| Learning Objective | Essential Knowledge |
|---|---|
2.1.A |
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2.1.B |
|
Cognition
AP Psychology · Topic 2
2.1
Perception
Syllabus
Source: College Board AP Course and Exam Description
Unit 1 ended with sensation, the detection of a stimulus. Perception 知觉 is what the brain does next: it organises and interprets that information. The same signal can be perceived in more than one way.
Two directions of processing work together:
- Bottom-up processing 自下而上加工 starts from the raw sensory information and builds upwards.
- Top-down processing 自上而下加工 starts from what you already expect and know.
Internal filters shape perception. A schema 图式 is a mental framework built from past experience. A perceptual set 知觉定势 is a readiness to see something in a particular way. External filters matter too: context 情境 and cultural expectations change what people report seeing.
Gestalt psychology 格式塔心理学 described how the brain groups parts into wholes: closure 闭合 (filling in gaps), figure and ground 图形与背景 (separating an object from its background), proximity 邻近性 (grouping things that are close), and similarity 相似性 (grouping things that look alike).
Attention 注意 sits between sensation and perception. It is limited, so some information is lost:
- Selective attention 选择性注意 focuses on one input. The cocktail party effect 鸡尾酒会效应 is hearing your own name across a noisy room.
- Inattentional blindness 无意视盲 is failing to see something visible because attention was elsewhere; change blindness 变化盲视 is failing to notice that something has changed.
| English | Chinese | Pinyin |
|---|---|---|
| Perception | 知觉 | zhī jué |
| Bottom-up processing | 自下而上加工 | zì xià ér shàng jiā gōng |
| Top-down processing | 自上而下加工 | zì shàng ér xià jiā gōng |
| schema | 图式 | tú shì |
| perceptual set | 知觉定势 | zhī jué dìng shì |
| context | 情境 | qíng jìng |
| Gestalt psychology | 格式塔心理学 | gé shì tǎ xīn lǐ xué |
| closure | 闭合 | bì hé |
| figure and ground | 图形与背景 | tú xíng yǔ bèi jǐng |
| proximity | 邻近性 | lín jìn xìng |
| similarity | 相似性 | xiāng sì xìng |
| Attention | 注意 | zhù yì |
| Selective attention | 选择性注意 | xuǎn zé xìng zhù yì |
| cocktail party effect | 鸡尾酒会效应 | jī wěi jiǔ huì xiào yìng |
| Inattentional blindness | 无意视盲 | wú yì shì máng |
| change blindness | 变化盲视 | biàn huà máng shì |
2.1
Depth, Constancy, and Movement
Syllabus
| Learning Objective | Essential Knowledge |
|---|---|
2.1.A |
|
2.1.B |
|
Source: College Board AP Course and Exam Description
To perceive a three-dimensional world from a flat retinal image, the brain uses depth cues 深度线索.
Binocular cues 双眼线索 need both eyes. Retinal disparity 视网膜像差 is the small difference between the two images; the greater the difference, the closer the object. Convergence 辐辏 is the inward turn of the eyes for near objects.
Monocular cues 单眼线索 work with one eye: relative clarity 相对清晰度, relative size 相对大小, texture gradient 纹理梯度, linear perspective 线条透视, and interposition 遮挡 (a nearer object blocks a further one).
Perceptual constancy 知觉恒常性 keeps an object looking the same even when its retinal image changes - a door stays rectangular as it swings open. The brain can also perceive apparent movement 似动 when nothing actually moves, which is why a series of still frames looks like a film.
| English | Chinese | Pinyin |
|---|---|---|
| depth cues | 深度线索 | shēn dù xiàn suǒ |
| Binocular cues | 双眼线索 | shuāng yǎn xiàn suǒ |
| Retinal disparity | 视网膜像差 | shì wǎng mó xiàng chà |
| Convergence | 辐辏 | fú còu |
| Monocular cues | 单眼线索 | dān yǎn xiàn suǒ |
| relative clarity | 相对清晰度 | xiāng duì qīng xī dù |
| relative size | 相对大小 | xiāng duì dà xiǎo |
| texture gradient | 纹理梯度 | wén lǐ tī dù |
| linear perspective | 线条透视 | xiàn tiáo tòu shì |
| interposition | 遮挡 | zhē dǎng |
| Perceptual constancy | 知觉恒常性 | zhī jué héng cháng xìng |
| apparent movement | 似动 | shì dòng |
2.2
Thinking and Problem-Solving
Syllabus
| Learning Objective | Essential Knowledge |
|---|---|
2.2.A |
|
Source: College Board AP Course and Exam Description
Concepts 概念 are the basis of thought, and a prototype 原型 is the best example of a concept. People build and change schemas through assimilation 同化 (fitting new information into an existing schema) and accommodation 顺应 (changing the schema to fit new information).
