Luminance: a state or quality of radiating or reflecting light

 

candidscience:

CAN YOU HEAR ME??

Hearing is an amazing sense that we often take for granted.  Think how intricately all the parts work together to convey sound to the brain: The external ear acts as a funnel to collect sound waves.  The waves travel down the ear canal where they will contact the ear drum and make it vibrate. The movement is then passed to the middle ear OSSICLES which are joined to each other and the ear drum.  The motion of the ossicles serves to amplify the sound and pass the motion along to the inner ear COCHLEA.  Sound waves enter the cochlea by motion of the stapes and cause waves in the fluid of the inner ear.  The waves move the tiny cochlear cells, called HAIR CELLS because of the ‘tuft’ of cilia at the tops of each cell.  The movement of the cells depends on the pitch and volume of the incoming sound.  As the cells move, they pass an electrical charge to the auditory nerve and into the portion of the brain responsible for hearing.

Watch how the hair cells will actually respond to Rock Around the Clock! (http://youtu.be/Xo9bwQuYrRo)

Images:

External Ear; external ear graphic

Middle Ear Ossicles; middle ear diagram

Cochlea; parts of the ear diagram

Hair cell in the cochlea; hair cell diagram

neurosciencestuff:

Study finds stem cell combination therapy improves traumatic brain injury outcomes
Traumatic brain injuries (TBI), sustained by close to 2 million Americans annually, including military personnel, are debilitating and devastating for patients and their families. Regardless of severity, those with TBI can suffer a range of motor, behavioral, intellectual and cognitive disabilities over the short or long term. Sadly, clinical treatments for TBI are few and largely ineffective.
In an effort to find an effective therapy, neuroscientists at the Center of Excellence for Aging and Brain Repair, Department of Neurosurgery in the USF Health Morsani College of Medicine, University of South Florida, have conducted several preclinical studies aimed at finding combination therapies to improve TBI outcomes.
In their study of several different therapies—alone and in combination—applied to laboratory rats modeled with TBI, USF researchers found that a combination of human umbilical cord blood cells (hUBCs) and granulocyte colony stimulating factor (G-CSF), a growth factor, was more therapeutic than either administered alone, or each with saline, or saline alone.
The study appeared in a recent issue of PLoS ONE.
“Chronic TBI is typically associated with major secondary molecular injuries, including chronic neuroinflammation, which not only contribute to the death of neuronal cells in the central nervous system, but also impede any natural repair mechanism,” said study lead author Cesar V. Borlongan, PhD, professor of neurosurgery and director of USF’s Center of Excellence for Aging and Brain Repair. “In our study, we used hUBCs and G-CSF alone and in combination. In previous studies, hUBCs have been shown to suppress inflammation, and G-CSF is currently being investigated as a potential therapeutic agent for patients with stroke or Alzheimer’s disease.”
Their stand-alone effects have a therapeutic potential for TBI, based on results from previous studies. For example, G-CSF has shown an ability to mobilize stem cells from bone marrow and then infiltrate injured tissues, promoting self-repair of neural cells, while hUBCs have been shown to suppress inflammation and promote cell growth.
The involvement of the immune system in the central nervous system to either stimulate repair or enhance molecular damage has been recognized as key to the progression of many neurological disorders, including TBI, as well as in neurodegenerative diseases such as Parkinson’s disease, multiple sclerosis and some autoimmune diseases, the researchers report. Increased expression of MHCII positive cells—cell members that secrete a family of molecules mediating interactions between the immune system’s white blood cells—has been directly linked to neurodegeneration and cognitive decline in TBI.
“Our results showed that the combined therapy of hUBCs and G-CSF significantly reduced the TBI-induced loss of neuronal cells in the hippocampus,” said Borlongan. “Therapy with hUBCs and G-CSF alone or in combination produced beneficial results in animals with experimental TBI. G-CSF alone produced only short-lived benefits, while hUBCs alone afforded more robust and stable improvements. However, their combination offered the best motor improvement in the laboratory animals.”
“This outcome may indicate that the stem cells had more widespread biological action than the drug therapy,” said Paul R. Sanberg, distinguished professor at USF and principal investigator of the Department of Defense funded project. “Regardless, their combination had an apparent synergistic effect and resulted in the most effective amelioration of TBI-induced behavioral deficits.”
The researchers concluded that additional studies of this combination therapy are warranted in order to better understand their modes of action. While this research focused on motor improvements, they suggested that future combination therapy research should also include analysis of cognitive improvement in the laboratory animals modeled with TBI.

