System: FEAR system.
Animal Emotions corresponding to this system: Fear, anxiety, alarm and foreboding
Corresponding Environmental Challenge (generic intentional object): Pain and the threat of destruction
Motivation: Avoiding the threat of bodily harm
Characteristic behaviour: Freezing (mild intensity); flight (high intensity); scanning and vigilance
Associated bodily states: Increases in heart rate, blood pressure, the startle response, elimination and perspiration; respiratory changes
Key sites in the brain: Hierarchical. Amygdala regulates anterior & medial hypothalamus, which regulates periventricular gray substance in lower brain stem, which regulates autonomic indices of fear through spinal cord. Lower components can operate without higher ones.
Key brain chemicals: NMDA glutamate plus various neuropeptides (CRF, alpha-MSH, ACTH, CCK and DBI) |
Emotion System: RAGE system
Animal Emotions corresponding to this system: Rage, anger
Corresponding Environmental Challenge (generic intentional object): Events that restrict the animal's freedom (physical restraint or irritation of the animal's body surface) or access to resources (e.g. an invasion of the animal's territory)
Motivation: The need to compete effectively for environmental resources.
Characteristic behaviour: Tendency to strike out at, attack, bite or fight the offending agent (a living creature).
Associated bodily states: Invigoration of musculature; increase in heart rate, muscular blood flow and temperature
Key sites in the brain: Hierarchical system. Medial amygdaloid area regulates ventrolateral and medial hypothalamus, which regulates periaqueductal gray in the mid-brain. Aggressive signals from top levels depend on functioning of lower levels, but not vice versa.
Key brain chemicals: Substance P, glutamate and acetylcholine |
Emotion System: PANIC system
Animal Emotions corresponding to this system: Loneliness, panic, grief
Corresponding Environmental Challenge (generic intentional object): Social loss
Motivation: The urge to be reunited with companions after separation, which helps to create social bonding
Characteristic behaviour: Cries of distress when separated from caregiver
Associated bodily states: Decreases in body temperature, sleep and growth hormone secretion. Increases in brain arousal, behavioural reactivity, sucking tendencies and corticosterone secretion.
Key sites in the brain: Cingulate cortex, septal area, ventral bed nucleus of the stria terminalis, preoptic area, dorsomedial thalamus and periaqueductal gray
Key brain chemicals: Glutamate and CRF |
Emotion System: Exploratory, appetitive SEEKING system
Animal Emotions corresponding to this system: Anticipatory eagerness
Corresponding Environmental Challenge (generic intentional object): Positive environmental incentives such as food, water, sex and warmth.
Motivation: The need for food, water, sex and warmth.
Characteristic behaviour: Stimulus-bound appetitive behaviour: forward locomotion, sniffing, and investigating, mouthing and manipulating objects in the animal's environment. Also self-stimulation - a tendency to engage in events that increase the animal's arousal.
Associated bodily states: Energisation and a feeling of invigoration. Excitation of the lateral hypothalamus. Sustained nural firing in the brain's dopamine system.
Key sites in the brain: Lateral hypothalamus continuum, which runs from the ventrotegmental area at the back of the hypothalamus to the nucleus accumbens. Also the medial septal area, amygdala and frontal cortex.
Key brain chemicals:Dopamine, norepinephrine and epinephrine, serotonin, (site-specific effect), glutamate and acetylcholine. |
Emotion System: PLAY (special purpose system)
Animal Emotions corresponding to this system: Play
Corresponding Environmental Challenge (generic intentional object): Opportunity for rough-and-tumble play with conspecifics
Motivation: The need for social interaction
Characteristic behaviour: Rough-and-tumble (RAT) play between juveniles or between parent (usually the mother) and offspring. RAT play includes pinning and dorsal contacts, but varies widely among mammals. Solitary running, jumping, prancing and rolling in herbivores may also represent a form of play. Also laughter (humans) or very high-frequency chirping (rats).
Associated bodily states: Changes in skin sensitivity (skin becomes ticklish).
Key sites in the brain: Involves non-specific reticular nuclei - parafascicular complex and posterior thalamic nuclei. More research needs to be done.
