Cognition

Notes

Perception

• Bottom-up processing builds a perception from raw sensory details. Top-down processing uses expectations and experience.
• Perceptual set and schemas shape what we see. Gestalt principles (closure, proximity, similarity, figure-ground) describe how we group things.
• Depth cues: binocular (retinal disparity, convergence) and monocular (relative size, interposition, linear perspective, texture gradient).
• Selective attention, inattentional blindness (missing an unexpected object) and change blindness.

Thinking and problem solving

• Algorithms guarantee a solution; heuristics are mental shortcuts. The availability heuristic judges likelihood by how easily examples come to mind; the representativeness heuristic judges by how well something matches a prototype.
• Biases: confirmation bias (seeking agreeing evidence), framing (wording changes choices), anchoring, hindsight bias, overconfidence, functional fixedness, mental set, and the sunk-cost fallacy.
• Convergent thinking finds one answer; divergent thinking generates many (creativity).

Memory

• Encoding → storage → retrieval. The multi-store model: sensory memory → short-term (working) memory → long-term memory.
• Working memory holds about $7 \pm 2$ items briefly; chunking helps. Rehearsal (especially elaborative rehearsal, connecting to meaning) moves information into long-term memory. Deep processing beats shallow processing.
• Long-term memory: explicit (episodic and semantic) and implicit (procedural skills and priming).
• Retrieval cues: recall vs recognition, context-dependent and state-dependent memory, the serial position effect (primacy and recency).
• Forgetting: the forgetting curve (Ebbinghaus), proactive interference (old blocks new), retroactive interference (new blocks old), and encoding failure.
• Memory is reconstructive: the misinformation effect and false memories. Spacing practice (distributed practice) and the testing effect improve learning.
• Amnesia: anterograde (can't form new memories) and retrograde (lose old memories).

Intelligence

Spearman's general intelligence (g), Gardner's multiple intelligences, Sternberg's triarchic theory, and fluid vs crystallized intelligence. Good tests are reliable (consistent) and valid (measure what they claim). Stereotype threat can lower test performance.