IB Psychology SL Extended Essay Example

The research question is clear, but the wording is still too broad. The student should tighten the age range and define which aspect of bilingualism is being studied, because the current scope invites very different interpretations across studies.

The student opens with a clear definition of bilingualism and immediately frames the topic in psychological terms. This helps the reader understand the scope of the investigation from the outset and gives the essay a focused starting point.

This is asserted too confidently without support. The student should either cite evidence for the frontal-cortex claim or soften the wording, because an unsupported neuroscience statement weakens the accuracy of the topic explanation.

The link between language articulation and cognitive shifting is overstated here. The student should distinguish language development from executive control more carefully, because this kind of broad causal language makes the topic explanation less precise.

This is a strong signposting sentence. The student could make the method even clearer by briefly explaining why these two lines of enquiry were selected and how they compare different populations, since that would sharpen the essay’s focus.

What specific criteria were used to decide which counterstudies to include? Making source-selection rules explicit would strengthen the sense that the investigation was planned rather than assembled opportunistically.

The student connects the study directly to the research question and signals the intended line of argument immediately. This helps the reader see how the evidence is being used rather than merely reported.

The student reports the numbers well, but the methodology behind the comparison is underdeveloped here. The essay would be stronger if it explained what the task measures and why performance on this one task can, or cannot, be generalized to wider inhibitory control.

The methodology is promising here, but the student could be more explicit about why the natural-experiment approach is appropriate. A brief explanation of what it adds beyond a standard cross-sectional comparison would improve method awareness.

This conclusion goes beyond what the study can safely support. The student should avoid implying that bilingualism overcomes developmental language disorders unless the evidence directly tests that claim, because the argument currently overgeneralises from a specific sample.

This is too sweeping as a general claim. The student should qualify it with evidence, because presenting a debated hypothesis as established fact weakens knowledge accuracy.

The terminology is relevant, but the explanation is not clearly tied back to bilingualism or cognitive shifting. The student should explain why these mechanisms matter for the research question instead of listing them generically.

The student demonstrates good command of the topic-specific vocabulary here. To improve further, the essay could define each executive-function term once and then use the terms consistently, so that inhibitory control, cognitive flexibility, and cognitive shifting remain clearly distinct.

The student uses precise quantitative evidence effectively, which strengthens credibility and shows clear understanding of the study’s findings. This is the kind of evidence-based writing that should be repeated throughout the essay.

The student does well to connect a study to a broader theoretical framework. This shows more than factual recall: it demonstrates that the findings are being interpreted through relevant psychological concepts.

This is a plausible interpretation, but it is presented as if it were established by the study. The student should separate observed results from post-hoc explanation more clearly, because that distinction is important for accurate source application.

Does fewer channels and stronger activation necessarily mean more effective cognitive flexibility, or could it also reflect task difficulty or compensation? This is worth unpacking because neural differences do not always translate into better performance.

This is imprecise. A small sample usually reduces statistical power or precision, not statistical significance itself, so the student should use the correct term to show stronger conceptual understanding.

The student is analysing differences between studies rather than simply listing them. This comparative approach is strong because it helps build an argument about moderation and limits, not just separate results.

The inference is too strong for the evidence described. The student should distinguish between a difference observed in a DLD sample and a broader claim that bilingualism overcomes developmental obstacles, because the latter needs much stronger support.

The point is valid, but too vague. The student should specify whether the issue is low power, wide uncertainty, or reduced generalisability, because precise evaluation makes the analysis much more convincing.

This is a useful evaluation point. The student could deepen the analysis by explaining how the control variable affects validity and whether ecological validity might come at the cost of experimental control.

If behaviour does not change, how confident can the student be that the neural pattern reflects a meaningful cognitive advantage? Considering that question would strengthen the evaluation of what the findings actually demonstrate.

This is a strong synthesis statement because it moves beyond individual studies and identifies shared patterns across the evidence base. That kind of aggregation is essential for higher-level critical thinking.

The conclusion is stronger than the evidence presented in the essay allows. The student should align the final judgement more closely with the mixed findings and emphasise moderation and uncertainty rather than stating that the evidence ‘strongly supports’ a broad advantage.

The title clearly signals the topic and age group, so the reader knows immediately what the investigation is about. A concise title like this supports the essay’s overall organisation.

The contents table is helpful because it separates the two thematic bodies of evidence and shows the overall route of the argument. That kind of signposting makes a long essay much easier to follow.

The essay ends with a reference list, which is required and supports academic structure. The student could strengthen the presentation by checking that every in-text citation appears in the bibliography and that the formatting style is consistent throughout.

The essay includes a clear contents page and a logical sequence of sections, which helps the reader navigate the argument easily. This supports readability and shows appropriate extended-essay organisation.

The structure is clear, but this subsection would be stronger if it were more explicitly signposted as a new line of enquiry. A short bridge sentence linking it back to the research question would make the transition more analytical.

The student has included a distinct discussion section, which is good practice. To improve structure further, this section could synthesise the findings more aggressively instead of repeating study-by-study summaries.

The conclusion is structurally appropriate, but the phrasing is repetitive and awkward. The student should streamline the opening sentence so the final section reads with more precision and authority.