Two ways to solve a problem:
- An algorithm 算法 tries every possible solution and is guaranteed to work, but is slow.
- A heuristic 启发式 is a mental shortcut. It is fast but can lead to error - the representativeness heuristic 代表性启发式 judges by how well something matches a prototype, and the availability heuristic 可得性启发式 judges by how easily examples come to mind.
Thinking can also get stuck. A mental set 心向 is the tendency to repeat a solution that worked before. Functional fixedness 功能固着 is seeing an object only in its usual use. The gambler's fallacy 赌徒谬误 (believing a run must end) and the sunk-cost fallacy 沉没成本谬误 (continuing because of what is already spent) both hinder good decisions.
Executive functions 执行功能 let people generate, organise, plan, and carry out goals. Creativity 创造力 involves divergent thinking 发散思维 (generating many ideas) rather than convergent thinking 聚合思维 (narrowing to one answer).
| English | Chinese | Pinyin |
|---|---|---|
| Concepts | 概念 | gài niàn |
| prototype | 原型 | yuán xíng |
| assimilation | 同化 | tóng huà |
| accommodation | 顺应 | shùn yìng |
| algorithm | 算法 | suàn fǎ |
| heuristic | 启发式 | qǐ fā shì |
| representativeness heuristic | 代表性启发式 | dài biǎo xìng qǐ fā shì |
| availability heuristic | 可得性启发式 | kě dé xìng qǐ fā shì |
| mental set | 心向 | xīn xiàng |
| Functional fixedness | 功能固着 | gōng néng gù zhuó |
| gambler's fallacy | 赌徒谬误 | dǔ tú miù wù |
| sunk-cost fallacy | 沉没成本谬误 | chén mò chéng běn miù wù |
| Executive functions | 执行功能 | zhí xíng gōng néng |
| Creativity | 创造力 | chuàng zào lì |
| divergent thinking | 发散思维 | fā sàn sī wéi |
| convergent thinking | 聚合思维 | jù hé sī wéi |
2.3
Memory Systems
Syllabus
| Learning Objective | Essential Knowledge |
|---|---|
2.3.A |
|
Source: College Board AP Course and Exam Description

Memory is divided by how information is processed.
Explicit memory 外显记忆 can be described to others. It splits into episodic memory 情景记忆 (personal events) and semantic memory 语义记忆 (facts). Implicit memory 内隐记忆 is harder to describe, and includes procedural memory 程序性记忆 (skills such as riding a bike). Prospective memory 前瞻记忆 is remembering to do something later.
Long-term potentiation 长时程增强 is the biological basis: synaptic connections grow stronger with repeated use.
Three models are examinable:
- The multi-store model 多重存储模型 proposes sensory memory 感觉记忆 (including iconic 图像记忆 and echoic 声像记忆 stores), short-term memory 短时记忆, and long-term memory 长时记忆.
- The working memory model 工作记忆模型 treats the middle stage as active, not a waiting room. It has a phonological loop 语音回路, a visuospatial sketchpad 视空间模板, and a central executive 中央执行系统.
- The levels of processing model 加工水平模型 says deeper processing gives better memory: shallow processing of appearance, then sound, then deep processing of meaning.
| English | Chinese | Pinyin |
|---|---|---|
| Explicit memory | 外显记忆 | wài xiǎn jì yì |
| episodic memory | 情景记忆 | qíng jǐng jì yì |
| semantic memory | 语义记忆 | yǔ yì jì yì |
| Implicit memory | 内隐记忆 | nèi yǐn jì yì |
| procedural memory | 程序性记忆 | chéng xù xìng jì yì |
| Prospective memory | 前瞻记忆 | qián zhān jì yì |
| Long-term potentiation | 长时程增强 | zhǎng shí chéng zēng qiáng |
| multi-store model | 多重存储模型 | duō zhòng cún chǔ mó xíng |
| sensory memory | 感觉记忆 | gǎn jué jì yì |
| iconic | 图像记忆 | tú xiàng jì yì |
| echoic | 声像记忆 | shēng xiàng jì yì |
| short-term memory | 短时记忆 | duǎn shí jì yì |
| long-term memory | 长时记忆 | zhǎng shí jì yì |
| working memory model | 工作记忆模型 | gōng zuò jì yì mó xíng |
| phonological loop | 语音回路 | yǔ yīn huí lù |
| visuospatial sketchpad | 视空间模板 | shì kōng jiān mú bǎn |
| central executive | 中央执行系统 | zhōng yāng zhí xíng xì tǒng |
| levels of processing model | 加工水平模型 | jiā gōng shuǐ píng mó xíng |
2.4 2.5
Encoding and Storing
Syllabus
| Learning Objective | Essential Knowledge |
|---|---|
2.4.A |
|
| Learning Objective | Essential Knowledge |
|---|---|
2.5.A |
|
Source: College Board AP Course and Exam Description
Encoding 编码 gets information into memory, and how you encode changes how well you remember.
