The “mind-body problem” is alive and well. Can these phenomena be reduced to matter in motion?
Babies feel pain like adults do: We all know that pain is more than just a conditioned response; it hurts! A press release from the University of Oxford took brain scans and found that babies’ brains light up during pain with similar patterns as adult brains, suggesting they experience pain the same way. Incidentally, an important vote is going on in Congress on a law that would restrict abortions for “pain-capable” babies in the womb (see FRC News). Tony Perkins of the Family Research Council says “this legislation conforms federal abortion law to modern science.”
Hearing between the ears: How does the brain balance hearing coming from two sources? Science Daily reports that scientists at the University of New South Wales (UNSW) have determined part of the answer: it has to do with the “olivocochlear reflex” —
“Our hearing is so sensitive that we can hear a pin drop and that’s because of the ‘cochlear amplifier’ in our inner ear. This stems from outer hair cells in the cochlea which amplify sound vibrations.”
“When sound intensity increases, the olivocochlear reflex turns down the ‘cochlear amplifier’ to dynamically balance the input of each ear for optimal hearing, sound localisation and to protect hearing.“
The study found that the cochlear’s outer hair cells, which amplify sound vibrations, also provide the sensory signal to the brain for dynamic feedback control of this sound amplification, via a small group of auditory nerve fibres of previously unknown function.
The brain, of course, has to know what to do with this information that the mechanical and physical hearing organs deliver to it.
Motion blur compensation: Your eyes are constantly moving, and often, objects you see are moving, too. Why don’t you see a constantly blurred picture? The UC San Diego Health System has a partial answer:
Researchers at University of California, San Diego School of Medicine and Shiley Eye Institute have identified the molecular “glue” that builds the brain connections that keep visual images clear and still, even as objects or your eyes move. Using mouse models, the researchers demonstrate that image stabilization depends upon two proteins, Contactin-4 and amyloid precursor protein, binding during embryonic development. The study is published May 7 by Neuron.
Lead scientist and ophthalmologist Andrew D. Huberman discusses sensors and “precise connections” between neurons in the brain aided by these proteins. When these proteins are mutated, “the circuit didn’t form properly and visual cells didn’t talk to the brain correctly.”
Brain’s router: The brain’s “sorting and routing center” is discussed in Science Magazine. Environmental messages from the senses need to know where to go; how is this achieved? Researchers have found that the hippocampus does not send out general broadcasts. Instead, “hippocampal neurons route distinct behavior-contingent information selectively to different target areas.”
How do higher brain areas communicate with each other? Do they send out all computations equally to all target areas and leave the recipient to extract the needed and relevant information? Or does the transmitting region package and route computations differentially to distinct target areas, depending on the content? Ciocchi et al. found that the ventral hippocampus routes anxiety-related information preferentially to the prefrontal cortex and goal-related information preferentially to the nucleus accumbens. Hippocampal neurons with multiple projections were more involved in a variety of behavioral tasks and in memory consolidation.
Organizational principles: Without mentioning evolution, a press release from the Max Planck Florida Institute shows how its team created 3-D color models of neuronal interconnections in order to understand the “organizational principles of the neocortex.” Consider what transpires when a rat twitches a single whisker:
First, neurons of all cell types projected the majority of their axon – the part of the neuron that transmits information to other neurons – far beyond the borders of the cortical column they were located in. Thus, information from a single whisker will spread into multiple cortical columns…. Second, these trans-columnar pathways were not uniformly structured. Instead, each cell type showed specific and asymmetric axon projection patterns, for example interconnecting columns that represent whiskers with similar distance to the bottom of the snout. Finally, the researchers showed that the observed principles of trans-columnar pathways could be advantageous, compared to any previously postulated cortex model, for encoding complex sensory information.
Time code: The brain can even simulate time dilation and time contraction. A paper in Current Biology explores the “neural coding” itself can dilate and contract.
The brain is a time machine, of sorts. It is always attempting to predict the future. At this moment you are automatically predicting the next word in this ……. And given the dynamic nature of the world, the ability to tell time and process temporal information is critical for motor coordination, sensory processing, and the ability to anticipate environmental events.
Think about how a piano student can play the same piece fast or slow. How do the neurons adjust for the time differences? Some progress was made by Mello et al. in a paper in the same issue of Current Biology, but much remains unknown:
Nevertheless, the new study by Mello et al. is the first to provide clear evidence for a relative code for timing on the seconds to minute scale. The most fascinating question raised is how this is accomplished. How does a population of neurons temporally contract or dilate their responses? At the population level we can think of the firing pattern as a trajectory in N-dimensional space — where N corresponds to the number of recorded neurons. Thus, a relative temporal code corresponds to traveling along the same (or similar) trajectory at different speeds. In principle the simplest way to achieve such a rescaling is to scale the time constant of the neurons in circuits. There is, however, little evidence that such a mechanism is physiologically plausible. Another possibility is that tonic inputs or neuromodulators effectively control the dynamics of the circuits in a manner that scales the speed of the neural trajectory.
