Monthly summary of general news, case histories,
and introductory articles about neurofeedback
for the interested layperson
Vol. 8 No. 8 - August 2005
Past issues are available at start.eegspectrum.com/News/
Copyright (C) 2001 by EEG Spectrum International. All rights reserved.
|
|
|---|
All links at news.yahoo.com/fc/Science/Brain_Research
In 1989, besides occasionally hanging out at Lilly's house in Malibu, I flew out to Hawaii to work with the other (and current) giant in the field of dolphin cognition, Lou Herman. I eventually switched back to humans, as you know (EEG), but there are a lot of advantages to dolphin cognition research that I miss. Albeit the pay is not good, but everyone is in bikinis and the tanks are at the beach. Herman's was adjacent to Waikiki Beach. Not a bad place to spend a lifetime.
So what does dolphin consciousness has to do with neurotherapy? Nothing directly, though Aquathought and other companies have disabled kids swim with dolphins for treatment. Some believe the dolphin's high-frequency pulses in the water improves the kids, a sonic-driven frequency entrainment perhaps. I think it's the realization that something (someone) far more powerful than you is not only not dangerous, but wants to play with you. It's our century's version of wrestling with angels.
This is August, the month of vacation, and vacating the normal path is what we do this month, so let me vacate the normal path in this newsletter. It's all part of the creative process, so instead of thinking what it is to be you, think what it is not to be you. What if you spent your entire life bathed in sound and water, like our large-brained aquatic brethren? What would your mental life be like? Would you, like a few on the radio show I was on (Virato live! - http://www.newfrontier.com/asheville/the-revolution.htm) claim that you were in telepathic communication with people? I wonder, or would you be smarter than that....
(The) belief that mental experiences are a unique attribute of a single species is not only unparsimonious; it is conceited. it seems more likely than not that mental experiences, like many other characters, are widespread, at least among multicellular animals, but differ greatly in nature and complexity. -- D.R. Griffin, 1981.
The largest brain ever to evolve belongs to the Cetacean order, home of dolphins, killer whales, and the largest dolphin of them all, the sperm whale (Physeter catodon) whose brain can weigh up to 9.2 kg Ridgway, 1986). Lilly (1967) argued that such a brain must produce consciousness exceeding our own, but most scientists note the very low brain-to-body weight ratio of the sperm whale, below that of a cow, and are left wanting. But if there is anything I know about the brain it's that the relationship between brain and mind is not an obvious one, and consciousness is no exception. Our form of consciousness -- representation of one's own mentation -- probably emerged during historic times (Jaynes, 1976; Snell, 1953), but features of self-awareness may be prevalent in other mammals, especially those with the extra neural hardware such as apes, carnivores, elephants, and whales.
Cetaceans are secondary aquatic mammals who, with the sirenians (manatees), are the only terrestrial mammals that have made a complete transition back to living in the sea. Dolphins evolved from a species that foraged in coastal waters until finally adapting to a complete life in the sea 50 or so million years ago. Once in the sea, they hit an ecological jackpot -- encephalization (large braininess) developed rapidly, surpassing all others as early as 15 to 25 million years ago. That is, until we came along. Much of what we know about cetacean neuroanatomy and neurophysiology comes from research performed on the Atlantic bottlenosed dolphin (Tursiops truncatus). Tursiops demonstrates great flexibility in vocal and physical behavior, and is believed by many to be the most intelligent cetacean. The resemblance of the dolphin brain to the human brain is unsettling at first sight (see Figure 1 and 2, online). Its great size and convolutions were noted centuries ago (John Ray, 1671). Tursiops has an average brain size of 1587 g while Homo sapiens average below 1400 g (Ridgway, 1986a). Encephalization quotients (EQ) which takes into account an animal body size --, a neuroanatomical IQ of sorts -- are nearly double that of apes, and are higher than any other mammal, except one
A dolphin's is most convoluted brain we know of, having more surface area per volume than even our own brains, nearly twice our surface area (Ridgway, 1986). But their cortex is relatively thin, about half of ours (1.3 compared to 2.9 mm at its thickest) so despite greater mass, the dolphin cerebral cortex is 560 cc compared to human's 660 cc. Not bad, considering that no other species comes so close.
Evolution, like good film directing, is about slowing events down, letting development proceed over time, retarding progress until a new fruition is had. Prolonged youth is not only the goal of many Americans, it is the goal of the evolution of intelligence. Time is needed for brain expansion, time to learn. Most mammals are born with up to 80 % of the full adult brain weight, but our neonates possess only a quarter of the final product and take two decades of growth before reaching the final weight. Tursiops is born with 43% of its final goal and takes a decade to reach adult levels, a pace that places them above most apes.