- Mnemonic devices 记忆术 such as the method of loci 位置法 aid encoding.
- Chunking 组块 groups items into meaningful units, which raises how much short-term memory can hold.
- The spacing effect 间隔效应 shows that spreading study over time beats massed practice 集中练习 (cramming).
- The serial position effect 系列位置效应 means items at the start (primacy 首因效应) and end (recency 近因效应) of a list are remembered best.
Storage differs by system. Maintenance rehearsal 保持性复述 repeats information to hold it; elaborative rehearsal 精细复述 links it to what you already know and works better.
A few people show highly superior autobiographical memory 超常自传体记忆, which suggests biological differences. Storage can also be impaired: Alzheimer's disease 阿尔茨海默病 and infantile amnesia 婴儿期遗忘 both limit what can be stored or recovered.
| English | Chinese | Pinyin |
|---|---|---|
| Encoding | 编码 | biān mǎ |
| Mnemonic devices | 记忆术 | jì yì shù |
| method of loci | 位置法 | wèi zhì fǎ |
| Chunking | 组块 | zǔ kuài |
| spacing effect | 间隔效应 | jiàn gé xiào yìng |
| massed practice | 集中练习 | jí zhōng liàn xí |
| serial position effect | 系列位置效应 | xì liè wèi zhì xiào yìng |
| primacy | 首因效应 | shǒu yīn xiào yìng |
| recency | 近因效应 | jìn yīn xiào yìng |
| Maintenance rehearsal | 保持性复述 | bǎo chí xìng fù shù |
| elaborative rehearsal | 精细复述 | jīng xì fù shù |
| highly superior autobiographical memory | 超常自传体记忆 | chāo cháng zì zhuàn tǐ jì yì |
| Alzheimer's disease | 阿尔茨海默病 | ā ěr cí hǎi mò bìng |
| infantile amnesia | 婴儿期遗忘 | yīng ér qī yí wàng |
2.6 2.7
Retrieving and Forgetting
Syllabus
| Learning Objective | Essential Knowledge |
|---|---|
2.6.A |
|
| Learning Objective | Essential Knowledge |
|---|---|
2.7.A |
|
Source: College Board AP Course and Exam Description
Retrieval takes two forms: recall 回忆 (producing information without cues) and recognition 再认 (identifying it among options). Recognition is easier, which is why a multiple-choice question feels easier than an essay.
Retrieval improves with matching conditions. Context-dependent memory 情境依存记忆 works better in the same place; state-dependent memory 状态依存记忆 works better in the same physical state; mood-congruent memory 心境一致性记忆 recalls material matching your current mood. Practising retrieval helps too - the testing effect 测试效应 shows that testing yourself beats rereading.
Forgetting has several causes. The forgetting curve 遗忘曲线 shows loss is fastest right after learning. Encoding failure 编码失败 means it never got in. Interference 干扰 can be proactive 前摄干扰 (old learning blocks new) or retroactive 倒摄干扰 (new blocks old). Retrieval failure 提取失败 includes the tip-of-the-tongue phenomenon 舌尖现象.
Memory is also reconstructive 重构的, not a recording. The misinformation effect 错误信息效应 occurs when later information changes what a person remembers. Source amnesia 来源遗忘 is remembering the information but not where it came from.
