DOES AN OCTOPUS HAVE A HIPPOCAMPUS?

Sy Montgomery’s book, “The Soul of an Octopus”, is both seductive and astounding and yet it only describes close interaction with the creatures in an aquarium, the latest target for PETA.  Reading this story will convince a person that just eliminating aquaria is a dumb idea, like forbidding artists to paint pictures, but also make it clearly imperative to protect captured creatures with diligence and understanding.  I’m going to quote quite a bit to keep from being inaccurate.

The understanding part is not easy.  These octopuses (mostly Pacific Giant species), scary as they can be, have followed such an entirely different evolutionary path that our assumptions can’t possibly fit, and yet interacting directly with them feels personal, both in their impact on the human and in the projection of individuality from each of them.  They’re quite distinct from each other.

An octopus has no brain like ours, though their “head” has “eyes” quite a bit like ours.  Each tentacle has its own brain and can continue to live when separated, at least for a while.  The nose/mouth complex of a human (taste and smell) is in each suction cup ranged in rows down the arms: they taste with those suction cups but also can vary the suction through a little hole in the center and can fold themselves enough to pinch up small things, one cup separate from another.  When they are handed the little fish or crab they eat, they accept it at the tip of the tentacle, and then pass it down the “arm” to the mouth which is a venomous beak.  Their siphon can blast a person with water.  When they “ink” with a cloud of obscuring darkness, they need to leave because it will suffocate them as well as their enemy.

Sy explores all this with adventures, including her own struggle to learn to scuba dive, and with her empathic reaching out and sharing the reaching out with others.  She picks up on a multi-armed starfish that lives in the same tank as the octopus and which has NO BRAIN AT ALL, but constantly tries to sneak over to steal the octo’s fish, except that it gets hosed with a blast of water from the octo.  It has no eyes, nor ears, so it must be picking up its sensory information from molecules in the water or maybe vibrations.  The starfish is “thinking” — or at least reacting — with its whole body.

Sy likes chickens, too.

Somehow, that’s easier to understand than eight brains.  How do they interact to achieve consensus?  Sometimes it has been observed that an octo seems to have dissension in the ranks: some arms want to retreat and some arms want to advance.  Octo’s also have favorite tentacles, something like being right-handed.

From wikipedia:  “Fish intelligence is "...the resultant of the process of acquiring, storing in memory, retrieving, combining, comparing, and using in new contexts information and conceptual skills" as it applies to fish.  According to Culum Brown from Macquarie University, "Fish are more intelligent than they appear. In many areas, such as memory, their cognitive powers match or exceed those of ‘higher’ vertebrates including non-human primates.”  All bony fish have a hippocampus.

Bony-eared assfish

They hide -- wouldn't you?

“Fish hold records for the relative brain weights of vertebrates. Most vertebrate species have similar brain-to-body mass ratios. The deep sea bathypelagic bony-eared assfish, has the smallest ratio of all known vertebrates. At the other extreme, the electrogenic elephantnose fish, an African freshwater fish, has one of the largest brain-to-body weight ratios of all known vertebrates (slightly higher than humans) and the highest brain-to-body oxygen consumption ratio of all known vertebrates (three times that for humans).

Elephantnose fish

The fancy language (bathypelagic and electrogenic) refer to the depth in the ocean they occupy and what their source of energy might be.  By the time discussion turns to things like “electrogenic” the real subject is ions and atomic dynamics in molecules.  But those esoteric subjects are what explain how brains work, all those acquiring, storing, retrieving, combining, comparing and using functions, interacting through the various evolved cells and their structures.  

One whole category of research is called “the Hippocampal Indexing Theory.  It’s about those two little seahorse-shaped blobs just above the ears (inside— you can’t see them) which we’ve known for a long time are about memory.  This field of study wants to know how it is that a particular smell, slant of light, tone of voice, can summon up a strong memory of a whole situation.  So now I want to know whether an octopus has a hippocampus or eight hippocampuses or what precursor of a hippocampus might be like.  The animals clearly do remember.

