Making Sense of the Senses: ‘Context’ Matters When the Brain Interprets Sounds
The brain’s interpretation of sound is influenced by cues from other
senses, explaining more precisely how we interpret what we hear at a
particular moment, according to a report published online October 31 in Nature Neuroscience.
the new study in mice, researchers at NYU Langone Medical Center found
that nerve cells dedicated to hearing also rely on surrounding context
to properly interpret and react to familiar sounds.
brain ‘hears’ depends on what is ‘seen’ in addition to specific sounds,
as the brain calculates how to respond,” says study senior investigator
and neuroscientist Robert Froemke, PhD, an assistant professor at NYU Langone and its Skirball Institute of Biomolecular Medicine.
says his team’s latest findings reveal that while mammals recognize
sounds in the auditory cortex of their brains, the signaling levels of
nerve cells in this brain region are simultaneously being strengthened
or weakened in response to surrounding context.
“Our study shows
how the same sound can mean different things inside the brain depending
on the situation,” says Froemke. “We know, for instance, that people
learn to respond without alarm to the honk of a car horn if heard from
the safety of their homes, but are startled to hear the same honk while
crossing a busy street.”
If further experiments find similar
activity in human brains, the researchers say their work may lead to
precise explanations of situation-specific behaviors, such as anxiety brought on during math exams; sudden post-traumatic stress among combat veterans hearing a car backfire; and the ability of people with dementia to better remember certain events when they hear a familiar voice or see a friend’s face.
map how the same sense can be perceived differently in the brain, the
NYU Langone team, led by postdoctoral fellow Kishore Kuchibhotla, PhD,
monitored nerve circuit activity in mice when the animals expected, and
did not expect, to get a water reward through a straw-like tube (that
they see) after the ringing of a familiar musical note.
were exposed to specific auditory cues, researchers observed patterns
based on a basic divide in the nature of nerve cells. Each nerve cell
“decides” whether a message travels onward in a nerve pathway. Nerve
cells that emit chemicals which tell the next cell in line to amplify a
message are excitatory; those that stop messages are inhibitory.
Combinations of the two strike a counterbalance critical to the function
of the nervous system, with inhibitory cells sculpting “noise” from
excitatory cells into the arrangements behind thought and memory.
the processing of incoming sensory information is achieved in part by
adjusting signaling levels through each type of nerve cell. Theories
hold that the brain may attach more importance to a given signal by
turning up or down excitatory signals, or by doing the same with
inhibitory nerve cells.
In the current study, researchers found to
their surprise that most of the nerve cells in auditory cortex neurons
that stimulate brain activity (excitatory) had signaled less (had
“weaker” activity) when the mice expected and got a reward. Meanwhile,
and to the contrary, a second set of remaining “excitatory” neurons saw
greater signaling activity when mice expected a reward based on exposure
to the two sensory cues and got one.
Further tests showed that
the activation of specific inhibitory neurons—parvalbumin, somatostatin,
and vasoactive intestinal peptide—was responsible for these changes and
was in turn controlled by the chemical messenger, or neurotransmitter,
acetylcholine. Chemically shutting down acetylcholine activity cut in
half the number of times mice successfully went after their water reward
when prompted by a ring tone. Some studies in humans have linked
acetylcholine depletion to higher rates of Alzheimer’s disease.
who is also a faculty scholar at the Howard Hughes Medical Institute,
says the team next plans to assess how the hormones noradrenaline and
dopamine affect auditory cortex neurons under different situations.
we can sort out the many interactions between these chemicals and brain
activity based on sensory perception and context, then we can possibly
target specific excitatory and inhibitory neurological pathways to
rebalance and influence behaviors,” says Froemke.
What was the relationship between Sephardim and Ashkenazim on the West Coast?
By Leora Singer, Former Research Intern
This is my second blog
post in a series of three posts in which I discuss the theme of Sephardim in
the West Coast in the 19th-20th century. You can see my first post here. In this post, I compare and contrast
the relationship between Ashkenazim and Sephardim in Seattle and San Francisco.