neurosciencestuff:

Study finds stem cell combination therapy improves traumatic brain injury outcomes

Traumatic brain injuries (TBI), sustained by close to 2 million Americans annually, including military personnel, are debilitating and devastating for patients and their families. Regardless of severity, those with TBI can suffer a range of motor, behavioral, intellectual and cognitive disabilities over the short or long term. Sadly, clinical treatments for TBI are few and largely ineffective.

In an effort to find an effective therapy, neuroscientists at the Center of Excellence for Aging and Brain Repair, Department of Neurosurgery in the USF Health Morsani College of Medicine, University of South Florida, have conducted several preclinical studies aimed at finding combination therapies to improve TBI outcomes.

In their study of several different therapies—alone and in combination—applied to laboratory rats modeled with TBI, USF researchers found that a combination of human umbilical cord blood cells (hUBCs) and granulocyte colony stimulating factor (G-CSF), a growth factor, was more therapeutic than either administered alone, or each with saline, or saline alone.

The study appeared in a recent issue of PLoS ONE.

“Chronic TBI is typically associated with major secondary molecular injuries, including chronic neuroinflammation, which not only contribute to the death of neuronal cells in the central nervous system, but also impede any natural repair mechanism,” said study lead author Cesar V. Borlongan, PhD, professor of neurosurgery and director of USF’s Center of Excellence for Aging and Brain Repair. “In our study, we used hUBCs and G-CSF alone and in combination. In previous studies, hUBCs have been shown to suppress inflammation, and G-CSF is currently being investigated as a potential therapeutic agent for patients with stroke or Alzheimer’s disease.”

Their stand-alone effects have a therapeutic potential for TBI, based on results from previous studies. For example, G-CSF has shown an ability to mobilize stem cells from bone marrow and then infiltrate injured tissues, promoting self-repair of neural cells, while hUBCs have been shown to suppress inflammation and promote cell growth.

The involvement of the immune system in the central nervous system to either stimulate repair or enhance molecular damage has been recognized as key to the progression of many neurological disorders, including TBI, as well as in neurodegenerative diseases such as Parkinson’s disease, multiple sclerosis and some autoimmune diseases, the researchers report. Increased expression of MHCII positive cells—cell members that secrete a family of molecules mediating interactions between the immune system’s white blood cells—has been directly linked to neurodegeneration and cognitive decline in TBI.

“Our results showed that the combined therapy of hUBCs and G-CSF significantly reduced the TBI-induced loss of neuronal cells in the hippocampus,” said Borlongan. “Therapy with hUBCs and G-CSF alone or in combination produced beneficial results in animals with experimental TBI. G-CSF alone produced only short-lived benefits, while hUBCs alone afforded more robust and stable improvements. However, their combination offered the best motor improvement in the laboratory animals.”

“This outcome may indicate that the stem cells had more widespread biological action than the drug therapy,” said Paul R. Sanberg, distinguished professor at USF and principal investigator of the Department of Defense funded project. “Regardless, their combination had an apparent synergistic effect and resulted in the most effective amelioration of TBI-induced behavioral deficits.”

