IB Psychology SL Extended Essay Example

The research question is clearly stated and gives the essay a defined direction by naming the population, intervention, and intended outcome. This makes the topic immediately understandable and gives the reader a clear expectation of what evidence should be judged.

The wording slightly overreaches by pairing cognitive decline with slowing disease progression. The studies mainly test symptom change on cognitive scales, so the question should be narrowed unless the essay can provide stronger evidence of disease-modifying effects.

The introduction does a good job of orienting the reader to the investigation before the body begins. That organisation helps make the report easy to follow and shows a deliberate approach to structure.

This background becomes too broad and begins to drift away from the specific focus on acetylcholinesterase inhibitors. The student should tighten the opening by prioritising only the neuroscience needed to explain the treatment mechanism and avoid extended general description that does not directly support the research question.

The methodology becomes less focused here because the essay expands from the named inhibitor class into memantine and other alternatives without stating a clear comparison framework. The student should explain why each source category is included and how it serves the exact research question.

What standard is being used to decide which treatment is “most effective” here: symptom improvement, duration of benefit, side-effect burden, cost, or real-world quality of life? Naming the comparison criteria would make the focus much sharper.

Consider briefly justifying why these studies were chosen and how they are being ranked in the discussion. A short methodological rationale would make the source selection look more deliberate and improve the coherence of the investigation.

The student shows solid subject knowledge by linking beta-amyloid plaques to disrupted synaptic function. This kind of mechanism-based explanation helps the reader understand why acetylcholinesterase inhibitors might matter in Alzheimer’s treatment.

This sentence mixes useful background with overgeneralised claims and awkward scientific phrasing. The student should separate the roles of neurons, astrocytes, and microglia more cleanly and avoid statements that suggest these glial cells simply prevent all protein buildup.

This explanation is imprecise: synapses do not simply “inhibit responses from the recipient neuron.” The student should use more accurate neurobiology language to describe excitatory and inhibitory signalling, because conceptual accuracy is essential when explaining treatment mechanisms.

The mechanism is partly correct but too vague. The student should specify that donepezil inhibits acetylcholinesterase, rather than using the broad phrase “restoring the balance of neurotransmitters,” which is not precise enough for a psychology/science investigation.

It would strengthen the investigation to briefly connect these measures to the actual research question. For example, the student could state whether each test captures short-term symptomatic change, functional ability, or longer-term decline.

The description is broadly useful, but the wording should be more accurate: the MMSE is a screening tool rather than an “in-depth” test. Precision matters here because the evaluation later relies on these measures as evidence of effectiveness.

The student correctly introduces the key assessment tools before the study summaries, which shows good knowledge of how treatment effects are measured in this field. This helps the later analysis because the reader knows how to interpret the reported score changes.

This description is scientifically unclear. Butyrylcholinesterase is not best described as an enzyme that “detoxif[ies] neurons,” so the student should verify the mechanism and rewrite it with more accurate terminology.

This result is presented without enough explanation of what the score changes mean in practical terms. The student should clarify whether these differences are clinically meaningful, not just statistically positive, so the source is applied more critically.

This is a strong example of source application because the student does not just report the findings but also evaluates the design. Recognising open-label bias shows clear understanding of why methodology affects confidence in the evidence.

The study is compared to earlier drug trials without adequately controlling for differences in population, duration, or design. The student should avoid direct cross-study equivalence unless the measures and methods are comparable, otherwise the interpretation becomes too speculative.

This explanation simplifies memantine too far and makes its mechanism sound non-specific. The student should distinguish clearly between acetylcholinesterase inhibitors and NMDA receptor antagonism, because source application depends on accurate treatment comparison.

This animal evidence should be handled much more cautiously. The student should avoid using a mouse study as direct support for human treatment effectiveness unless the limits of animal-to-human transfer are explicitly foregrounded.

The student begins to move from summary into interpretation by relating the follow-up period to treatment durability. This is useful analysis because it connects the study result to the broader question of sustained benefit.

The comparison is too brief to count as strong analysis. The student should explain how the larger sample and longer follow-up change confidence in the conclusion, rather than simply stating that the results were similar.

This is a useful result, but the analysis does not yet explain why a dose-response pattern matters. The student should discuss whether higher doses also increased side effects, because treatment effectiveness must be balanced against tolerability.

The student identifies an important tension between quantitative scores and real-world observation, but the conclusion is still underdeveloped. The essay should explain what this mismatch suggests about the limitations of the outcome measures instead of only noting that the study disagrees with earlier findings.

The analysis risks overstating a small score change. The student should distinguish between statistical change and meaningful clinical benefit, especially when the numerical difference is modest and the study is being used to compare treatment options.

This claim is plausible, but it is asserted more strongly than the evidence shown here justifies. The student should tie the statement more directly to the specific article’s findings and avoid generalising from mechanism-based reasoning alone.

The use of a mouse model is informative, but the analysis should explicitly separate preclinical evidence from human treatment evidence. Without that distinction, the essay risks treating animal findings as if they directly answer the question about older adults.

The student is making an evaluative move by considering ethics across the body of research rather than study by study only. That broader lens is helpful because it shows the investigation is not purely descriptive.

This is a major conceptual problem: cognition is the dependent variable, not the independent variable. The student should correct the variables and then explain how control improves internal validity, otherwise the evaluation rests on an inverted research-design claim.

The evaluation would be stronger if it distinguished between necessary exclusion criteria and genuine sampling bias. Some exclusions are methodologically justified, so the student should explain when strict criteria improve control and when they reduce generalisability.

This is a good evaluative point, but it needs to be linked more tightly to the essay’s final judgement. The student should explain how the limitations of MMSE, ADAS-Cog, and CIBIC-plus affect confidence in the overall conclusion about treatment effectiveness.

If a score improves but day-to-day functioning does not change, should that still count as meaningful evidence that a treatment is effective? Answering that question explicitly would strengthen the argument about clinical significance.

This is stronger than the evidence supports. The student should avoid an absolute recommendation and instead compare which treatments appear more suitable for which patients, based on severity, side effects, and evidence quality.

This final judgement is not sufficiently supported by the earlier evidence, especially because one of the main exercise sources is an animal study. The student should either narrow the claim or provide stronger human evidence before making such a definitive comparison.

The conclusion is too definite given that much of the evidence is about symptom improvement rather than preventing progression. The student should qualify the claim more carefully so it matches the actual scope of the studies reviewed.

The reference section is signposted, but the page range appears unfinished. The student should check that the contents page and section labels are complete and consistent so the structure looks fully controlled.

The report has a clear overall structure with a contents page that guides the reader through the introduction, body, discussion, conclusion, and references. That organisation improves readability and shows awareness of essay conventions.

The conclusion continues onto a later page and the final judgement feels somewhat extended. A tighter ending that closes the argument on the same page would make the structure feel more purposeful and polished.

Consider standardising the reference list into one consistent citation style throughout. That would make the academic presentation look more polished and would also make the sources easier to verify.

Two references are run together here, which makes the bibliography harder to read and verify. The student should separate each entry cleanly and ensure that punctuation and line breaks consistently mark where one source ends and another begins.