CLPS 0610 - Midterm 1 Experiments

What did Dunn et al. (1991) study, and what were the findings?

Examined dinner conversations between parents, a 3-year-old, and a 1-year-old sibling. Found that parents who discussed mental states more had 3-year-olds who passed the false belief task. Follow-up study confirmed this effect when the 1-year-olds were tested at 3 years old (longitudinal study).

What was Needham et al. (1997) testing in infants?

Investigated whether 8-month-olds segment objects based on perceptual features. Infants stared longer when objects that should move separately instead moved together, indicating they perceived them as separate objects.

What was the key finding of Kellman and Spelke (1983) on motion segmentation?

4-month-olds were habituated to a moving rod behind an occluder. When shown a whole rod vs. two separate rod pieces afterward, they dishabituated to the broken rod, suggesting they perceived the occluded rod as one object based on motion.

What does the Kellman and Spelke (1983) study suggest about object perception in infants?

Infants may have an innate ability to segment objects using motion cues, though it’s also possible they learned this in the first 4 months.

How did Regolin and Vallortigara (1995) extend Kellman & Spelke’s findings?

Replicated the motion segmentation study using chickens, supporting the idea that innate perceptual abilities are evolutionarily ancient.

What did Slater et al. (1990) find when replicating Kellman & Spelke’s study with newborns?

Newborns failed the segmentation-by-motion task, dishabituating to the whole rod instead of the broken rod. This suggests motion-based segmentation is not innate but develops with experience.

How did Yonas (1981) test infant depth perception, and what did he find?

Used the shadowcaster experiment:

• 1-month-olds did not react when a shadow approached.

• 3-4-month-olds showed distress.

• Poor depth perception in newborns may explain why they fail object occlusion tasks.

What did Valenza, Leo, Gava, and Simion (2006) discover about infant vision and motion perception?

• Newborns only have the visual pathways for saccades (jerky eye movements), not smooth pursuit (tracking motion).

• Replicated Kellman & Spelke (1983) using saccades instead of smooth pursuit, and newborns finally saw the rod as continuous, showing that motion perception depends on eye movement development.

What did Meltzoff and Moore (1977) find about imitation in newborns?

• Infants as young as 24 hours old imitated facial expressions (e.g., sticking out tongue).

• Suggests an innate ability for episodic memory and facial perception ("adult is like me").

What did Rovee-Collier (1999) study about infant memory?

• 2-month-olds learned that kicking made a mobile move and remembered for 1 day.

• 6-month-olds remembered for 2 weeks.

• Memory lasted longer if the mobile was jostled (a retrieval cue).

• Relearning doubled memory duration.

How did Meltzoff and Borton (1979) show early sensory integration?

• 1-month-olds sucked on a uniquely shaped pacifier, then saw an image of two pacifiers.

• They looked longer at the one they had sucked on, indicating early sensory integration between touch and vision.

What did Quinn et al. (2001) test about infant categorization?

• Between categories: Newborns looked longer at a new category shape (triangle vs. square).

• Within category: Newborns distinguished between different shapes within the same category.

• Generalization: 3-4 month-olds grouped similar objects into categories, newborns did not.

• Suggests categorization abilities develop with age and experience.

What did Dunn et al. (1991) study about dinner conversations and false belief tasks?

Parents who discussed mental states more had 3-year-olds who passed the false belief task. The study was longitudinal—following the same children from age 1 to age 3.

What did Needham et al. (1997) discover about segmentation by features?

8-month-olds were shown a touching box and slinky. They stared longer when they moved together, showing they expected them to be separate objects.

What did Kellman & Spelke (1983) find about segmentation by motion?

4-month-olds were habituated to a rod moving behind an occluder. They dishabituated to a broken rod, suggesting they perceived it as a single object.

How did Slater et al. (1990) challenge Kellman & Spelke (1983)?

They found that newborns did not perceive the rod as one object, suggesting segmentation by motion is learned rather than innate.

How did Valenza et al. (2006) modify the Kellman & Spelke experiment, and what did they find?

They used saccades instead of smooth pursuit eye movement, showing that newborns then perceived the rod as continuous.

