Breaking News
March 22, 2019 - TMJ disorders could be treated with tissue-engineered implants after successful animal study
March 22, 2019 - Team-based approach is key to successful care of pregnant women with heart failure
March 22, 2019 - Study identifies gene variant associated with accelerated cellular aging
March 21, 2019 - Salk scientists show how background noise from neurons can interrupt focused attention
March 21, 2019 - New class of drugs could help treat patients diagnosed with ovarian cancer
March 21, 2019 - Tecentriq Approved for Small Cell Lung Cancer
March 21, 2019 - Adipocyte glucocorticoid receptors play a role in developing steroid diabetes
March 21, 2019 - Climate change can affect nutrient content of crops, harming human health
March 21, 2019 - Podcast: KHN’s ‘What The Health’ Surprise! Fixing Surprise Medical Bills Is Harder Than it Looks
March 21, 2019 - Chemistry researchers patent new method for making anti-leukemia compounds
March 21, 2019 - UIC scientists identify hidden proteins in bacteria
March 21, 2019 - New Australian drug trial achieves remarkable results in patients with acute myeloid leukemia
March 21, 2019 - Females live longer when they have help raising offspring
March 21, 2019 - How did orthodontists sell orthodontics?
March 21, 2019 - In the Spotlight: From dietitian to physician assistant student
March 21, 2019 - The CRISPR Revolution: What You Need to Know
March 21, 2019 - FDA Chief Calls For Stricter Scrutiny Of Electronic Health Records
March 21, 2019 - Combined glucocorticoid and antioxidant therapy could benefit premature babies
March 21, 2019 - Low levels of certain eye proteins could serve as predictor for Alzheimer’s
March 21, 2019 - Post-traumatic holocaust survivors transmit negative views on aging to offspring
March 21, 2019 - City of Hope receives $7.5 million in grant awards to study cutaneous T cell lymphoma
March 21, 2019 - New video game-led training device helps stroke survivors regain arm mobility
March 21, 2019 - Compounds in coffee could slow prostate cancer growth
March 21, 2019 - New mobile DNA element in Wolbachia may contribute to improved disease control strategies
March 21, 2019 - Phase 2 Clinical Trial of Bermekimab Shows Potential New Standard of Care for Treatment of Hidradenitis Suppurativa, Including Significant Pain Reduction without Antibiotics
March 21, 2019 - More than one-third of patients risk major bleeding by doubling up on blood thinners
March 21, 2019 - A skeptical look at popular diets: Thumbs up for Mediterranean
March 21, 2019 - PTSD After Cardiac Arrest Predicts More Heart Trouble
March 21, 2019 - Role of immunological imprinting in elicitation of new antibodies
March 21, 2019 - Breast cancer relapse predictor tool may soon be a reality
March 21, 2019 - New computer program developed by TGen lights up cancer-causing genetic mutations
March 21, 2019 - FDA warns two breast implant makers for failure to comply with post-approval study requirements
March 21, 2019 - Butler Hospital receives COBRE grant to enhance research on neuropsychiatric illnesses
March 21, 2019 - Majority of osteoporosis clinical practice guidelines ignore patients’ voices
March 21, 2019 - Generic messages don’t help patients to lose weight
March 21, 2019 - Eisai and Imbrium Therapeutics Announce U.S. FDA Filing Acceptance of New Drug Application for Lemborexant for the Treatment of Insomnia
March 21, 2019 - Two-drug combos using popular calcium channel blocker show superiority in lowering BP
March 21, 2019 - First-in-human pilot study shows positive results for ‘bacteria-phobic’ catheter
March 21, 2019 - Itamar Medical launches next-generation WatchPAT system for home sleep apnea testing
