ImaAtheistNow

Are the non-materialists arguing that if we completely remove an animal's brain, that the animal would still have memories and could still think?

fromderinside

I think Spamandham responds quite well to the physical nature of 'memories'

Most of the other dialogue seems a bit speulative, and at times, a bit off the main stream.

It might be worth a bit of time to see where 'science' is, actually, with respect to memory. Since the late sixties we've known about the role of the limbic system, particularly the hippocampus and memory maps or place memory. In fact most studies point to relationships between specific limbic structures and particular types of memory. The following few publications are particularly instructive and illustrative of where we are in understanding memory as a physical process located very specifically and functionally within the brain. First we look at cortical behaviors of mirror cells which are realted to both intention and memory.

Since I'm new to this forum I can't yet include links to articles underlying what I'm saying so you will have to take me at face value at present. The article: "Grasping the Intentions of Others with One’s
Own Mirror Neuron System" by Marco Iacoboni, Istvan Molnar-Szakacs, Vittorio Gallese, Giovanni Buccino, John C. Mazziotta, and Giacomo Rizzolatti's abstract reads a follows:

" Understanding the intentions of others while watching their actions is a fundamental building block of social behavior. The neural and functional mechanisms underlying this ability are still poorly understood. To investigate these mechanisms we used functional magnetic resonance imaging. Twenty-three subjects watched three kinds of stimuli: grasping hand actions without a context, context only (scenes containing objects), and grasping hand actions performed in two different contexts. In the latter condition the context suggested the intention associated with the
grasping action (either drinking or cleaning). Actions embedded in contexts, compared with the other two conditions, yielded a significant signal increase in the posterior part of the inferior frontal gyrus and the adjacent sector of the ventral premotor cortex where hand actions are represented. Thus, premotor mirror neuron areas—areas active during the execution and the observation of an action—previously thought to be involved only in action recognition are actually also involved in understanding the intentions of others. To ascribe an intention is to infer a forthcoming new goal, and this is an operation that the motor system does automatically."

Of course one needs to know how place and preparation are associated with the cortical areas described in the above article which is what this article is used to show. It reflects the importance of the hippocampus and place neurons in location memory. In their article "The Hippocampus, Memory, and Place Cells Is It Spatial Memory or a Memory Space?" Howard Eichenbaum, Paul Dudchenko, Emma Wood, Matthew Shapiro, and Heikki Tanila, write:

"The present conception of a hippocampal memory space provides an alternative to all variants of the cognitive map hypothesis in which space is the organizing principle. While rejecting the notion of a systematic and cohesive spatial mapping, the present review provides compelling support for the existence of place cells. Many hippocampal cells encode the locations where events occur, and the activity of some cells reflects the full topology of the environment independent of the animal’s behavior and nonspatial information. However, in our view, true place cells are simply an example of the nodal codings that can identify past episodes that share a common event—in this case, a “place” experienced in the past. In this conception, other nodal codings, including those for a particular stimulus, similarly serve primarily as links to past episodes and not as parts of a spatial map. Nor are they used to navigate, except in the sense that memories for previous places and paths taken, as well as for the events that occurred in familiar locations, are useful for navigation and other forms of inferential memory expression."


The most recently evolved limbic structure, the cingulate gyrus functions in memroy are both in terms of communication with frontal and motor cortical structures and it has been heavily implicated in intentional movement. The article "Autism, Asperger syndrome and brain mechanisms for the attribution of mental states to animated shapes" by Fulvia Castelli, Chris Frith, Francesca Happé and Uta Frith reflects fairly current status of knowledge about the relation between the motive system's cingulate gyrus and intentional movement through the study of autism.

In their discussion they relate: "Our able participants with high-functioning autism showed less activation than controls in three components of the mentalizing network: bilateral superior temporal sulcus at the temporo-parietal junction, the basal temporal area (left fusiform gyrus and right temporal pole adjacent to amygdala) and the medial prefrontal cortex. This last component also showed reduced activation in autism during ToM story comprehension in an earlier study by Happé et al. (1996), while lack of amygdala activation was found by Baron-Cohen et al. (1999) during a mentalizing task that involved eye gaze interpretation. Reduced activation in the region of the amygdala was also observed in subjects with autism while they processed facial expressions implicitly (Critchley et al., 2000).?


Linking these midbrain structures to frontal cortex are studies on Williams syndrome where individuals have a genetic conditon which results in inability to determine trust in facial expressions and where there is a missing pathway between the associated frontal cortex and amygdala as a review of recent work from the NYTimes health feed "The Gregarious Brain by
DAVID DOBBS makes clear

"The most significant such finding is a dead connection between the orbitofrontal cortex, an area above the eye sockets and the amygdala, the brain’s fear center. The orbitofrontal cortex (or OFC) is associated with (among other things) prioritizing behavior in social contexts, and earlier studies found that damage to the OFC reduces inhibitions and makes it harder to detect faux pas. The Berman team detected a new contribution to social behavior: They found that while in most people the OFC communicated with the amygdala when viewing threatening faces, the OFC in people with Williams did not. This OFC-amygdala connection worked normally, however, when people with Williams viewed nonsocial threats, like pictures of snakes, sharks or car crashes."

A fairly clear picture is emerging. Cells are located for various functions of memory, relations between memroy and intention are draw,and a fairly compelling arguement is developed for evolution of various types of memory were enabled as we evolved.

Steviepinhead

Plutopowered, you provided the following quote yourself, but seem not to have taken it fully on board:
My emphasis.