As I said in the radio show, not to put a downer on our dreams, but humans are probably the most intelligent species on the planet. Sad, but true. I didn't always think this, and would love if some pan-dimensional creature could take over terrestrial governance once in a while, maybe drive down the deficit and get us out of Iraq, but the other radio show guests didn't take a shine to any denigration of cetacean intelligence, least of all coming from a primate. One of the guests had experienced telepathic communication with a pod of dolphins in the past so she knew I was wrong....Well, some investigators argue, downingly, that the increased neocortex in marine mammals IS something to sneeze at. Large swimming brains do not imply the same thing (higher intelligence) as do large brain ashore. Deep diving (prolonged hypoxia) could require more cortical wiring (Wilson, 1933, cited in Ridgway, 1986a), or the neural wiring could be metabolically less active (probably not true) or the lack of REM sleep makes the wiring less efficient, such as with the echidnas (probably true). Or echolocation needs more wiring for the same bang-to-buck ratio of sight or smell. This argument might fly, but if the billions of echolocating small-brained bats didn't.
Size is not everything. When it comes to brains and most everything having to do with energy, organization beats out. The cetacean brain resembles the layout of the earliest mammalian (insectivore) brains, partly because that is when these creatures split from the terrestrial genome, and this suggests some gross primitiveness, but they boast more neocortex than us, 97.9% to 95.9% (Glezer, Jacobs, & Morgane, 1988). Yet still the cytoarchitecture appears conservative, relatively agranular or dysgranular, lacking laminar layer IV except for the presence of an incipient layer here and there. Tursiops neocortex is dominated by phylogenetically older layers I and VI, with an accentuated layer II due to layer I inputs with no true "Betz" cells present. The largest neurons tend to be in the pyramidal cell layers, III and V, and these neurons do not show the wide variations in size compared to terrestrial mammals - okay, okay, enough of the neuroscientific speak... so... overall their brains are white bread and mayo -- monotonous.... paleo-archicortextual. For instance the columnar organization in visual areas are larger and fewer than half the number of homologous structures in humans. Cytoarchitectonic analysis reveals only "prokoniocortex" (rudimentary layer IV), with no signs of koniocortex or parakoniocortex.... hey, it's hard to stop the sci-talk once one starts.
According to Morgane, Jacobs, and Galaburda (1985), cetacean neuroevolution arrested at a paralimbic/parinsular stage. In other words they returned to the sea before the latest upgrades in sensory and motor processors. So they are running DOS while we are running Windows (which would explain our problems... more of us need to run Macs). Neuroevolution progressed via replication, more and more of the same modules, instead of differentiation. But one should keep in mind that the rules governing neocortical organization are obviously different in Cetaceans than in most mammals. Idioadaptations -- specific changes in reaction to unique environmental pressures (an aquatic existence, for instance) -- have occurred.
Despite any apparent structural primitiveness, cetaceans demonstrate hemispheric specialization and hemispheric independence. Dolphins typically have a "viewing eye", usually a right eye preference for viewing strangers and novel stimuli. The optic chiasma is completely crossed in cetaceans so that such viewing indicates an initial left-hemisphere (LH) inspection during encounters, and each eye can act independently (disconjugatedly). Morrell-Samuels, Herman, and Bever (1988) demonstrated cognitive lateralization in sign-language-trained Tursiops, a LH advantage for processing complex signs and a RH advantage for simple gestural commands (not unlike the human pattern). Initial presentations of gestural commands result in a right-hemisphere advantage in reaction time which is slowly replaced by a LH advantage with subsequent presentations. Again, paralleling human findings. Cetaceans also demonstrate the greatest example of hemispheric independence, unihemispheric sleep: when one hemisphere is asleep (in stages 1-3) the other hemisphere is always awake, displaying desynchronized EEG patterns, often with one or both open eyes, (Mukhametov, Supin, and Polyakova, 1977). Cetaceans are voluntary breathers and bihemispheric sleep, which can occur in dolphins only under anesthesia, if prolonged, results in drowning. Most dolphin species show only short bursts of REM sleep, so our aquatic angels (or fallen angels) do not dream... hmmmm. Another unusual property is their relatively small corpus callosum, smaller in proportion than nearly every other mammals', about a fifth of our own.
