BIOLOGICAL APPROACH Flashcards
ADAPTIVE TRAITS- ASSUMPTIONS(EVOLUNTIONARY INFLUENCES)
GENETICALLY DETERMINED CHARACTERISTICS
- ALTRUISM
- AGGRESSION
- SEXUAL ATTRACTION
DARWINS THEORY OF NATURAL SELECTION- ASSUMPTIONS(EVOLUNTIONARY INFLUENCES)
- SMALL PROPOTIONOF EACH GENERATION SURVIVES
- VARTAION MEANS THEY ARE NOT IDENTICAL BUT SOME VARIATION CAN BE INHERITABLE
- SOME BEHAVIOURS ALLOW ANIMALS TO SURVIVE
THE EEA- ASSUMPTIONS(EVOLUNTIONARY INFLUENCES)
- LIVED IN SAVANNAHS 2 MILLION YEARS AGO
- MODERN HOMOSAPIENS FORMED 100,000 YEARS AGO
- STILL ADAPTED TO ANCESTORS ENVIRONMENT
- FIGHT/FLIGHT
LOCALISATION OF THE BRAIN- ASSUMPTIONS
- TEMOPROAL = MEMORIES/PROCESSING SOUND
- PRAIETAL= AWARNESS/NAVIGATION/SENSORY INFORMATION
- FRONTAL= BEHAVIOUR AND PERSONALITY (REFERENCE PHINEAS GAGE)
- OCCIPITAL LOBE=INTERPRTING VISUAL STIMULS
- WERNICKES=DIFFICLTLY UNDERSTADING SPEECH
- BROCAS AREA=DIFFICULTY PRODUCING SPEAK
NEUROTRANSMITTERS-ASSUMTION
THIN CELLS CINVEY MESSAGES TO ONE ANOTHER, CHEMICAL MESSANGERS ALLOW BRAIN TO PROCESS THOUGHTS
HOW NEROTRANSMITTERS TRAVEL
ENTER AXON TERMINAL, THEN CHEMICAL REACTIONS IN PRESYNAPTIC VESICLE INHITIATE REALSE OF NEUROTRANSMITTERS WHICH TRAVEL THROUGH SYNAPSE AND ENTER POST SYNAPTIC RECEPTOR SITES TO START THE ELECTRICAL IMPULSE AT DENDRITE OF RECIVING
PSYCHOSURGERY-AIM
TO ERADICATE UNDESIRABLE BEHAVIOUR BY DESTROYING PART OF BRAIN CAUSING BEHAVIOUR
HISTORIC
LEUCOTOMY- Pioneer for this Egaz Moiz, involves drill a hole each side of skull and pulling the instrument called a leuctom to cut and sever the nerve fibers
LOBOTOMY-Pioneer Walter freeman, this is selective destruction of nerve fibers to help alleviate symptoms of mental disorders
STEREOTACTIC
Cingulotomy interrupts brain circuit linking the frontal lobe to deeper structures, surgeons burn away tissue by heating tip of electrodes or use non-invasive tool like gamma knife(focus radiation)
Capsulotomy probes inserted through top of skull to capsule region near the hypothalamus which is part of the circuit
ALTERNATIVE DBS
DBS thread wires through the skull battery is then inserted in the chest & sends high frequency waves to brain
EFFECTIVENESS-PSYCHOSURGERY
+Pippard = 95% of cases no more than slight personality change for 50% of the good results
Ineffective
-lobotomies had 6% fatality & many side effects
-Cosgrove and rauch, cingulotomies treated 56% of OCD patients, capsulotomies treated 67% of OCD patients, cingulotomies treated 65% of major disorders whereas capsulotomies treated 55%
+DBS shows us where and when brain activity takes place
ETHICAL ISSUES-PSYCHOSURGERY
- Rosemary kennedy/howard dully
- Psychological/physical harm(6% fatality rate)
- Risk or harm (irreversible damage due to destroying -parts of the brain)
METHODOLOGY- RAINE ET AL
-Quasi experimental - participants randomly assigned a condition
-IV = NGRI or not, DV = Brain differences
-Matched by age/gender
-41 participants 39 male 2 female mean age of 34.3
-Charged with murder/ manslaughter
-Referred to university of california for ngri defence or history of head injury/drug abuse
-Told to stay medication free for 2 weeks prior to study and tested by urine scan
Control group-
-39 men 2 females/mean age 31.7
-Screened for health physical exam done/medical history taken
-6 schizophrenics matched with 6 schizophrenics from the mental institute
-Controls had no history of psychiatric / physical illness and none were on medication
PROCEDURES-RAINE ET AL
- PET scan used to study participants brain activity
- Pet scan involves FDG
- Brains active sites absorb the FDG,PET scan lets us locate the radioactive areas
- Participants first practice CPT
- Task designed to activate the area of the brain researcher is interested in
- Participants start CPT
- FDG injected after 30 seconds
- 32 minutes later PET scan is done
- 10 horizontal slices of the brain is taken through cortical peel and box technique
FINDINGS REDUCED ACTIVITY
Amygdala, thalamus,prefrontal cortex (part of limbic system so if damaged we don’t learn from our past)