Look at the highlighted wording, which definitely suggests that memories are "made" of strengthened connections between particular neurons. (Otherwise, the little electrical wire-probes used by surgeons and researchers couldn't evoke a particular memory or association.) Some of these connections may only "contain" one aspect of a memory -- an associated word, image, color, smell, face, or name. Other connections in other specific locations contain other information, such as place or sequence with other associated memories. The hippocampus plays an important role in pulling the whole "picture" together from these scattered elements.

We know that certain brain areas are associated with certain functions, like Broca's area and language, or the back of the brain, where different visual processing functions are performed. So maybe a memory of your big wheel trike consists of assembling the right colors and shapes from the rear brain's visual processing centers and connecting them with the words "big wheel" from Broca's area and with a pleasant sense of childhood nostalgia from some other part of the brain.

And, in general, brain neurons do last for twenty or more years, even a lifetime (though they were long thought not to regenerate from certain kinds of damage, this is proving to be an overgeneralization -- the brain can, in certain situations and if provided with the right stimuli and therapy, "rewire" around damaged areas). I'm sure the molecules making up those neurons "turn over" over with the passage of time and the usual kinds of cellular maintenance, but essentially the "same" cell sits in the "same" place for a goodly period.

But, yes, if certain parts of the brain are damaged severely enough, then certain kinds of function can be lost. Word-labels (nouns and verbs) can no longer be correctly connected to visual shapes. The face may be recognized and remembered fondly, but the name that goes with the face is gone. A four-legged animal (horse) may be displayed, but the connection identifying which particular familiar four-legged animal it is may be lost, and the answer may be a hesitant "camel" or "lion."

Sure, as has been said several times, we may not yet have the complete picture (even your big wheel memory is but a pale ghost of the real thing, however vivid), but we're getting there with rapid strides. That doesn't leave a lot of room for metaphysical speculation that thought, memories, and consciousness reside, in whole or part, "elsewhere" than in the cells, tissues, and interconnections of the central nervous system.

Plutopowered

So, where does Quantum Physics / Mechanics fit into all of this? I thought that this was a current theory where consciousness / memories / thoughts which said that these things were "non local" to the brain.

Steviepinhead

That is, I believe, the not-so-widely-accepted claim of Roger Penrose, a brilliant mathematician. But not a neuroscientist or, as far as I know, a quantum mechanical physicist.

That "free will," "consciousness," or decision-making somehow require the quantum tumblers to spin like the cherries on a slot machine seems an unnecessary frill. Neural networks can "learn" and "decide."

Betenoire

Whose theory is that?

Plutopowered

For lack of a better reference...



But I thought this also encompassed the idea that consciousness / thought / memories aren't really stored in the brain as Quantum "stuff" can be in many places across the universe at the same time? Hinting that things which appear in the brain may not be necessarily stored there.

Maybe it's not as strong a theory as I thought.

fromderinside

Really?

I'm a bit amused that anyone can come to such a conclusion when somewhere at some time the objective for our genetic predecessors was to swim without a swim bladder, or pass through the digestive system of some other species.

Where does one come to ideals outside bodies from bumping into erratic conditions over evolutionary time?

Perhaps it happens. It certainly isn't some ideal unified thing? Or is it.

It isn't.

Without routes from amygdala to lateral frontal cortex humans don't understand approval (Williams Syndrome genetics research); without routes from cortex to hippocampus modelling movement and intentional movement are not properly carried out (Autism studies).

Both of these studies link to place, intention, and mirror cellular solutions originating in mid-brain.

We may be analogised by computer and quantum theories but the facts on the ground (that's for those of you who still give a heck about our spending cash to nation build in the ME for oil) are patch this, cobble that, over species time.

I'm totally aware that there are classes of molecules that tend to organize and this may be a continuing aspect of what is the physical universe. So at the glia cell level dopamine or some other transmitter may be the operator for some quantum machine that underlies the execution of memory found in intention, mirror, practiced movement, and place finding.

Just a couple thoughts.

Thanks for your consideration.

charles brough

May I suggest an entirely different approach to the problem? I see the neurology involved in the tracing of neural paths and the connecting of that with the hormonal system, but as far as determining human social behavior, I propose that a better approach is to simply list social traits as "instincts" with the clear understanding that they have to be and always are "conditioned" by culture. I like this approach not only because it is easier but also that it enables us to better understand human social nature.

Of course, there is the problem of what that nature is since it is conditioned differently by each culture. . . What I have done in my work is to research the extensive accumulation of data on the social behavior of chimps and other primates. When we dispense with the different terminologies we use for their behavior, it is remarkable how similar we are. Of course, our females do not "present" and our males no not go into rut, but there is still so much other social behavior that corresponds to our own as to give us an excellent picture. Keep in mind that we have about the same gender dimorphism as do the chimps . . .

Because of religious and even the secular ideals we share, it is necessary to be objective---even atheistic or non-theological---and dismiss concern over what is "politically incorrect.

Proceeding cautiously with that in mind, most primate groups center around a dominant male who, with chimps, aggressively watches over the territorial border. This provides security for the females and the offspring. If the alpha male is not aggressive and dominant enough, females will leave the group and go find one that is. The social science consensus is that mankind has never had a female dominated society. This would indicate that we also expect a male conductor with the orchestra, choose male presidential candidates, and also that females have a lot of stress when they have no respect for their nation's leadership. And finally, it means that the male sense of responsibility and protection of the group is the real basis for the responsibility exercised by the alphas and the courage which are, I think, mislabeled "altruism."

Other social instincts include reciprocation, and it lies at the very foundation of our economic system.

charles
http://atheistic-science.com

charles brough

I clicked the edit button to remove the HTML but my post was posted with it anyway.

charles