March 21, 2019 - Study estimates health and economic impacts of healthy food prescriptions
March 21, 2019 - Detecting fungal disease in crops with multispectral imaging system
March 21, 2019 - MIT announces creation of the Alana Down Syndrome Center
March 21, 2019 - Next-generation LVAD device clinically superior, safer for heart failure patients
March 21, 2019 - Allergan Announces FDA Approval of Avycaz (ceftazidime and avibactam) for Pediatric Patients
March 21, 2019 - Mutations in noncoding genes could play big role in regulating cancer, study finds
March 21, 2019 - A medical student’s thoughts on Match Day
March 21, 2019 - Are eggs good or bad for you?
March 21, 2019 - New analysis reveals precision oncology insights for colorectal cancer
March 21, 2019 - Pollutants appear to weaken immune system and increase pathogen virulence
March 21, 2019 - Researchers develop and validate scale for rating severity of mononucleosis
March 21, 2019 - Scientists identify generation of key immune response in mice on introducing solid food
March 21, 2019 - New nanomaterial could restore internal structure of damaged bones
March 21, 2019 - Selective destruction of prostate tumor as effective as complete prostate removal
March 21, 2019 - 2011 to 2015 Saw Increase in Psychiatric ED Visits for Youth
March 21, 2019 - Tapeworm drug targets common vulnerability in tumor cells
March 21, 2019 - WVU researcher discovers higher suicide rate among Medicaid-insured youth
March 21, 2019 - Off the beaten path for global health residency
March 21, 2019 - European Parliament’s report calls on EU to develop policies to regulate endocrine-disrupting chemicals
March 21, 2019 - Women with undiagnosed diabetes in pregnancy more likely to experience stillbirths
March 21, 2019 - Fish consumption can help prevent asthma, study reveals
March 21, 2019 - Royal Holloway professors to lead new to research into curing Neurofibromatosis type 1
March 21, 2019 - NSF offers grant to improve treatment approaches for pelvic organ prolapse
March 21, 2019 - Your Apple Watch Might Help Spot a Dangerous Irregular Heartbeat
March 21, 2019 - Research team uncovers critical new clues about what goes awry in autistic brains
March 21, 2019 - From March Madness to medicine with help from mentors
March 21, 2019 - Mental health disorders among young adults may be on the increase
March 21, 2019 - New study examines smarter automatic defibrillator
March 21, 2019 - UC Riverside research shows how natural selection favors cheaters
March 21, 2019 - Mother’s diet during pregnancy can impact lung-specific genes of her offspring
March 21, 2019 - AeroForm Tissue Expanders makes breast reconstruction after mastectomy more comfortable
March 21, 2019 - New project focuses on creating more responsive, intuitive prosthetics
March 21, 2019 - New case study describes adolescent patient with rapid-onset schizophrenia and Bartonella infection
March 21, 2019 - Umass Amherst food scientist honored with 2019 Young Scientist Research Award
March 21, 2019 - Smell of skin could lead to early diagnosis for Parkinson’s
March 21, 2019 - Difference in brain connectivity may explain autism spectrum disorder
March 21, 2019 - Untangling the microbiome — with statistics
March 21, 2019 - Human microbiome metabolites enhance colon injury by enterohemorrhagic E. coli, study shows
March 21, 2019 - Written media can improve citizens’ understanding of palliative care
March 21, 2019 - New research aims to find how asthma symptoms are aggravated
March 21, 2019 - New $9.7 million NIH grant project seeks to improve hearing restoration
How does our brain perceives the environment?