What did Meltzoff & Moore’s (1977) study on neonatal imitation show?

Newborns (under 24 hours old) could imitate facial expressions, indicating an innate capacity for episodic memory and cross-modal mapping.

What did Rovee-Collier (1999) discover about infant memory with the mobile task?

2-month-olds remembered for 1 day; by 6 months, memory lasted 2 weeks. Relearning or reminders extended memory.

What did Meltzoff & Borton (1979) show about cross-modal perception in infants?

1-month-olds sucked on a pacifier (either smooth or bumpy) and later preferred looking at the one they had sucked on, showing early sensory integration.

How did Quinn et al. (2001) test infants' ability to categorize shapes?

Infants could distinguish between triangles and squares (between-category), but only older infants (3-4 months) generalized across category members.

What did Younger (1992) find about infants detecting correlations between features?

10-month-olds noticed when feature correlations were violated, but 7-month-olds did not.

How did Kirkham et al. (2002) show statistical learning in infants?

Infants as young as 2 months noticed predictable patterns in shape sequences and dishabituated when patterns were violated.

What was Michotte’s (1962) finding on causal perception in adults?

Adults perceived direct launching (one ball hitting another and causing it to move) as causal but not delayed launching.

How did Leslie & Keeble (1987) modify Michotte’s experiment for infants?

6.5-month-olds dishabituated more to reversed direct launching than reversed delayed launching, suggesting an early understanding of causality.

How did Oakes (1994) refine Leslie & Keeble’s (1987) study?

She added a no-contact condition and found that 7-month-olds distinguished causal vs. non-causal, whereas 6-month-olds did not.

What did Gergely et al. (1995) find about goal-directed behavior in infants?

12-month-olds expected an efficient movement (ball hopping only when a barrier was present), suggesting early understanding of rational action.

What did Somerville & Woodward (2005) find about action and perception?

8-month-olds who pulled a cloth to get an object also looked longer at a violation of expectation event, linking motor actions to causal expectations.

What did Wu et al. (2011) discover about segmentation and statistical learning?

8-month-olds noticed when objects moved in ways that violated previously learned statistical structures.

What did the Drawbridge Study demonstrate about object permanence?

4-5-month-olds dishabituated when a rotating drawbridge moved through a hidden object, suggesting they expected object solidity.

What did Xu & Carey (1996) find about spatiotemporal vs. property-based object individuation?

10-month-olds needed to see both objects at the same time to understand they were different, while 12-month-olds could use properties alone.

What did Spelke et al. (1992) find about infants’ understanding of object solidity?

4-month-olds stared longer when a ball was shown under a solid platform, suggesting they understood solidity violations.

How did Sitskoorn & Smitsman (1995) test infants' understanding of containment?

By 6 months, infants dishabituated to impossible containment events, but 4-month-olds didn’t understand containment relationships.

What did Hespos & Baillargeon (2001) show about infants distinguishing occlusion from containment?

4.5-month-olds noticed occlusion violations, but not containment violations until 7.5 months, suggesting different developmental timelines.

What did Meltzoff (1995) discover about infants imitating failed actions?

15-18-month-olds imitated the goal rather than the action (e.g., successfully pulling apart a tinker toy when they had seen an adult fail).

How did Meltzoff (1995) show infants attribute intentionality to humans but not robots?

Infants imitated failed human actions but did not imitate failed robotic actions, suggesting they perceived intention in human actors.

In Antell & Keating (1983), newborns were habituated to dot displays with the same quantity but different spacing. How did they respond when shown a new quantity with preserved spatial properties?

They dishabituated to small number changes (1, 2, 3) but not to larger ones (4 vs. 6, 6 vs. 4).

In Xu & Spelke (2000), 6-month-olds were shown displays of 8 vs. 16 and 8 vs. 12. Which numerical differences could they detect?

They distinguished 8 vs. 16 but not 8 vs. 12, showing sensitivity to large differences.

In Starkey, Spelke, & Gelman (1983), 7-month-olds saw either 2 or 3 shapes while hearing 2 or 3 drumbeats. What did the infants prefer?