NeuroBiology Flashcards
What is the function of the Appetitive system?
- how the brain would react to a pleasurable stimuli
- to mediate SEEKING and APPROACH behaviours
What anatomical fts are involved in the Appetitive system?
- ascending DOPAMINE systems
- dorsal striatum (movement)
- amygdala (emotions)
- anterior cingulate (attention/conflict)
- orbitofrontal cortex
Connection to the frontal lobe cortex is intended to ______
bring about reaction to an external stimuli
What is the aversive system?
- it functions to PROMOTE survival in the event of THREAT
What anatomical fts. of the brain is involved in the Aversive System?
- ascending SEROTONIN systems
- amygdala (central nucleus)
- HIPPOCAMPUS
- VA and M hypothalamus
- periaqueductal grey matter
What NTs are involved in the aversive system?
- Noradrenaline
- CRF
- Peptide
How are the systems involved in Depression?
- the altered sensitivity of the brain’s Appetitive system in understanding REWARDs and cues as pleasure
- failure to predict rewards
How are the systems involve in Anxiety?
- altered sensitivity of brain systems evaluating THREAT and CUES predicting danger in an environmen
Why are mood d.os often diagnosed later in adulthood
- it is confused with NORMAL teenage bhaviour, drug use or other psychiatric illnesses
What is the best mode of action for mood disorders?
- early treatment and episode PREVENTION
- better that responding to each new episode
When is depression likely to peak?
-in young childhoos and early adulthood
Why may mood disorders be recurrent?
- abnormal BRAIN development#
- Genetic effects
- endocrine/metabolic causes
- ADVERSE life events (TRAUMA, BAD childhood)
- psychological resilience
- CULTURAL stigma
What occurs with accumulation of the NT ?
-inflammation of the BRAIN or CHANGE in the brain activity mode
Excess of NT is said to be the cause of depression?
- ACh
- Substance P
- CRH - stress hormone
Deficiency of what NT may bring about DEPRESSION?
- NE
- 5-HT
- GABA
- BDNF
- somatostatin
What changes occur with Serotonin in Depression?
- decreased binding of serotonin to the receptors in CORTICAL REGIONS
- reduction in reuptake of serotonin
What occurs with decreased NE neurotransmission?
- Anergia
- Anhedonia
- decreased Libido
What is the link between depression and psychosis?
- dopamine NT
What is the role of Dopamine in addiciton?
- when you like something, the pleasurable stimuli is PICKED up by the Appetitive system
- dopamine is the MAIN NT in this system
What is GABA known to do?
- principle NT in mediating NEURAL inhibition (stops the MISFIRING of neurones)
What is the role of BENZOS and Anti-depressants with GABA?
- benzos INCREASE GABA levels
- anti-depressants UPREGULATE gaba receptors
What occurs in an intact HPA axis? (3)
- CRF relased by the Hypothalamus
- triggers release of ACTH from the PITUITARY
- ACTH acts on the adrenocortical cells and CORTISOL is released from the glands
What is the role of CORTISOL in the body?
- prepares body for fight or flight
- said to RAISE blood glucose levels
What occurs if the negative feedback of Cortisol is impaired?
- continual ACTIVATION of the HPA axis> excess CORTISOL release