Primate intelligence evolved to solve social problems (Cheney and Seyfarth, 1990) and was only later extended to nonsocial problems. The evolutionary significance of consciousness, or reflective introspection, or internal awareness, lies in the insight it provides the possessor about the (predicted future) behaviors of others. All mammals may be conscious of different aspects of their world, from proprioceptive body awareness to awareness of social agency (Crook, 1983), however the extent of consciousness in humans may be an idioadaptation to a hyper-complex social environment. The social behavior of Tursiops may not be as developed as that of higher primates (J. Mann, pers. comm.), but we are both social predators and intraspecial conflict is common in dolphins so they may have developed similar representations of mentation to survive.
Dolphins do show some signs of self-awareness. For instance, punishable behaviors are often performed only when a dolphin believes no one is around (e.g., Savage-Rumbaugh and Hopkins, 1986). When a dolphin squirts water at a human to show annoyance, he often raises his head out of the water to curiously observe the effect his behavior had on the unsuspecting victim (personal observation). Dolphins also have voluntary penile erections, which may suggest that they are conscious of things of which humans are not.
But anthropocentric definitions of consciousness (e.g., self-nonself and public versus private distinctions) may not be entirely useful for understanding the mental life of a cetacean. Tursiops are specialized for acoustical processing and probably structure the world acoustically more than visually. Objects are most real when based on auditory data. Whereas dogs and cats are smell brains, humans mostly sight brains, dolphins are mostly sound brains. Tursiops have echolocation and four other vocalizations and this co-occurrence of communicative and perceptual processing in the same modality may be their strength and weakness. Dolphins may be unable to distinguish between their sonar and another's communications (Lilly, 1967). The public nature of echolocation broadcasts and echoes may also result in shared perceptual information to such an extent that self-nonself boundaries are functionally meaningless. A perceptual world constructed of shared raw data might permit an intensity of group cohesion unimagineable to humans, or any primate for that matter. A dolphin may include others as part of his or her "decision-making unit" or self (a "group mind", Jerison, 1986). This could help explain widespread observations of reciprocal and inter-species altruism, a phenomenon once believed by many to belong to humans alone. Whatever cases are made for or against dolphin consciousness, it is interesting to remember that they as a species have had this ability perhaps a hundred times longer than we have (200 K years compared to 25 million).
Addendum: I ended my radio appearance with a brief mention of the Aquatic Ape hypothesis of human evolution. We Homo sapiens sapiens, the remaining branch or twig in the bushy hominid line that began in Africa and which we eventually outslugged or outreproduced or outweathered until all but us remained alive on this planet, we likely went through an aquatic phase of our own, not unlike dolphins. We are voluntary breathers, a trait shared by only marine mammals and no terrestrial ones. Our relative hairlessness, the distribution of the hair that remains, and our fat distribution under the skin (blubber to keep us warm) all suggest a semi-aquatic stage in our evolutionary past. A hundred thousand years ago or so a village or two of humans took to coastal waters like dolphins had done millions of years before and eventually a few of the neighbors' kids learned to control their breathing and swim longer and underwater, thereby opening a once unlimited and untapped resource. This new ecological niche, and the fish oils that came with it, may have fed the hungry growing brain, allowing all this new behavioral flexibility in the first place. Perhaps it was in water where a few of us refined our sound production techniques, and then brought these skills back to the home fires at night. Perhaps coastal living is in our genes. That would certaintly explain our penchant, and the high prices, associated with living at the shore.
-DK
News & Reviews
NEW BOOKS
Mind, Stress, and Emotions: The New Science of Mood
by Gene Wallenstein
Genetic, biological, psychological, and environmental bases of emotions, with novel treatment strategies for mood and anxiety disorders.
Brain Lock : Free Yourself from Obsessive-Compulsive Behavior
by Jeffrey M. Schwartz
Self-treatment druf-free program for obsessive-compulsive disorder
Addictive Thinking: Understanding Self-Deception
by Abraham J. Twerski
Case studies that reveal irrational and contradictory patterns of addictive thinking.
Everything Parent's Guide To Children With Add/adhd
by Linda Sonna
Child psychologist Sonna provides answers and information about signs, symptoms, and treatments of ADHD.
Exposure Treatments For Anxiety Disorders
by Johan Rosqvist, Michel Hersen
New book on exposure treatment.
Sleep And Sleep Disorders: A Neuropsychopharmacological Approach
by Malcolm Lader
New book on the neuropsychopharmacological of sleep.
Executive Function In Children, Adolescents, And Adults With ADHD
by Weyandt
Executive deficits in ADHD are not gender-specific, persist, and often are not accounted for by intelligence or comorbidities.
The Addiction Counselor's Desk Reference
by Robert Holman Coombs, William A. Howatt
Comprehensive resource on the spectrum of addictive disorders, their consequences and treatment.