Key brain chemicals: Acetylcholine, glutamate and opioids (all non-specific). No specific chemical is known to regulate play. |
Emotion System: LUST (special purpose system)
Animal Emotions corresponding to this system: Sexual desire
Corresponding Environmental Challenge (generic intentional object): Opportunity to procreate
Motivation: The need to procreate
Characteristic behaviour: Males: courting, territorial marking and mounting.
Associated bodily states: Genital arousal, culminating in ejaculation in males.
Key sites in the brain: Medial preoptic area is predominant in males, vwentromedial hypothalamus in females. Also periaqueductal gray in the midbrain. There are inputs from amygdaloid and higher frontal areas too.
Key brain chemicals: Arginine-vasopressin (AVP) - especially in males. Oxytocin - especially in females. Also Luteinizing hormone releasing hormone (LHRH). |
Emotion System: Maternal CARE (special purpose system)
Animal Emotions corresponding to this system: Nurturance
Corresponding Environmental Challenge (generic intentional object): Offspring requiring maternal care
Motivation: The need to care for one's offspring
Characteristic behaviour: Responsiveness to distress signals by offspring. Nursing offspring and providing them with warmth and shelter (e.g. a nest). Gathering offspring together.
Associated bodily states: Lactation. Build-up of mood-altering neuropeptides which promote bonding between mother and infant.
Key sites in the brain: "Brain circuits extend far and wide in the subcortical regions of the brain. Part of the circuitry descends from the preoptic area along a dorsal route through the habenula to the brain stem, and part through a hypothalamic route to ventral tegmental (VTA) dopamine systems and beyond" (Panksepp, 1998, p. 253).
Key brain chemicals: Oxytocin (vasotocin in birds), opioids, prolactin and estrogen. |
Glossary The vertebrate brain can be subdivided as follows: hindbrain (rhombencephalon)lower brainstemmedulla oblongatametencephelonponscerebellum midbrain (mesencephalon)tectumtegmentum forebrain (prosencephalon)diencephalonthalamushypothalamuspineal glandpituitary glandtelencephalonamygdalabasal gangliacaudate nucleusputamenglobus pallidusstriatumhippocampuscerebral cortexfrontal lobetemporal lobeparietal lobeoccipital lobecingulate cortex
Forebrain, midbrain and hindbrain: The three main divisions of the brain. Also known as the prosencephalon, mesencephalon and rhombencephalon. The forebrain includes the cerebral hemispheres of the telencephalon, as well as two main subcortical zones of the upper brain stem, the thalamus and hypothalamus, jointly known as the diencephalon. The midbrain is relatively undifferentiated. The hindbrain divides into the pontine-cerebellar area, or metencephalon, and the medulla oblongata, or myelencephalon. Scientists also divide the brain on a functional basis, into the basal ganglia, the limbic system and neocortex, which are said to specialise in motor performance, emotional behaviour and cognition respectively. The boundaries of these regions are not universally agreed upon; different authors list different structures.
The deepest area in the brain is a group of nerve cells known as the basal ganglia (the so-called reptilian brain). It regulates motor performance and controls essential bodily functions such as elimination, seeking shelter, periods of hunting, basking in the sun, aggressive challenges and submissive displays. It also mediates the emotional behaviour asociated with fear and anger. According to Panksepp, this region includes structures such as the caudate nucleus, globus pallidus, nucleus accumbens, entopeducular nucleus, ventrotegmental area and the substantia nigra.
Surrounding this core is an intermediate layer loosely referred to as the limbic system (also misleadingly known as the old-mammalian brain) which increases the sophistication of the basal ganglia's fear and anger responses and elaborates the social emotions. The limbic system interacts with the visceral organs. According to Panksepp, it includes the amygdala, hippocampus, septal area, preoptic area, hypothalamus, and central gray of the mesencephalon as well as other regions. These zones of the brain mediate emotional processes in all mammals and also regulate the emotional behaviour of the "reptile brain".
Finally, the neocortex (popularly known as the neomammalian brain, although it is found in all vertebrates) surrounds the limbic system and is linked with cognition. The size of the neocortex varies a great deal between species. It is found in all vertebrates but is most pronounced in mammals. The cortex of most mammals has six distinct layers (five in dolphins and whales). The cortex in birds lacks these layers.
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