Navigation Links
Stuck in neutral: Brain defect traps schizophrenics in twilight zone

People with schizophrenia struggle to turn goals into actions because brain structures governing desire and emotion are less active and fail to pass goal-directed messages to cortical regions affecting human decision-making, new research reveals.

Published in Biological Psychiatry, the finding by a University of Sydney research team is the first to illustrate the inability to initiate goal-directed behaviour common in people with schizophrenia.

The finding may explain why people with schizophrenia have difficulty achieving real-world goals such as making friends, completing education and finding employment.

"The apparent lack of motivation in schizophrenic patients isn't because they lack goals or don't enjoy rewards and pleasure," says the University of Sydney's Dr Richard Morris, the study's lead author. "They enjoy as many experiences as other people, including food, movies and scenes of natural beauty.

"What appears to block them are specific brain deficits that prevent them from converting their desires and goals into choices and behaviour."

Using a control group research design, the researchers used a two-prong approach to reveal how and why schizophrenics fail to convert their preferences into congruent choices.

First, using a series of experiments involving choosing between different snack food rewards, experimenters revealed that:

  • schizophrenic subjects had a liking for snack foods equivalent to healthy adults
  • when researchers reduced the value of one of the snacks, both subjects and healthy adults subsequently preferred different snacks, as expected
  • surprisingly, schizophrenic subjects had major difficulty choosing their preferred snack when provided with a choice between their preferred snack and the devalued snack.

Second, researchers used functional magnetic resonance imaging (fMRI) to measures brain activity while study subjects performed learning tasks involving snack foods. This technique relies on the fact that cerebral blood flow and neuronal activity are coupled.

When an area of the brain is in use, bloodflow to that region increases, thereby indicating neural activity. This neural activity can be presented graphically by colour-coding the strength of activation across the brain or in specific brain regions. The technique can localise neural activity to within millimetres.

Functional MRI results revealed the following:

  • schizophrenic subjects had normal neural activity in the brain region responsible for decision-making (prefrontal cortex)
  • among schizophrenic subjects, brain regions responsible, in part, for controlling actions and choice (the caudate) had far lower neural activity than in healthy subjects
  • lower neural activity in the caudate regions was correlated with the difficulty that schizophrenic subjects' had applying their food preferences to obtain future snack foods.

"Pathology in the caudate and associated brain regions may prevent schizophrenic subjects from properly evaluating their desires then transmitting that information to guide their behavior," says Dr Morris.

"This means that desires and goals are intact in people with schizophrenia, however they have difficulty choosing the right course of action to achieve those goals.

"This failure to integrate desire with action means people with schizophrenia are stuck in limbo, wanting a normal life but unable to take the necessary steps to achieve it."

Schizophrenia affects one per cent of people worldwide, including in Australia. However so-called "poor motivation" in schizophrenia is a major economic concern because it is not treated by current medicines, and often means patients fail to finish their education or hold a full-time job.


Contact: Dan Gaffney
University of Sydney

Related medicine news :

1. Those with episodic amnesia are not stuck in time, says philosopher Carl Craver
2. US Drug Watchdog Now Urges All Metal on Metal Hip Implant Failure Victims To Get A New Opinion From Another Orthopedic Surgeon Before They Get Stuck With a New Problem
3. US Drug Watchdog Now Urges All Women Stuck with a Failed Transvaginal Mesh Product Failure to Call Them for Names of National Caliber Attorneys
4. Stuck in the throat
5. Chinese Drywall Complaint Center Now Demands Leadership From Obama & EPA, For Homeowners In Florida And In The US Southeast Stuck In Toxic Chinese Drywall Hell-Forward?
6. Dr. Patrick Walsh, Director of the Marianjoy Psychology Department Appointed to the State of Illinois Brain and Spinal Cord Injury Advisory Council
7. Bats bolster brain hypothesis, maybe technology, too
8. New non-invasive technique controls size of molecules penetrating the blood-brain barrier
9. Researchers Pinpoint Brain Region Where Contextual Memories Are Made
10. Decline in daily functioning related to decreased brain activity in Alzheimers
11. Researchers Create Functional 3-D Brain-Like Tissue
Post Your Comments:
(Date:10/13/2017)... ... 13, 2017 , ... Coveros, a leader in agile coaching ... contract by the Center for Medicare and Medicaid Services (CMS). The Enterprise Agile ... of Agile methodologies in a consistent and high value manner across CMS programs. ...
(Date:10/13/2017)... ... October 13, 2017 , ... “America On The Brink”: ... “America On The Brink” is the creation of published author, William Nowers. ... As a WWII veteran, he spent thirty years in the Navy. Following ...
(Date:10/12/2017)... Francisco, CA (PRWEB) , ... October 12, 2017 ... ... Dr. Cheng, are now treating sleep apnea using cutting-edge Oventus O2Vent ... apnea, a serious sleep disorder characterized by frequent cessation in breathing. Oral appliances ...
(Date:10/12/2017)... (PRWEB) , ... October 12, 2017 , ... ... products to meet the demand of today’s consumer and regulatory authorities worldwide. From ... probiotic experts and tested to meet the highest standard. , These products ...
(Date:10/12/2017)... ... October 12, 2017 , ... The American College of ... Carol Friedman, PhD, FACMI, during the Opening Session of AMIA’s Annual Symposium in Washington, ... In honor of Morris F. Collen, a pioneer in the field of medical informatics, ...
Breaking Medicine News(10 mins):
(Date:10/12/2017)... 2017 West Pharmaceutical Services, Inc. ... injectable drug administration, today announced that it will release ... Thursday, October 26, 2017, and will follow with a ... at 9:00 a.m. Eastern Time. To participate on the ... conference ID is 94093362. ...
(Date:10/10/2017)... , Oct. 10, 2017  NDS received FDA 510(k) clearance ... a medical-grade battery-powered display stand specifically designed for endoscopy environments. An ... technology into a clinical solution to support the improvement of patient ... Innovative Design ... Wireless Solution ...
(Date:10/4/2017)... Oct. 4, 2017  According to the Centers for Disease Control and ... October . PhysicianOne Urgent Care is helping communities across Massachusetts ... , by offering no-cost* flu shots through the end of the ... certain health insurance regulations. ... time to get a flu shot is by the end of October, ...
Breaking Medicine Technology: