Lec 12 and 13 - Flashcards

Question

Young et al. (1985) - Used homeless men

Answer 1

Used homeless men so their depressed moods were Probably quite high because of their situation 3 conditions: Fed participants pure amino acids in a drink 1) The amino acid mixture had all but tryptophan 2) control drink which is used to balance amino acid 3) drink had addition of typtophan. A cognitive task was used to measure if mood was effected. They performed this under diff levels of distractibility. 5 hours after treatment =Tryptophan depletion caused higher depression scores and these people had lowest plasma tryptophan (24% below baseline) =when they are depressed participants were more distracted by the dysphoric theme (heard things congruent with low mood) =when tryptophan was added, they perform better on dysphoric theme condition than low and high distraction

Answer 2

Fish, sea food and particularly oily fish and cod liver oil AKA Omega-3 fatty acids ``` Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA)) These are long chain fatty acids ``` DHA - 22:6n-3 -is a long chain polyunsaturated fatty acid. (22 means is that 22 carbon atoms in chain, the 6n means it has 6 double bonds which is why it is unsaturated. Any fatty acid that has more than 1 double bond it is a polyunsaturdated bond. The 3 is because the first double bond occurs 3 bonds away from omega molecule The n-6 and n-3 are families of polyunsaturated fatty acids

Answer 3

The alpha-linolenic acid – n-3 is grape seed. The origin of consumption for linoloeic n6 is through sunflower and palm oil which are primary saturated acid but also has linoleic acid. n3 - EPA then DHA - the rate of alpha-linolenic acid (ALA),to DHA is slow n6- Arachildonic acid then DPA The amount of n-6 can influence synthesis of n-3 because they use same enzymes The ratio of n6 to n3 is important in our diets.

Answer 4

Consumption of high amounts of n3 fatty acids means there are more incorporated into cell membrane. The nature of those fatty acids can in turn effect cell membrane function and hormone neurotransmitter function through influencing receptors embedded in cell membrane.

Answer 5

declining dietary intakes of omega-3 fatty acids relative to omega-6 intake

Answer 6

DHA is the most abundant n-3 fatty acid in the human brain. present in fish and sea foods (and poultry and eggs are also significant sources) and especially alpha-linolenic acid (ALA), which is present in soybean, rapeseed (canola) and flax oils, and some nuts Concentration can affect neural membrane function (and thereby speed of signal transduction, and neurotransmission) DHA is involved in neurogenesis, and metabolites of DHA have neuroprotective activity Rate of synthesis of DHA from ALA is generally low and is higher in women and during pregnancy - DHA is present in breast milk and concentration is influenced by the amount of DHA in the mother’s diet

Answer 7

``` Cognitive development Visual acuity Cognitive decline, including Alzheimer’s disease ADHD Dyspraxia / DCD Dyslexia Asperger’s syndrome and autism Aggression and impulsivity Schizophrenia Depression, including postpartum depression ```

Answer 8

Breast milk has higher levels of DHA than raw cows milk and is therefore better for us. Rate of increase in DHA in the brain (relative to brain weight) is greatest during foetal development and early infancy Cognitive function better at 6-23 months of age in children who were previously breast fed but the research doesn’t show a clear effect of DHA on its own

Answer 9

Children, aged 5-12 years, with developmental co-ordination disorder (DCD) given either 558 mg EPA, 174 mg DHA, 9.6 mg vitamin E per day or Placebo, olive oil Outcome at 3 months : =Motor skills, no difference between fish oil and placebo =Performance on reading and spelling tests, and teacher ratings of ADHD symptoms improved more for those receiving fish oil Addition of vitamin E could have influenced results Also had specialized sample so not generalisable to all children Also - they did not match pp at baseline, the real difference is at baseline – the fish oil group by chance was lower. Therefore could be regression to the mean effect – the groups could be quite similar.

Answer 10

Looked at baseline reading score, 33rd centile, 20th centile and 10th centile = found benefit gained over 16 week period in terms of reading ability for those performing the worst (worst 10% in study showed benefit) But when you include all of the children (33rd) there is no sig effect So if the worst performing children are getting a benefit, but as group they aren’t, then this group must be doing slightly worse on placebo so there could be a neg effect of consuming fish oil for top-performing 80% of the population

Answer 11

the more fish eaten, the lower rates of depression (eg iceland eat more and have less depression) - however cant infer cause.

Answer 12

Patients with bipolar disorder whose conventional treatment was proving uneffective so they were treated with fatty acids. They were treated with their normal treatment too =found clear evidence of positive outcome when given huge amounts of fatty acids relative to normal diet =2 out of 4 outcomes were sig - these were hamilton rating scale for dep and clinical global impresssion scale

Answer 13

18 trials on fish oil supplementation and depression used Duration of supplementation 28 to 180 days Supplement given alone or as adjunctive treatment And range of measures for depression when put into forest plot, there is a small, just significant benefit of fish oil supplementation findings were influenced by one large study in which Pp were told to increase fatty acids in diet and primary outcome was heart disease. But dep was also measured. If this study is removed, the effect size would be bigger in favour of fatty acids.

Answer 14

General population was of interest, not clinically depressed just moderately dep. They supplemented levels of EPA and DPA that is equivalent to diet just slightly higher in ratio of what is consumed. these were the groups: EPA, DHA, EPA+DHA, olive oil, vitamin e, orange oil recieved either with EPA+DHA or placebo primary outcome measure was DASS - self-report depressed mood at 4 and 12 weeks =found a small effect of the supplement =No effect of supplementation in people who started with higher depressed mood =no effect on Beck Depression Inventory concluded where benefits were found the participants had more severe depression, but these findings were small therefore was a null effect and no benefit

Answer 15

Children who eat a healthy breakfast are more likely to do well in assessment Unhealthy foods have no positive effect A direct link has been found between breakfast quality and educational attainment