PZ Myers, writing in “Pharyngula” says:  “We know that the octopus is amazingly smart. They are capable of associative and observational learning, they are curious and adaptive, and can invent new solutions to problems. They have a large brain relative to their body size, containing about 500 million cells, and they have condensed the classically distributed invertebrate central nervous system into a dense, discrete brain. One of the problems that stymied Young was that, rather than retaining the very large and accessible identifiable neurons we associate with invertebrates, the cephalopods have paralleled the vertebrates, microminiaturizing neurons to pack more cells into a given space. They’ve also built layered structures into their brains, and thrown the tissue up into folds that increase surface area, much as the vertebrate cortex has.”

It appears that a part called the vertical lobe handles long-term memory, similar to the hippocampus.  “What does the VL do? Octopuses are tough and resilient, and as it turns out you can do some fairly invasive surgeries, stitch them up, and they recover just fine. The VL can actually be extirpated, and VLless octopuses, once they’ve got over the surgery, seem perfectly normal in swimming, feeding, and other ordinary behavioral functions. Deficits show up, though, when they are tested on learning and memory tasks: long term memory function is lost, and learning is greatly impaired. The VL and the median superior frontal lobe (MSF) together form a structure that is functionally analogous to the vertebrate hippocampus.”

The octopus eye is like ours except for a slot pupil.

“The findings emerging from recent electrophysiological studies in the octopus suggest that a convergent evolutionary process has led to the selection of similar networks and synaptic plasticity in evolutionarily very remote species that evolved to similar behaviors and modes of life. These evolutionary considerations substantiate the importance of these cellular and morphological properties for neural systems that mediate complex forms of learning and memory. In particular, the similarity in the architecture and physiological connectivity of the octopus MSF-VL system to the mammalian hippocampus and the extremely high number of small interneurons in its areas of learning and memory suggest the importance of a large number of units that independently, by en passant innervation, form a high redundancy of connections. As these features are found in both the octopus MSF-VL system and the hippocampus, it would appear that they are needed to create a large capacity for memory associations.”

Comparisons are a strong scientific method of investigation.  Odious as comparisons between the worth and accomplishments of people, including the scientists, may be, looking for difference and sameness can reveal much information.  So the octopus, which has evolved with no skeleton at all (it cannot develop Avascular Necrosis which in humans causes bones to disintegrate since it has no bones) might possibly reveal something about how to cure bone diseases.

The octopus named Octavia and her friends.

In the meantime Sy and her friends create attachment and intimacy with creatures pretty much like silk scarves afloat in sea water with long arms buttoned with rows of suction cups and eyes they can pop up out of their heads to look at us.  What they see makes them change colors and skin patterns, a sight-vocabulary that Sy learned.  The original divergence of species comes back together in a confluence of interactions.

EMBRACING THE OCTOPUS

Recently I’ve accumulated a little stash of quotes about identity, consciousness, reality, and our drive to understand what goes on in minds.  Some will be quite disconcerted by these suggestions and others will sigh with recognition.

This is a quote from Timothy J. O’Neill who posts on “Medium” which is an author venue, something like “Blogger.”  It’s a pretty good summary of a breakthrough in how we understand identity that might be summed up by the phrase, “Compose yourself.”  This comes from considering the atypical minds of persons around us.  It will offend those who define human thought as unified, consciously intelligent, produced by learning and interaction with a physical environment, demonstrated by language, and demanded by culture.

Doctor: “Our minds shape every aspect of our reality and, in turn, every aspect of our reality has the potential to influence and shape our minds. And not just our minds, but our brains, our material physiology. But the brain even has the amazing capacity to somehow alter itself. Neuroscience has proven your thoughts can physically restructure the organic matter of your brain. It’s as if a hologram could turn around and start tinkering with the projector producing it in order to change the color or clarity of its own image. Think about that for a moment, and then open yourself up to the idea that the power of past events to shape your present identity PALES in comparison to the power of your present thoughts. So what do you really want to focus on now?”

Another more radical effort to understand minds that are not necessarily human (aside from aliens in outer space) comes from the study of octopuses.  As it happens, there’s recently been a flurry of thought about octopuses because of the release of the complete genome that has taken several years to complete at the U of Chicago.  It appears that our brain are more like the the brain of an octopus than we might guess, but also radically different: the brain of an octopus is partly in its tentacles, whose suckers are both able to taste and to feel.