When Calvo and Policar
(the first two Sephardim in Seattle) first encountered the Orthodox Ashkenazi
Jews living in the city, they weren’t exactly welcomed with open arms. These
observant Jews didn’t believe that Policar and Calvo were “real Jews” because
they spoke Greek instead of Yiddish (Adatto, 56), and their names didn’t “sound
Jewish” (Angel, 553). Because they felt ostracized by the Jewish community,
Calvo and Policar spent a lot of time with Greek non-Jews living in Seattle
(Adatto, 58). Fortunately, the rabbi of Bikur Holim, an Orthodox synagogue,
convinced the Orthodox Ashkenazim that the Sephardim were just as observant as
they were. The Ashkenazim accepted Calvo and Policar as members of the Jewish
The Seattle Sephardic
community kept growing as Calvo and Policar brought family members over, and
these family members spread the word about the opportunities available in
Seattle (Adatto, 60). In 1904, the first Rhodesli Sephardic immigrant came to
Seattle (FitzMorris, 29). As the number of Sephardim in Seattle grew, their
ties to the overall Jewish community of Seattle grew. Many Sephardim prayed at
Bikur Holim. They felt somewhat connected to the Orthodox Ashkenazim because
they, like the Sephardim, upheld high religious standards (Adatto, 116).
However, the perception was that their cultures were just too different to mix
together, so the Sephardim and Orthodox Ashkenazim remained fairly separate.
For example, intermarriage between the two groups was highly rare (Adatto,
Despite its rocky
nature, the beginning of the relationship between Orthodox Sephardim and
Orthodox Ashkenazim was still stronger than the beginning of the relationship
between Sephardim and Reform Ashkenazim. The Sephardim distrusted the Reform
Ashkenazim because they believed that the Reform Ashkenazim were not following
enough of the Jewish traditions. Fortunately, Aubrey Levy from the Reform
Temple de Hirsch helped to change this negative view of Reform Judaism by
forming a friendship with the Sephardic Jews. As a lawyer, he helped Sephardim
with legal work, free of charge. For example, in 1914, he assisted them with
the legal logistics in the purchase of the (previously Ashkenazi-owned) Bikur
Holim synagogue (Adatto, 118-119). Levy was highly regarded by the Sephardim.
By association, his synagogue became highly regarded as well. In fact, many
Sephardic children got their Jewish education at the Hebrew School of Temple de
Hirsch. However, even after many years, there was still very little
intermarriage. The Sephardim still did not feel like a part of Ashkenazi
There was a temporary
Sephardic congregation in the early 1850s (Zerin, 30). The congregation was
called Shaar Hashamayim. It was so temporary that it never even had a building
because the congregation stopped meeting only a few months after its creation
(Zerin, 47). This is likely because the construction of new buildings for two
Ashkenazi-run synagogues, Temple Emanu-El and Temple Sherith- Israel, was
underway. Since the Sephardim and Ashkenazim in San Francisco were united,
(especially in comparison to these sects in other West Coast cities) the
Sephardim didn’t want to divide it by having their own synagogue. Also, some
members of the Sephardic congregation had been leaders in the other synagogues,
because they were so prominent and respected by the Ashkenazim (Stern and
Sephardim from San
Francisco are sometimes difficult to identify because intermarriage with
Ashkenazim and even non-Jews was common (Stern and Kramer, 45). This practice
showed a stark difference between the Jews of San Francisco and in other West
Coast cities. In the other cities, intermarriage between pretty much anyone
that was not a Jew from your home country was frowned upon.
Adatto, Albert. Sephardim
and the Seattle Sephardic Community. Seattle: U of Washington, 1939. Print.
Angel, Marc D., Hasson,
Aron, Kramer, William M., Maimon, Isaac, Samuels, Beth, Sidell, Loraine, Stern,
Norton B. Sephardic Jews in the West Coast States : An Anthology. 1st
ed. Los Angeles: Published for the Skirball Cultural Center, Los Angeles by the
Western States Jewish History Association, 1996. Print. Western States Jewish
History ; v. 28, No. 1-3.
Stern, Stephen. The
Sephardic Jewish Community of Los Angeles. New York: Arno, 1980. Print.
Folklore of the World (New York).
Edward. Jewish San Francisco. Charleston, SC: Arcadia, 2006. Print.
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