Sentience: the capacity to feel, perceive or experience subjectively; the ability to experience sensations, known in philosophy of mind as qualia; (this may not be true: “sentience appears at a certain stage in humans, as in other species, and brain damage can result in those abilities being lost so not all humans are sentient”)
Mind: the element or aspect of a person that enables them to be aware of the world and their experiences, to think, and to feel; the faculty of consciousness and thought, including abstract thought about things not directly sensed by human senses such as sight, touch, smell or hearing
The February 2020 issue of Scientific American includes an article, In Search of The Brain’s Social Road Maps. The article summarizes research that is beginning to describe how the brain and mind might work in terms of monitoring and guiding our movements in space and time, social relations, memory and abstract thinking.
The concept of cognitive maps as a part of the workings of the mind arose in 1948 in experiments with rats that generated data interpreted as rats being able to think abstractly. The data was fully consistent with a brain that could think in terms of locations in space without having physically been to the locations. That was seen when rats knew how to navigate a maze they had never been through.
Later research discovered neurons in the brain that helped keep time, which facilitated mapping of space. The brain maps are little clumps of neurons (place cells) that fire together when sense inputs or abstract thinking lead to known locations. Three clumps of neurons (grid cells) constitute triangles corresponding to a known place. When a known person is encountered a 2-dimensional map for that person is activated with the perceived power of the person and their social closeness being the two axes. Place and grid cells are now hypothesized to play a role in creating social maps. If that is true, then the human mind creates maps for both places in space and the social position of other people relative to the observer.
The Jennifer Aniston Neuron
Our brains create concepts or images of other people they know. Specific neurons are involved. The authors write:“The progression from the physical to the abstract carries over into the way the brain represents social relationships. Various bits of knowledge about another person are distilled into the concept of that individual. When we see a photograph of someone or hear or see that person’s name, the same hippocampal cells will fire, regardless of the sensory details of the stimulus (for example, the famous “Jennifer Aniston neuron” described by Itzhak Fried of the University of California, Los Angeles, and his colleagues). These hippocampal cells are responsible for representing concepts of specific individuals.
Other hippocampal cells track the physical locations of others and are called social place cells. In an experiment by David Omer of the Hebrew University of Jerusalem, Nachum Ulanovsky of the Weizmann Institute of Science in Rehovot, Israel, and their colleagues, bats observed other bats navigating a simple maze to reach a reward. The task of an observer bat was to simply watch and learn from a navigating bat, enabling it to subsequently navigate the same route to get the same reward. When the observer bat watched, hippocampal cells fired corresponding to the location of the other bat.
Hippocampal activity also tracks social hierarchies: the demands of a boss and a co-worker, for instance, may be valued differently and confer different social standings. Common metaphors illustrate the spatial dimensions of a hierarchy: a person may try to gain status to “climb the social ladder” or “look down” at someone below them. Other factors are also critical. Biological relatedness, common group goals, the remembered history of favors and slights—all determine social proximity or distance. Human relationships can be conceived of as geometric coordinates in social space that are defined by the dimensions of hierarchy and affiliation.”
Thus if bat and human brains work alike, they commingle map information about space and time with images of the social power vs. closeness map location of others. Experiments can follow human brains in space and time as they form various social relationships with characters in computer games. Evolving human relationships in these games can be plotted as trajectories through social space, giving data on angles and lengths of the social vectors our brains create.
The world is too complex, we need to model and map it to simplify it
What all this appears to boil down to is this: The world is too complicated to deal with directly. We cannot test all possibilities in life, so we need some way to think abstractly about them. That avoids the need to test many possibilities without ever directly experiencing them. To simplify and model reality, our brains use clusters of neurons to create and represent physical maps of space, time and other people. Using that information our brains can recall memories, think abstractly and come to new insights and beliefs about their physical and social situation without directly experiencing reality. Maybe this sort of exercise in reviewing and making maps is the basis of consciousness and/or sentience for humans, and possibly other animals.
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