The researchers concluded that additional studies of this combination therapy are warranted in order to better understand their modes of action. While this research focused on motor improvements, they suggested that future combination therapy research should also include analysis of cognitive improvement in the laboratory animals modeled with TBI.

neurosciencestuff:

What happened when? How the brain stores memories by time
Before I left the house this morning, I let the cat out and started the dishwasher. Or was that yesterday? Very often, our memories must distinguish not just what happened and where, but when an event occurred — and what came before and after. New research from the University of California, Davis, Center for Neuroscience shows that a part of the brain called the hippocampus stores memories by their “temporal context” — what happened before, and what came after.
"We need to remember not just what happened, but when," said graduate student Liang-Tien (Frank) Hsieh, first author on the paper published March 5 in the journal Neuron.
The hippocampus is thought to be involved in forming memories. But it’s not clear whether the hippocampus stores representations of specific objects, or if it represents them in context.
Hsieh and Charan Ranganath, professor in the Department of Psychology and the Center for Neuroscience, looked for hippocampus activity linked to particular memories. First, they showed volunteers a series of pictures of animals and objects. Then they scanned the volunteers’ brains as they showed them the same series again, with questions such as, “is this alive?” or “does this generate heat?”
The questions prompted the volunteers to search their memories for information. When the images were shown in the same sequence as before, the volunteers could anticipate the next image, making for a faster response.
From brain scans of the hippocampus as the volunteers were answering questions, Hsieh and Ranganath could identify patterns of activity specific to each image. But when they showed the volunteers the same images in a different sequence, they got different patterns of activity.
In other words, the coding of the memory in the hippocampus was dependent on its context, not just on content.
"It turns out that when you take the image out of sequence, the pattern disappears," Ranganath said. "For the hippocampus, context is critical, not content, and it’s fairly unique in how it pulls things together."
Other parts of the brain store memories of objects that are independent of their context, Ranganath noted.
"For patients with memory problems this is a big deal," Ranganath said. "It’s not just something that’s useful in understanding healthy memory, but allows us to understand and intervene in memory problems."

neurosciencestuff:

What happened when? How the brain stores memories by time

Before I left the house this morning, I let the cat out and started the dishwasher. Or was that yesterday? Very often, our memories must distinguish not just what happened and where, but when an event occurred — and what came before and after. New research from the University of California, Davis, Center for Neuroscience shows that a part of the brain called the hippocampus stores memories by their “temporal context” — what happened before, and what came after.

"We need to remember not just what happened, but when," said graduate student Liang-Tien (Frank) Hsieh, first author on the paper published March 5 in the journal Neuron.

The hippocampus is thought to be involved in forming memories. But it’s not clear whether the hippocampus stores representations of specific objects, or if it represents them in context.

Hsieh and Charan Ranganath, professor in the Department of Psychology and the Center for Neuroscience, looked for hippocampus activity linked to particular memories. First, they showed volunteers a series of pictures of animals and objects. Then they scanned the volunteers’ brains as they showed them the same series again, with questions such as, “is this alive?” or “does this generate heat?”

The questions prompted the volunteers to search their memories for information. When the images were shown in the same sequence as before, the volunteers could anticipate the next image, making for a faster response.

From brain scans of the hippocampus as the volunteers were answering questions, Hsieh and Ranganath could identify patterns of activity specific to each image. But when they showed the volunteers the same images in a different sequence, they got different patterns of activity.

In other words, the coding of the memory in the hippocampus was dependent on its context, not just on content.

"It turns out that when you take the image out of sequence, the pattern disappears," Ranganath said. "For the hippocampus, context is critical, not content, and it’s fairly unique in how it pulls things together."

Other parts of the brain store memories of objects that are independent of their context, Ranganath noted.

"For patients with memory problems this is a big deal," Ranganath said. "It’s not just something that’s useful in understanding healthy memory, but allows us to understand and intervene in memory problems."

Most people do not listen with the intent to understand; they listen with the intent to reply.

Stephen R. Covey (via riseabovethemadness)

(Source: onlinecounsellingcollege)

One day, whether you
are 14,
28 
or 65

you will stumble upon
someone who will start
a fire in you that cannot die.

However, the saddest,
most awful truth
you will ever come to find––

is they are not always
with whom we spend our lives.

Beau Taplin, "The Awful Truth" {Hunting Season – 28 copies left} (via to-passingthrough)

(Source: afadthatlastsforever)