Biopsychology • The scientific study of the biology of behavior. • It is a research intensive field. • New findings continually update our current state of knowledge. Pop Quiz: true/false 1. Everyone is born with all the neurons they will have throughout life, what changes are the connections between them. 2. When neurons of the CNS die they are not replaced. 3. Glial cells provide the ‘glue’ that holds neurons in place but do not directly communicate with other cells. 4. Paralysis from stroke is permanent with minimal functional restoration. Karl Lashley (1890-1958) • Coined the term “neuropsychology” • Studied the effects of cortical lesions on learning performance in rats with the goal of finding the “engram” or locus of a memory trace. • Principle of “equipotentiality” • Principle of “mass action” Phrenology • Franz Joseph Gall (~1800) • Personality traits can be determined by measuring protrusions or bumps on the skull. • Although the methodology was discredited as a pseudoscience, it did advance the idea that certain functions may be localized to specific brain regions. Multiple memory systems • Current research supports localization of function… • E.g., Different types of learning – Behaviorism (S-R) – Cognitivism (S-S) • Neuropsychological evidence compellingly demonstrates that different brain regions mediate cognitive and associative learning. Can one localize ‘intelligence’ Once thought to be the complex function of the prefrontal cortex, until… • Phineas Gage Can we localize intelligence within the brain? …or put another way, is the brain of a ‘genius’ different? Several publications have reported differences between Einstein’s brain compared to ‘normal’ control brains, which has led to some debate among scientists. References: 1. Diamond, M.C., et al. (1985). On the brain of a scientist: Albert Einstein. Exp Neurol 88, 198204. 2. Kantha, S.S., (1992). Albert Einstein's dyslexia and the significance of Brodmann Area 39 of his left cerebral cortex. Med Hypotheses 37, 119-122. 3. Anderson, B., Harvey, T. (1996). Alterations in cortical thickness and neuronal density in the frontal cortex of Albert Einstein. Neurosci Lett 210, 161-164. 4. Galaburda, A.M. (1999). Albert Einstein's brain. Lancet 354, 1821; author reply 1822. 5. Hines, T. (1998). Further on Einstein's brain. Exp Neurol 150, 343-344. 6. Salvatori, R. (1999). Albert Einstein's brain. Lancet 354, 1821-1822. 7. Seitz, J.A. (1999). Albert Einstein's brain. Lancet 354, 1822-1823. 8. Colombo, J.A., et al. (2006). Cerebral cortex astroglia and the brain of a genius: a propos of A. Einstein's. Brain Res Brain Res Rev 52, 257-263. 9. Falk, D. (2009). New information about Albert Einstein’s brain. Frontiers in Evolutionary Neuroscience, 1, 1-6. The brain’s brain - Princeton Hospital, Apr 17, 1955 The pathologist, Thomas Harvey is on call Hans Albert’s retroactive approval Harvey gets canned & moves to Kansas Will publish soon, then 30 years later… Looses license and wife but keeps the prize Early 80’s, finally some research The drive to CA, look what I have Drives back to Princeton – here, you take it… More research is done, 3 main pubs One pub worth a million $ Apr 5, 2007 – the fun ends Back home with Elliot Krauss Opthalmologist, Henry Abrams The End (or is it) A strange journey The brain-snatcher: Thomas Harvey The driver: Michael Paterniti The passenger: Einstein’s brain “Anticlimactic endings are like taking your dog for a walk only to watch him urinate on your rug when you come back home. Not that the walk itself wasn’t enjoyable, just that the end result leaves a lot to be desired.” Review: Horowitz, S. (2000). Driving Mr. Albert: A trip across America with Einstein’s brain, by Michael Paterniti. Nature Medicine, 6, 1090. Worth the read Brian Burrell (2005) Chapter 14: Einstein’s Brain NPR interview with Burrell http://www.npr.org/templates/story/story.php?storyId=4602913 The book includes an excellent critical review of the scientific studies performed with bits of the brain. Some background Mirian Diamond’s early studies on enriched environments Neurons & Glia Enriched environments increase the number of glia per neuron in rat cortex http://www.youtube.com/watch?v=JNOKT-xv7Dw&feature=related Diamond et al., 1985 “It was necessary to pool all glial cells counted to attain statistically significant differences” 4 brain regions X 7 total measures = 28 1)neurons, 2)astrocytes, 3)oligodendrocytes, 4)pooled glia 5) neuron:astro, 6)neuron:oligo, 7)neuron:pooled glia One out of 28 results were significant (p<.05 if you ignore previous tests): Einstein had a smaller neuron-to-glial cell ratio in area 39 of the left hemisphere. Concluded that, like rats exposed to an enriched environment, Einstein had more glial cells to support neurons in a brain region mediating visuospatial and math functions. Many flaws with the study: unspecified control, questionable data selection, transformation and statistical tests etc. Neuron size and number not different. Neuron density is greater (with thinner cortex) Area 9 in prefrontal cortex Same number of neurons packed in a thinner cortex, but why? A possible interpretation “…an increase in neuronal