Worked example (a real AP exam question). The 2025 Article Analysis Question presented a study in which participants read a summary containing 20%, 50% or 80% misleading sentences, then answered questions about a video. Correct responses fell from 74% (low misinformation) to 63% (high). One part asked students to "Explain how at least one of the research findings supports or refutes the misinformation effect." A full-mark answer states the finding and connects it to the concept: "Participants in the high misinformation condition answered 63% correctly compared with 74% in the low condition. Because exposure to more misleading detail lowered accuracy, the finding supports the misinformation effect, in which information received after an event changes the memory of it." Notice the shape: quote the data, then name the concept the data supports. A restated definition with no number does not answer Explain.
| English | Chinese | Pinyin |
|---|---|---|
| recall | 回忆 | huí yì |
| recognition | 再认 | zài rèn |
| Context-dependent memory | 情境依存记忆 | qíng jìng yī cún jì yì |
| state-dependent memory | 状态依存记忆 | zhuàng tài yī cún jì yì |
| mood-congruent memory | 心境一致性记忆 | xīn jìng yí zhì xìng jì yì |
| testing effect | 测试效应 | cè shì xiào yìng |
| forgetting curve | 遗忘曲线 | yí wàng qū xiàn |
| Encoding failure | 编码失败 | biān mǎ shī bài |
| Interference | 干扰 | gān rǎo |
| proactive | 前摄干扰 | qián shè gān rǎo |
| retroactive | 倒摄干扰 | dào shè gān rǎo |
| Retrieval failure | 提取失败 | tí qǔ shī bài |
| tip-of-the-tongue phenomenon | 舌尖现象 | shé jiān xiàn xiàng |
| reconstructive | 重构的 | zhòng gòu de |
| misinformation effect | 错误信息效应 | cuò wù xìn xī xiào yìng |
| Source amnesia | 来源遗忘 | lái yuán yí wàng |
2.8
Intelligence and Testing
Syllabus
| Learning Objective | Essential Knowledge |
|---|---|
2.8.A |
|
2.8.B |
|
2.8.C |
|
2.8.D |
|
Source: College Board AP Course and Exam Description
Psychologists still disagree about how to define intelligence 智力. Spearman's g 一般智力因素 proposes one general ability; other theories propose several, including fluid intelligence 流体智力 (reasoning with novel problems, which declines with age) and crystallised intelligence 晶体智力 (accumulated knowledge, which does not).
Early tests produced an intelligence quotient (IQ) 智商 by dividing mental age by chronological age. Modern scores are compared with a normal curve 正态曲线 of the population.
Any psychological assessment must meet psychometric principles 心理测量学原则:
- Standardization 标准化 - the test is given under consistent procedures and scored against a comparison group.
- Validity 效度 - it measures what it claims to. Construct validity 构念效度 and predictive validity 预测效度 are both examinable.
- Reliability 信度 - it gives similar results each time, checked by test-retest reliability 重测信度 and split-half reliability 分半信度.
IQ scores have risen worldwide over generations (the Flynn effect 弗林效应), which points to societal rather than biological causes. Scores vary more within groups than between them, and stereotype threat 刻板印象威胁 can lower performance when a person fears confirming a negative stereotype about their group.
| English | Chinese | Pinyin |
|---|---|---|
| intelligence | 智力 | zhì lì |
| Spearman's g | 一般智力因素 | yì bān zhì lì yīn sù |
| fluid intelligence | 流体智力 | liú tǐ zhì lì |
| crystallised intelligence | 晶体智力 | jīng tǐ zhì lì |
| intelligence quotient (IQ) | 智商 | zhì shāng |
| normal curve | 正态曲线 | zhèng tài qū xiàn |
| psychometric principles | 心理测量学原则 | xīn lǐ cè liáng xué yuán zé |
| Standardization | 标准化 | biāo zhǔn huà |
| Validity | 效度 | xiào dù |
| Construct validity | 构念效度 | gòu niàn xiào dù |
| predictive validity | 预测效度 | yù cè xiào dù |
| Reliability | 信度 | xìn dù |
| test-retest reliability | 重测信度 | zhòng cè xìn dù |
| split-half reliability | 分半信度 | fēn bàn xìn dù |
| Flynn effect | 弗林效应 | fú lín xiào yìng |
| stereotype threat | 刻板印象威胁 | kè bǎn yìn xiàng wēi xié |
2.8
Exam tips
- Keep sensation and perception apart: detecting is sensation, interpreting is perception.
- Bottom-up starts with the stimulus; top-down starts with expectation. Say which the scenario shows.
- Learn the interference pair by direction: proactive means old material acts forward onto new.
- For encoding questions, name a specific strategy - chunking, spacing, elaborative rehearsal - not "studying harder".
- On testing questions, separate reliability from validity. A test can be reliable and still measure the wrong thing.
- When data are given, quote a figure before naming the concept. Findings-based parts award the link between the number and the term.
Interactive lessons on this topic
Work through it step by step, with instant-check exercises.