Friday, June 26, 2015

There May Not Be a Single Language Comprehension Center in the Brain

A recent paper in the journal Brain, a journal of neurology, challenges the long-held notion that the sensory speech area of the left temporal lobe of the cerebrum—often called the Wernicke area—acts as the center of language comprehension.

Wernicke area
The report describes research that leads one to the conclusion that although the Wernicke area (pictured) apparently has a role in understanding individual words, the task of sentence comprehension is accomplished by a complex network of diverse areas of the cerebrum. These include, "temporoparietal components of Wernicke’s area, Broca’s area, and [the] dorsal premotor cortex."

What can we use from this in teaching undergraduate A&P?

  • When discussing the sensory speech (Wernicke) area, one might bring up this discovery and how it may modify our description of its main function.

  • This discovery is a good example of how science works—how theories are formed and how they are modified as new information is discovered.  And how new research must be confirmed before it becomes widely established as fact.

  • When discussing cerebral localization of function, this story may be helpful in emphasizing that complex cerebral functions often involve integration of diverse cortical areas.

  • This story is a good example of our rapidly advancing knowledge of complex brain function.

  • You'll sound very "with it" when you can drop in casual asides about the latest brain research in your classroom discussions!

Want to know more?

New Human Brain Language Map | Researchers find that Wernicke’s area, thought to be the seat of language comprehension in the human brain for more than a century, is not.
  • Bob Grant. The Scientist  Published online June 26, 2015
  • Brief, plain-English article summarizing the recent findings.

The Wernicke conundrum and the anatomy of language comprehension in primary progressive aphasia 
  • M-Marsel Mesulam , et al. Brain. DOI: First published online: 25 June 2015
  • The original research article.

Scientists redraw traditional brain map of language comprehension
  • Northwestern University press release. Published online June 25, 2015

Cortical Areas Involved in Speech Processing

Image credits: Database Center for Life Science (Wernicke area)
Leuthardt, et al. (cortical speech areas)

Monday, June 15, 2015

Virtual Cardiology Lab

Looking for a supplemental hands-on activity with cardiology in your course?

Try the FREE online interactive Cardiology Virtual Lab from the Howard Hughes Medical Institute.

It covers these concepts:
  • Symptoms of a selection of heart diseases, to serve as examples of what kinds of things can go wrong with the heart. 
    • How are symptoms detected and why?
  • Tools and techniques used for diagnosis. 
    • What can the different techniques detect and how do they work?
  • Principles of pedigree analysis.

What can we use from this in teaching undergraduate A&P?

  • Link to this virtual lab activity from your online syllabus, course web page, or LMS (or in an email  or tweet to students)
  • If you want to give course points for the lab, consider an online quiz or lab report submitted through your learning management system (LMS) or emailed to you.
  • Gives students a "real life" clinical lab application for the concepts they are learning in A&P.
  • Provides a cardiology lab option for online/hybrid courses or wet labs that don't have funding for cardiology experiments.
  • Helps integrate principles of genetics with cardiology, so it can be used in your genetics unit.

Want to know more?

Cardiology Virtual Lab

  • BioInteractive. Howard Hughes Medical Institute. Accessed 16 Sep 2014.
  • This virtual lab will familiarize you with heritable diseases of the heart. Learn about the diagnostic tools used to examine and diagnose patients.

BioInteractive Virtual Labs

  • BioInteractive. Howard Hughes Medical Institute. Accessed 16 Sep 2014.
  • List of all the FREE virtual labs offered by HHMI's BioInteractive project.

Cardiovascular Topics

  • Kevin Patton. The A&P Professor. Various dates.
  • List of previous blog posts on cardiovascular topics

Wednesday, June 3, 2015

A Brain-Lymphatic Connection

Existing dogma in neuroscience states that the brain does not possess the classical lymphatic drainage system found in other parts of body. However, a recent letter in the journal Nature reports the discovery of lymphatic vessels lining the dural sinuses in mice. These were shown to drain immune cells and cerebrospinal fluid (CSF) into the deep cervical lymph nodes.

Although more work is yet to be done in humans, this discovery will cause neuroscientists to revisit a number of concepts related to CSF and lymphatic drainage, as well as immune functions in the brain.

For example, do these new data truly challenge the notion of immune privilege in the nervous tissue of the central nervous system—or do they apply to the brain as an organ and allow for lymphatic drainage of tissues outside the nervous tissue of the brain?

What can we use from this in teaching undergraduate A&P?

  • When discussing CSF drainage, consider mentioning the possibility that filtration of CSF directly into dural sinuses may be augmented by the newly discovered lymphatic drainage.

  • If you discuss the dogma of the "immune privilege" of the brain, consider mentioning this possible challenge to the concept. This may trigger a great discussion of whether these newly discovered lymphatic vessels are truly "in the brain."

  • If you discuss disorders involving altered immunity, such as multiple sclerosis, consider mentioning this discovery.

  • Bringing up this new information may be useful in discussions related to the process of science—how existing concepts are sometimes challenged by new information, for example. Perhaps a discussion of the need for more investigation would stimulate students to think about what future steps can be taken to map out a possible lymphatic network in or around the brain.
Current concept of lymphatic drainage (left) compared to updated version to reflect new data (right).

Want to know more?

Brain Drain | The brain contains lymphatic vessels similar to those found elsewhere in the body, a mouse study shows.
  • Ashley P. Taylor, The Scientist, June 1, 2015 (online)
  • Plain-English article summarizing the study and its significance.
Structural and functional features of central nervous system lymphatic vessels,
  • A. Louveau et al., Nature, June 1, 2015.doi:10.1038/nature14432, 
  • The original research article. Includes images and video.
Missing link found between brain, immune system; major disease implications
  • University of Virginia Health System, Science Daily, June 1, 2015
  • Illustrated press release describing the research.

Images: DBCLS (top)
Univ Va Health System (bottom)