density might be advantageous by decreasing interneuronal conduction time…[which] has been posited as a limiting feature in the development of brain size and cortical connectivity.” Hmm, any other possibilities? Critical thinking a) Two main cell types neurons and glia b) Diamond et al. (1985) - Area 39 found more glia per neuron – greater support for neurons. c) Anderson and Harvey (1996) – Area 9 found greater neuronal density without any difference in neuron number or size. d) Greater density + thinner cortex, what might that tell you about glia cells? Critical thinking LESS GLIA PER NEURON!!! They ignore the possibility that a decrease in glial cells increased neuron density and thinned the cortex. Does that mean less support for neurons in area 9 of the prefrontal cortex??? Area 39 is also associated with language… Critical thinking With respect to Area 39: What are two ways to get a smaller neuron:glia ratio? 1) decrease neurons 2) increase glia Diamond et al. assumed the latter, but… Maybe the glial cells were increased because of early neuronal damage (or excessive pruning) related to Einstein’s delayed language development A picture is worth a million $ Figure 1 Photographs taken in 1995 of five views of Einstein’s whole brain (meninges removed) A, superior; B, left lateral; C, right lateral; D, inferior; E, midsagittal view of the left hemisphere. The arrow in each hemisphere indicates the posterior ascending branch of the Sylvian fissure as it runs into (is confluent with) the postcentral sulcus (compare with figure 2). Consequently, there is no parietal operculum in either hemisphere. Scale bar, 1 cm. Figure 2: Lateral photographs and tracings of left (solid line) and right (dashed line) superimposed hemispheres of a typical control male brain (1, 2, 3) and the brain of Einstein (4, 5, 6) The photographs of the control brain show the parietal operculum in the left (stippled) and right (hatched) hemisphere, situated between the postcentral (PC) sulcus and the posterior ascending branch of the Sylvian fissure (SF), which originates at the point of bifurcation () and terminates at S. PC1 is the inferior end of PC at SF. The tracing of the superimposed hemispheres (3) shows the asymmetry in position and size between the parietal opercula. The tracing of Einstein’s hemispheres (6) highlights the confluence of PC and the posterior ascending branch of SF in each hemisphere, the absence of the parietal opercula, and the symmetry of the sulcal morphology between hemispheres. Comparison of the tracings shows the relatively anterior position of the SF bifurcation in Einstein, and the associated greater posterior parietal expanse, particularly in his left hemisphere compared with the control brain. “An extraordinarily large expanse of highly integrated cortex within a functional network” Another look at the pics! Falk, D. (2009). New information about Albert Einstein’s brain. Frontiers in Evolutionary Neuroscience, 1, 1-6. Pictures of Einstein’s brain were compared to 58 control brains Results • Parietal lobes were larger • Rare pattern of groves and ridges • Pronounced knoblike structure in part of the motor cortex that controls the left hand (associated with musical ability) • Unusual primary somatosensory and motor cortices Conclusion “It is possible that these atypical aspects of Einstein’s cerebral cortex were related to the difficulty with which he acquired language, his preference for thinking in sensory impressions including visual images rather than words, and his early training on the violin” “A. Einstein's astrocytic processes showed larger sizes and higher numbers of…bulbous endings...of unknown significance and they have been described occurring in Alzheimer's disease. These observations are placed in the context of the general discussion regarding the proposal – by other authors – that structural, postmortem characteristics of the aged brain of Albert Einstein may serve as markers of his cognitive performance, a proposal to which the authors of this paper do not subscribe, and argue against.” Lessons Review research carefully, even studies published in peer reviewed journals. 1) is the rationale sound? 2) are the methods used appropriate? 3) is the interpretation justified? Healthy skepticism = good science Einstein's Brain is a 1994 documentary by Kevin Hull following Japanese professor Kenji Sugimoto in his search for Albert Einstein's brain. It is produced by BBC Films,and is currently not available in any commercial format, but is on YouTube! http://www.youtube.com/watch?v=y9ulxEGlw5w&feature=related Localization of function • Is still an open question • As consumers of science, you should be a discerning critic of research findings • neo-phrenology or something more • Brains and behavior are incredibly complex… The brain paradox Flex your mental might… It’s all in how you use it Biopsychology in the news • • • • • http://www.npr.org/ http://www.biopsychology.com/ http://www.brainconnection.com/ http://www.sfn.org/ http://www.dana.org/braincenter.cfm USE PRIMARY JOURNAL ARTICLES (NOT NEWS REPORTS) FOR YOUR ARTICLE SUMMARY. THESE REPORTS MAY HELP TRACK DOWN INTERESTING JOURNAL ARTICLES.