Because rats can robustly rescale their motor behaviors, and humans can easily rescale the speed with which they speak or play a musical piece, future studies will have to determine not only how the brain encodes time, but how it does so in a flexible manner that allows for time dilation and contraction.
Is anyone considering the possibility that the user of the brain tells the neurons what to do?
Unreal abstractions: PhysOrg asks a semi-philosophical question: “Can the brain map ‘non-conventional’ geometries (and abstract spaces)?” It’s an interesting question, because one would suspect that evolution would have no use for such abstractions; it needs to tailor the organism to the real world. Nevertheless, research published by the Royal Society suggests that mammal brains are pre-equipped to comprehend hyperbolic spaces and non-Euclidean geometries:
Grid cells, space-mapping neurons of the entorhinal cortex of rodents, could also work for hyperbolic surfaces. A SISSA study just published in Interface, the journal of the Royal Society, tests a model (a computer simulation) based on mathematical principles, that explains how maps emerge in the brain and shows how these maps adapt to the environment in which the individual develops.
“It took human culture millennia to arrive at a mathematical formulation of non-Euclidean spaces”, comments SISSA neuroscientist Alessandro Treves, “but it’s very likely that our brains could get there long before. In fact, it’s likely that the brain of rodents gets there very naturally every day.”
Choosing not to be depressed: Is depression a disease of physical neurons? If so, it would seem curable by physical drugs. Science Daily, though, reproduced a press release from The Lancet that announces, “Mindfulness-based therapy could offer an alternative to antidepressants for preventing depression relapse.” Mindfulness therapy takes the reality of the mind seriously. In a controlled experiment, one group kept taking antidepressants, but the other group engaged their minds with “guided mindfulness practices, group discussion and other cognitive behavioural exercises.” Both groups had similar rates of relapse and success. One advantage of mindfulness-based therapy is cost: “As a group intervention, mindfulness-based cognitive therapy was relatively low cost compared to therapies provided on an individual basis and, in terms of the cost of all health and social care services used by participants during the study, we found no significant difference between the two treatments.”
The mind-body problem raises profound philosophical and theological questions. How does the realm of atoms and the realm of concepts interact? Which is predominant? Many books have been written on these questions, but the evidence cited here underscores the view of the human mind as a personal soul with free will. The neurons of hearing, sight and the other senses are servants to the self. For non-human mammals like the rats in the experiments, input from the senses is directed by the brain intelligently for adaptive responses (instincts), but think about the human cases. The piano student can choose to play a piece fast or slow; the neurons do not determine any instinctual response. We can all say “no” to our neurons and choose to take actions that at times are radically opposed to what our senses or instincts (if we have such things) pressure us to do. We can even blaze past the pain and do a courageous act that makes no sense in terms of safety or survival.
We further can tell that the soul is real, because in none of these research projects did the scientists act by instinct. Nothing in the presumed evolution of the human being gave survival value to writing a scientific paper, conducting a controlled experiment, or reasoning about the causes and effects of abstract geometric concepts on grid cells. It’s not surprising that each of the researchers was silent on the subject of evolution.
As for depression, it’s doubtful the researchers at Oxford gave spiritual comfort from the Bible to the patients in the mindfulness-based therapy group. If they gave them old-fashioned non-directive counseling and empty talk in group discussions, that would be highly unlikely to bring comfort except for the false comfort of shared misery. The gospel of Jesus Christ, however, is a well-spring of joy. Paul said, “Therefore, since we have been justified by faith, we have peace with God through our Lord Jesus Christ. Through him we have also obtained access by faith into this grace in which we stand, and we rejoice in hope of the glory of God” (Romans 5:1-2). What could be better for a depressed person than peace, grace, joy, and hope? In a real sense, depressed people are selfish. They’re thinking about themselves and their feelings: “Woe is me; I’m so sad, I deserve better.” The gospel takes our eyes off ourselves and onto our Maker where they belong. We all would be less depressed if we stood in this grace of God by faith, by trusting God’s promised Messiah, Jesus Christ, for “access by faith” into the glory of God.
Once a person is walking by faith in the joy of the Lord, grateful for forgiveness and a new life, a whole new world of joy just begins. Think about these wonders of science mentioned in this one article: projection neurons that connect precisely to give you clear vision, outer hair cells in the cochlea that automatically balance the inputs from your two ears, organizational principles, time codes — He made these all for you, so that life could be richer, that you might look up and share His great love. I guarantee you will find it hard to be depressed when your response to these facts is, “Wow! That’s amazing! Thank you Lord! I love you, Lord! Your awesome power and wisdom is incomprehensible; it’s beautiful—Hallelujah!”