Sample enters (1s)

Boxes enter (1s)

Ellipse moves to center. Response

interval (0.5s or 2s)

Using object history to predict future behavior: are young infants essentialists?Chen Cheng, Zsuzsa Kaldy, Sangya Dhungana, Erik Blaser

Developmental and Brain Sciences, University of Massachusetts Boston, Boston, MA

Test trials

Will a more naturalistic ‘morph’ transition encourage essentialism while a spatiotemporal discontinuous

‘replacement’ will discourage it?

Background• Preschool-age children show essentialism (Gelman,

2003), ascribing an essence to an animated object that includes its history, and which can determine behavior.

• Infants show the precursors of essentialism:• Object invariance (9-month olds; Ruff, 1978);• Maintaining object representations during occlusion

(6-month-olds; Kaufman, et al., 2005);• Resisting individuating two disparate appearances

of an object, when shown that one can change into the other (14-month-olds; Cacchione et al., 2013).

How do people track an object’s identity even when its appearance changes?

We hypothesize that some natural transitions facilitate tracking identity, while other transitions, like

spatiotemporal discontinuities, impair it.

Introduction

HUMAN VISION LAB

Methods Results

Discussion

Acknowledgement & References

• 9-month old infants performed better when the object transition happened naturally (Morph), rather than in magical, discontinuous transition (Replace).

• We think that our natural-looking object transformation (Morph) helped infants to maintain object representations, and to track object identities. Thus, it provided evidence for an essentialist stance in 9-month-old infants.

• Further analysis will compare participants’ attentional engagement (general looking time, pupil dilation) in the two conditions.

• Further research aims to study the role of agency and language (e.g., verbal labels) in maintaining the object identity when transition happens.

This project was supported by NIH #1R15HD086658 and Grant #319294 from the Simons Foundation under the auspices of the Simons Center for the Social Brain at MIT.Blaser, E., Pylyshyn, Z. W., & Holcombe, A. O. (2000). Tracking an object through feature space. Nature, 408(6809), 196-199. Cacchione, T., Schaub, S., & Rakoczy, H. (2013). Fourteen-month-old infants infer the continuous identity of objects on the basis of nonvisible causal properties. Developmental Psychology, 49(7), 1325. Gelman, S. A. (2003). The essential child: Origins of essentialism in everyday thought. Oxford University Press, USA. Kaufman, J., Csibra, G., & Johnson, M. H. (2005). Oscillatory activity in the infant brain reflects object maintenance. Proceedings of the National Academy of Sciences of the United States of America, 102(42), 15271-15274.For more info, please contact (Chen.Cheng001@umb.edu); or (Erik.Blaser@umb.edu).

Participants

30 8- to 10.5-month olds were randomly assigned to Morph condition (N = 15, Mean = 9.17) and Replace

condition (N = 15, Mean = 9.01).

MorphCondition

Procedure: 12 Training trials (6 with 0.5s delay, 6 with 2s delay), followed by 12 Test trials.

1) At-chance performance at the beginning of test.

2) Performance in Morph improves quickly and stays above chance while not in Replace.

Performance over time

Maintaining identity in spite of changes in appearance provides useful constancy in an environment where objects age, mutate, adorn, and deform.

ReplaceCondition

Transition period (3s)

Critical period for

anticipatory saccades

Boxes enter (1s)

The two transitions are as similar as possible; the difference may be visually subtle, but cognitively

relevant.

Dependent measure: anticipatory saccade to ‘match’ (correct) vs. ‘non-match’ box during response interval

MatchNon-match

1) Comparison between conditions: participants in Morph condition performed significantly better than participants in Replace condition (t = 3.06, p = 0.008).

2) Comparison between task performance and chance performance:

• Participants in Morph performed significantly better than chance (= 0.5) performance (t = 2.64, p = 0.02);

• Performance in Replace was not different from chance.

Overall performance

1

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

0

Prop

ortio

n of

Per

form

ance

bas

ed o

n fir

st lo

oks

Morph

Replace

Training

n.s.n.s.

p<0.05

1

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

01 2 3 4

Prop

ortio

n of

Per

form

ance

bas

ed o

n fir

st lo

oks

Test trials

Training trials

“Slough off”

“Disappear and reappear instantly”

1-3 4-6 7-9 10-12

Ellipse moves to center. Response interval (2s)

Ellipse moves to ‘match’. Reward (1.5s)

Ellipse moves to ‘match’. Reward (1.5s)