Handbook of Disruptive Behavior Disorders
by Herbert C. Quay, Anne E. Hogan
Three quarters of all psychopathological disorders of childhood and adolescence are disruptive behaviors (ADHD, ODD, CD). Reviews various issues of this disorders including assessment.
Fibromyalgia and Chronic Myofascial Pain
by Devin J. Starlanyl, Mary Ellen Copeland
Latest medications, tips for bodywork, and suggestions for coping with family, work, and dealing with healthcare.
Handbook of Emotions, 2nd Edition
by Michael Lewis
From the philosophy of emotions to emotions in art and the humanities to emotions in the mammalian brain and facial expressions.
Cognitive Electrophysiology of Mind and Brain
by Alberto Zani, Alice Proverbio
Reviews developments in recording of bioelectric and magnetic responses of the brain.
Neurotransmitters, Drugs and Brain Function
by Roy Webster
Textbook for students of pharmacology, psychology, neuroscience, and related disciplines.
Attention Deficit Hyperactivity Disorder: From Genes to Patients
by David Gozal
Discusses the genetics and recent research in clinical neuroscience on ADHD
Surgical Treatment of Epilepsy
by Josef Zentner, Wolfgang Seeger
Overview on different surgical methods.
ARTICLES
The course of neuropsychological functions in children with ADHD
:
ADHD differences are most pronounced before adolescence. The developmental course of components of attention must be considered in diagnosis.
Sequential magnetic resonance imaging follow-up of multiple sclerosis
:
Time course in single MS patient over three years as MS developed.
Integrative assessment of brain and cognitive function in post-traumatic stress disorder.
:
PTSD shows delayed N2 latency and reduced P3 target amplitude, with strongest effects over the left hemisphere.
Neural networks of information processing in posttraumatic stress disorder
:
Enhanced anterior cingulate responses in PTSD, regardless of threat, was found, suggesting reflect generalized hypervigilance.
Psychiatric and substance use disorders in late adolescence
:
Differences in risk and social support were assessed in youth for anxiety, drug problems, and controls.
EEG biofeedback in the treatment of ADHD
:
Clinical improvement was reported in three-quarters of ADHD patients, but more controlled group studies are needed.
Nociceptive processing in the human brain.
:
Discusses the future of nociception investigations using neuroimaging.
Fronto-Limbic Brain Abnormalities in Juvenile Onset Bipolar Disorder.
:
Pediatric bipolar disorder children exhibit smaller amygdala volumes compared to controls, contrary to adult studies.
Personality traits and its association with resting regional brain activity.
:
Some associations are found between delta and theta activity across cortex with Extraversion and Conscientiousness but few associations were found for alpha and beta activity.
Alcohol on neuropsychological functioning of abstinent cocaine-dependent subjects.
:
Alcohol may reduce some of vasoconstriction/neurotoxic effects of cocaine, accounting for the fewer memory deficits than expected.
EEG evidence for mirror neuron dysfunction in autism spectrum disorders.
:
Following the idea that mu activity (8-13 Hz) over sensorimotor cortex reflects mirror neuron activity, high-functioning autistics showed mu suppression to self-performed hand movements but not to observed hand movements.
Prevalence, course and clinical features of post-concussion syndrome in children.
:
One year after trauma, prevalence of post-concussion symptoms are similar to mTBI children.
Long-term stability of frontal EEG asymmetry in depression
:
Alpha asymmetry was moderately stable in depressed and normals individuals (intraclass correlations between 0.39 and 0.61).
EEG mapping and LORETA in diagnosis of psychiatric disorders
:
Low-resolution brain electromagnetic tomography identifies brain regions affected by psychiatric disorders and psychopharmacological substances.
Cannabis-related problems
:
Cannabis problem users are more likely to be male, single, under age 20 and in high school.
Psychiatric Disorders in Individuals with Pervasive Developmental Disorder.
:
Individuals with PDD are at risk for various psychiatric disturbances, including affective and anxiety disorders, aggression, antisociality, and Tourette's.
Impaired self-awareness after moderately severe to severe traumatic brain injury.
:
Patients may underreport residual cognitive and behavioral impairments from brain injury.
rTMS in treating OCD and Tourette's syndrome
:
Normalization of right hemisphere hyperexcitability was observed after just the first week of rTMS treatments.
Influence of Age, Gender, Health Status, and Depression on Quantitative EEG.
:
Prefrontal cordance in theta activity, independent of demographic variables, was associated with pathophysiology of depression and response to treatment.
Treatment of alcohol use disorders in adolescents.
:
Authors stress the need to target comorbid psychiatric conditions, notably anxiety and depression.