Robert Freitas’ Xenopsychology article has some interesting speculation around this theme. I recommend reading the whole thing, but here are some excerpts to get you interested:
Ganglionic intelligence:
On Earth, evolution favored voted the appearance of intelligence in two major classes of animal nervous systems, called ganglionic and chordate. It has its own peculiar psychology.
The invertebrates, representing perhaps 97% of all animal species alive today, took the ganglionic intelligence option. The earthworm is typical. Each of its many segments is almost an individual organism unto itself, having its own set of kidneys, muscles, sensors and so forth. Coordination is achieved by a thin latticework of nerve fibers crisscrossing from side to side and lengthwise. The ganglionic system resembles a ladder with bulbous neural tissues at the joints. Invertebrate organisms thus are comprised of a collection of sub-brains, each of which controls a separate part of the animal with fairly complete autonomy and no real centralized control. Sensors and their ganglia tend to cluster nearer the head, making not a true brain as we understand the term but rather a large bundle of distinct fibers. Such a nervous system is highly efficient for responding quickly to stimuli. Each clump of nerve cells becomes expert at some particular function–detecting and passing along sensory information, sweeping a leg or swing in wide uniform arc, opening and closing the jaws in slow munching motions during feeding, and so on.
Might extraterrestrials develop a high ganglionic intelligence that has, never developed on Earth despite hundreds of millions of years of opportunity? [...] It is hard for us to imagine the mentality of beings with advanced ganglionic intelligence. Dr. H. Chandler Elliot, a neurologist at the University of Nebraska College of Medicine, notes that humans normally disregard their internal organs. We respond to an empty stomach or a feeling of indigestion but normally we ignore its activities. Says Elliot: “The head of an insect apparently regards not only its viscera but also its legs, wings, and so on, with similar detachment. If one deftly clips off the abdomen of a feeding wasp, the head may go on sucking, obviously not distressed. The mind of such a creature, must be alien to us almost beyond comprehension.” [...]
Yet another possibility is alien minds incorporating the advantages of both ganglionic and chordate architectures. For instance, each invertebrate sub-brain might evolve and enlarge to avoid multiplication of internal interconnections. This development is most likely in a radially symmetrical sea creature, wherein each brain has roughly equal access to sensory input and motor controls. Such creatures would have “collegial” mentalities, something akin to the many voting computers aboard the Space Shuttle, with multiple personalities within each organism and the ability to maintain consciousness under extreme physical trauma so long as any one brain remained functional.
Alien cultural universals:
To illustrate his point, he first refers to an inventory of the elements of human nature compiled by the American anthropologist George P. Murdock during a study of cultural universals:
Age-grading, athletic sports, bodily adornment, calendar, cleanliness training, community organizations, cooking, cooperative labor, cosmology, courtship, dancing, decorative art. divination, division of labor, dream interpretation, education, eschatology, ethics, ethnobotany, etiquette, faith healing. family feasting, firemaking, folklore, food taboos, funeral rites, games, gestures, gift giving, government, greetings, hairstyles, hospitality, housing, hygiene, incest taboos, inheritance rules, joking, kin groups, kinship nomenclature, language, law, luck superstitions, magic,. marriage, mealtimes, medicine, obstetrics, penal sanctions, personal names, population policy, postnatal care, pregnancy usages, property rights, propitiation of supernatural beings, puberty customs, religious rituals, residence rules, sexual restrictions, soul concepts, status differentiation, surgery, toolmaking, trade, visiting, weaving, and weather control.
Wilson insists that few if any of these elements are inevitable outcomes of either high intelligence or advanced social life; rather that “human nature is just one hodgepodge out of many conceivable.” An entomologist by training, he has no trouble imagining an alien insectlike society whose members am even more intelligent and complexly organized than people, yet which lacks many of the qualities listed in Murdock’s inventory. The alien inventory:
Age-grading, antennal rites, body licking, calendar, cannibalism, caste determinism, caste laws, colony-foundation rules, colony organization, cleanliness training, communal nurseries, cooperative labor, cosmology, courtship, division of labor, drone control, education, eschatology, ethics, etiquette, euthanasia, firemaking, food taboos, gift-giving, government, greetings, grooming rituals, hospitality, hosing, hygiene, incest taboos, language, larval care, law, medicine, metamorphosis rites, mutual regurgitation, nursing castes, nuptial flights, nutrient eggs, population policy, queen obeisance, residence rules, sex determination, solder castes, sisterhoods, status differentiation, sterile workers, surgery, symbiont care, toolmaking, trade, visiting, weather control . . . and still other activities so alien as to make mere description by our language difficult.
Alien emotions:
Of course, extraterrestrial sentients may possess physiological states corresponding to limbic-like emotions that have no direct analog in human experience. Alien species, having evolved under a different set of environmental constraints than we, also could have a different but equally adaptive emotional repertoire. For example, assume that human observers land on another and discover an intelligent animal with an acute sense of absolute humidity and absolute air pressure. For this creature, there may exist an emotional state responding to an unfavorable change in the weather. Physiologically, the emotion could be mediated by the ET equivalent of the human limbic system; it might arise following the secretion of certain strength-enhancing and libido-arousing hormones into the alien’s bloodstream in response to the perceived change in weather. Immediately our creature begins to engage in a variety of learned and socially-approved behaviors, including furious burrowing and building, smearing tree sap over its pelt, several different territorial defense ceremonies, and vigorous polygamous copulations with nearby females, apparently (to humans) for no reason at all. Would our astronauts interpret this as madness? Or love? Lust? Fear? Anger? None of these is correct, of course the alien is feeling badweather.
Robert Freitas’ Xenopsychology article has some interesting speculation around this theme. I recommend reading the whole thing, but here are some excerpts to get you interested:
Ganglionic intelligence:
Alien cultural universals:
Alien emotions:
… and more.
The ganglionic intelligence reminds me somewhat of Watts’ Thing (link to his short story)