How does our brain perceives the environment?

image_pdfDownload PDFimage_print

Nearly 30 years ago, scientists demonstrated that visually recognizing an object, such as a cup, and performing a visually guided action, such as picking the cup up, involved distinct neural processes, located in different areas of the brain. A new study shows that the same is true for how the brain perceives our environment — it has two distinct systems, one for recognizing a place and another for navigating through it.

The Journal of Neuroscience published the finding by researchers at Emory University, based on experiments using functional magnetic resonance imaging (fMRI). The results showed that the brain’s parahippocampal place area responded more strongly to a scene recognition task while the occipital place area responded more to a navigation task.

The work could have important implications for helping people to recover from brain injuries and for the design of computer vision systems, such as self-driving cars.

“It’s thrilling to learn what different regions of the brain are doing,” says Daniel Dilks, senior author of the study and an assistant professor of psychology at Emory. “Learning how the mind makes sense of all the information that we’re bombarded with every day is one of the greatest of intellectual quests. It’s about understanding what makes us human.”

Entering a place and recognizing where you are — whether it’s a kitchen, a bedroom or a garden — occurs instantaneously and you can almost simultaneously make your way around it.

“People assumed that these two brain functions were jumbled up together — that recognizing a place was always navigationally relevant,” says first author Andrew Persichetti, who worked on the study as an Emory graduate student. “We showed that’s not true, that our brain has dedicated and dissociable systems for each of these tasks. It’s remarkable that the closer we look at the brain the more specialized systems we find — our brains have evolved to be super efficient.”

Persichetti, who has since received his PhD from Emory and now works at the National Institute of Mental Health, explains that an interest in philosophy led him to neuroscience. “Immanuel Kant made it clear that if we can’t understand the structure of our mind, the structure of knowledge, we’re not going to fully understand ourselves, or even a lot about the outside world, because that gets filtered through our perceptual and cognitive processes,” he says.

The Dilks lab focuses on mapping how the visual cortex is functionally organized. “We are visual creatures and the majority of the brain is related to processing visual information, one way or another,” Dilks says.

Researchers have wondered since the late 1800s why people suffering from brain damage sometimes experience strange visual consequences. For example, someone might have normal visual function in all ways except for the ability to recognize faces.

It was not until 1992, however, that David Milner and Melvyn Goodale came out with an influential paper delineating two distinct visual systems in the brain. The ventral stream, or the temporal lobe, is involved in object recognition and the dorsal stream, or the parietal lobe, guides an action related to the object.

In 1997, MIT’s Nancy Kanwisher and colleagues demonstrated that a region of the brain is specialized in face perception — the fusiform face area, or FFA. Just a year later, Kanwisher’s lab delineated a neural region specialized in processing places, the parahippocampal place area (PPA), located in the ventral stream.

While working as a post-doctoral fellow in the Kanwisher lab, Dilks led the finding of a second region of the brain specialized in processing places, the occipital place area, or OPA, located in the temporal stream.

Dilks set up his own lab at Emory the same year that discovery was published, in 2013. Among the first questions he wanted to tackle was why the brain had two regions dedicated to processing places.

Persichetti designed an experiment to test the hypothesis that place processing was divided in the brain in a manner similar to object processing. Using software from the SIMS life simulation game, he created three digital images of places: A bedroom, a kitchen and a living room. Each room had a path leading through it and out one of three doors.

Study participants in the fMRI scanner were asked to fixate their gaze on a tiny white cross. On each trial, an image of one of the rooms then appeared, centered behind the cross. Participants were asked to imagine they were standing in the room and indicate through a button press whether it was a bedroom, a kitchen or a living room. On separate trials, the same participants were also asked to imagine that they were walking on the continuous path through the exact same room and indicate whether they could leave through the door on the left, in the center, or on the right.

The resulting data showed that the two brain regions were selectively activated depending on the task: The PPA responded more strongly to the recognition task while the OPA responded more strongly to the navigation task.

“While it’s incredible that we can show that different parts of the cortex are responsible for different functions, it’s only the tip of the iceberg,” Dilks says. “Now that we understand what these areas of the brain are doing we want to know precisely how they’re doing it and why they’re organized this way.”

Dilks plans to run causal tests on the two scene-processing areas. Repetitive transcranial magnetic stimulation, or rTMS, is a non-invasive technology that can be attached to the scalp to temporarily deactivate the OPA in health participants and test whether someone can navigate without it.

The same technology cannot be used to deactivate the PPA, due to its deeper location in the temporal lobe. The Dilks lab plans to recruit participants suffering brain injury to the PPA region to test for any effects on their ability to recognize scenes.

Clinical applications for the research include more precise guidance for surgeons who operate on the brain and better brain rehabilitation methods.

“My ultimate goal is to reverse-engineer the human brain’s visual processes and replicate it in a computer vision system,” Dilks says. “In addition to improving robotic systems, a computer model could help us to more fully understand the human mind and brain.”

Source:

https://search.emory.edu/

Tagged with:

About author

Related Articles