This article by Sy Montgomery in Orion magazine is called “Deep Intellect.”   https://orionmagazine.org/article/deep-intellect/   It’s an attempt to understand an octopus from the outside, actively interacting with several, but also noting the information we have about them.  Octopus eyes are seemingly just like ours in terms of anatomy, but what do their nerves in their retinas pick up?  And what do their main brain configure the information?  They are sensitive enough to mimic other animals or just a piece of coral, but is that conscious thinking? There’s a wide variation in temperament from one animal to the next. 

This is from a piece in New Scientist.  “THERE is no denying the reality of consciousness. For most of us, it is so self-evident that it requires no explanation. Your conscious self is the owner of your private reality, and your actions stem from conscious choice.

However, the more that is discovered about consciousness, the less obvious its role appears to be. For example, measurements of brain activity reveal that muscles and brain areas prepare for an action, such as a reaching out for an object, before we are even aware of our intention to make that movement. As noted by the psychologist Jeffrey Grey and others, consciousness simply occurs too late to affect the outcomes of the mental processes apparently linked to it.”

How much of ourselves is the result of our body structure?  (What a relief it would be to those who suffer from extremely painful avascular necrosis, bone death, to manage a body with no bones!  But how does one de-centralize a brain trapped in a skull?)  How do people become “unhinged?”

How much is learned?  How much is voluntary?  The answers are radically different depending on the method used to define and sort the problem.  This is one of the central issues of the U of Chicago Divinity School, because it is so relevant to comparative religion.  The confrontive, dominating, logic-dependent practice of Christian theology, its method, is a key element in the Pauline version of Catholicism.  Many have pointed out it is quite different from Jesus’ message of tolerance.

Using consciousness-altering drugs has not taught us much about method, though it IS one, but their exploration of inner space has certainly confirmed that the molecular alternatives in cell tissues can profoundly alter the way we see the world.  We already knew that from experience as far back as pre-hominids, but we’ve changed the way we think ABOUT them.  In this age of control some see using them as stepping away from the intolerable burden of being oneself in a world that despises who you are, and others who locate themselves by controlling whomever is different, and becoming lethal.

The octopus is a pluralistic animal in the sense that each tentacle has its own perceptions and decisions.  If a tentacle is severed and then offered a fish that its original task would have beem to convey to its mouth, it will try to convey the fish to where it thinks the mouth should be.  In our pluralistic policy we call democracy, many tentacles have been separated from the central mouth.  It’s an interesting and possibly useful metaphor.

The other startling thing octopuses do is cram themselves into impossibly small spaces.  Consider this quote from a paper in “Synapse,” (Volume 69, Issue 8, August 2015).  Unless you have the vocabulary, you will find it hard going, but the point of it is that what seems to be as personal as withdrawal to their room, like an octopus looking for a defensible space, can be associated with certain brain molecules, and might be predictive of trouble.

“Adolescent social isolation (SI) results in numerous behavioral alterations associated with increased risk of alcoholism. Notably, many of these changes involve the basolateral amygdala (BLA), including increased alcohol seeking. The BLA sends a strong glutamatergic projection to the nucleus accumbens and activation of this pathway potentiates reward-seeking behavior. Dopamine (DA) and norepinephrine (NE) exert powerful excitatory and inhibitory effects on BLA activity and chronic stress can disrupt the excitation-inhibition balance maintained by these catecholamines.” 

Some people will deduce that technical chemical diagnosis should be applied to all “withdrawn” adolescents and Big Pharma will set about inventing a med that affects BLA activity.  Others will try to eliminate all stress, assuming that emotional “gliding” is healthy.  They try to create a “no-trouble bubble.” A few will want to sit down and talk.  And nowadays, with the fortification of genealogy, some will want to investigate the ancestral stories of the individual to look for patterns.  For a person who has been convincingly told that any disclosure will result in punishment amounting to death, this is nearly impossible.

We keep seeing stories about teens being held in solitary confinement, framing the adolescent in terms of radical social isolation, his own head trip which can end in suicide. [http://www.nytimes.com/2015/06/09/nyregion/kalief-browder-held-at-rikers-island-for-3-years-without-trial-commits-suicide.html]

But some will think about what a supporting social setting will do and what kind of tribe would welcome and understand the individual.  One could call it “embracing the octopus.”  To get an idea what that might be like, try the Orion article.