Perceptual and Memory Development Flashcards
Week 10 (26 cards)
Reflexes, Balance, and Action: How Perception and Movement Develop Together
Reflexes are early movements that help babies interact with their body, mind, and environment.
Balance is an active process—it requires the body to work together with what we see and sense in the world.
Visual flow fields (patterns of motion we see) help us keep balance. If this visual info is disrupted, it can make babies lose balance.
Held & Hein (1963) showed that only active movement with visual input helps animals develop normal visual-motor skills. Passive viewing isn’t enough.
Reaching and Understanding Intentions
Infants start reaching at 3 months, but they’re not very skilled yet.
Libertus & Needham (2010) used “sticky mittens” to help babies grasp things earlier.
This experience helped babies not only reach better—but also understand goal-directed behavior in others.
Sommerville et al. (2005) found that babies who used sticky mittens recognized adult actions as intentional (e.g., reaching for a ball), while those without mittens did not.
Visual perception does not work like a camera, yes or no
Yes
Vision is active , take all previous knowledge to understand what we are perceiving
Categorical perception
Tendency to group incoming sensory information that exists along a continuum into discrete categoriesCategorical Perception (Visual Example):
Even though colors change gradually across the rainbow, we see them as separate categories like “blue,” “green,” or “yellow.”
🔵🟢 For example: A tiny change in shade might not be noticed if it’s within “blue,” but if it crosses the blue–green boundary, we suddenly see it as a different color — even if the change is the same size.
👉 Our brain creates boundaries in a smooth continuum.
Perceiving Faces
Faces important stimuli
Withing hours, babies have preference for their mothers face
Barnyard chickens seem to have an innate ability to recognize threats based on movement and shape.
🦅 For example: Chicks react with fear to a hawk-like shape moving overhead—even if they’ve never seen a predator before.
Key Idea:
This suggests they may be “wired” from birth to detect danger—no learning required.
At 3 months of age- preference for well-propionate faces over distorted ones.
Preference for faces of the ethnic group that they are surround by- not about the race of the baby
At 6 months of age- infant can discriminate between different human faces and different monkey faces equally well
At 9 months- ability to discriminate human faces improves, while the ability to discriminate monkey faces decreases, due to experience
Perceptual Narrowing
A developmental process where babies become better at noticing familiar things and worse at noticing unfamiliar ones.
Example:
👶 At 6 months, babies can tell apart monkey faces, but by 9–12 months, they usually lose that ability—unless they’ve seen lots of monkey faces.
Key Idea:
The brain fine-tunes perception based on what it sees often—and drops sensitivity to things it rarely experiences.
Audio perception does not work like a mic, yes or no
YEs
Speech Perception
A phoneme is the smallest unit of sound in spoken language (like “b,” “a,” “th”).
English has about 40–45 phonemes.
We combine them to make words and phrases.
Phoneme Challenge:
Pronunciation isn’t always clear—people speak at different speeds, tones, and sloppiness.
Co-articulation means your mouth shape is influenced by:
What you just said
What you’re saying now
What you’re about to say
Categorical Perception:
Even though speech sounds can blur together, we hear clear-cut categories—like hearing a sound as “b” or “p,” even if it’s somewhere in between.
(Similar to how we group shades of color into labels like “blue” or “green.”)
Phoneme Discrimination in Infants (Simplified):
At 6 months, babies can hear and tell apart all phonemes from any language in the world.
By 12 months, they get better at hearing sounds from their own language, but lose the ability to notice differences in unfamiliar ones.
This is called perceptual narrowing — their brain tunes in to what they hear most.
✨ In a way, 6-month-olds hear sound distinctions more accurately than adults!
Multimodal Integration in Infancy
Meltzoff & Borton (1979)
Newborns were given either a nubby or smooth pacifier to suck on (without seeing it).
Later, they were shown both pacifiers.
Babies looked longer at the one they had felt in their mouth, showing they could match touch with sight — even as newborns!
Lewkowicz & Ghazanfar (2009)
Newborns watched two monkeys vocalize.
When sound was added (a coo or grunt), babies looked more at the monkey whose mouth movements matched the sound.
This shows they can match sound and vision — an early form of multimodal integration.
🧠 But by the end of the first year, this ability narrows — infants become less sensitive to unfamiliar (non-native) face-voice pairings. This is perceptual narrowing again.
McGurk Effect
What we see can influence what we hear
Atkinson & Shiffrin Model of Memory
The mind processes information like this:
Sensory Memory:
Very brief storage of what we see or hear (half a second to a few seconds).
Encoding happens here—raw info comes in from senses.
Working Memory (Short-Term):
What we’re actively thinking about right now.
Holds info for about 15 seconds unless we keep repeating it.
Has limited space.
Storage here is temporary.
Long-Term Memory:
Stores info for a long time, with no known limit.
Includes facts (semantic), experiences (episodic), and skills (procedural).
Key Processes:
Encoding: How info gets into memory.
Storage: How info is kept.
Retrieval: How info is brought back when needed.
Attention: Decides which info from sensory or long-term memory is focused on and kept in working memory.
In short: Attention helps pick what info we focus on and keep active in our mind, so it can be processed and remembered.
Phonological Loop
A part of working memory that holds sounds for a short time.
It helps when you:
Talk with someone
Repeat a phone number to remember it
Read quietly by “saying” words in your head (sub-vocalization)
Think about a song’s tune
Visuospatial Sketchpad
A part of working memory that holds visual and spatial information for a short time.
It helps when you:
Use a map to find your way
Imagine turning an object in your mind (mental rotation)
Picture an image or someone’s face
Episodic Buffer
A temporary storage system that combines information from:
The phonological loop (sounds)
The visuospatial sketchpad (visual/spatial info)
Long-term memory
It helps you:
Remember past experiences
Imagine or plan new experiences (like a dancer thinking about music and movements
Central Executive
The “boss” or supervisor of working memory
Controls what information gets attention
Chooses how to solve problems or what strategies to use
Can only focus on one thing at a time because of limited capacity
Does not store information but manages and integrates it
Information Processing Theory
Compares the mind to a computer
Focuses on domain-general development (skills that apply across many tasks)
As children grow:
Processing speed increases
Working memory holds more info
More complex strategies can be used
Emphasizes the role of maturation in cognitive improvement
Autobiographical Memory
Childhood Amnesia:
Autobiographical Memory
Episodic memories of personal life events
Childhood Amnesia: Adults struggle to remember events from early childhood (before ~4 years)
Why Childhood Amnesia Happens? — 6 Proposed Factors
Why Childhood Amnesia Happens? — 6 Proposed Factors
Limited Working Memory
Young children can’t hold and organize complex event info
Working memory improves around age 4–5 (Bell & Wolfe, 2007)
Lack of Language
Language helps encode, store, and retrieve memories
Children recall only what they had words for at the time (Simcock & Hayne, 2002)
Sociocultural Support
Parents’ elaborative reminiscing (asking detailed questions) boosts memory
Children of elaborative parents recall earlier, richer memories (Jack et al., 2009)
Sense of Self
A developed self-concept helps link memories to the individual
Recognizing oneself (e.g., in a mirror) predicts better memory for past events
Verbatim vs. Gist Storage
Younger children store verbatim (exact) memories
With age, they shift to gist (general meaning), which are easier to retain (Brainerd & Reyna)
Neurogenesis
New neurons in infancy may “overwrite” early memories (Akers et al., 2014; in animals)
📚 Knowledge Base
Adults often outperform kids on memory tasks.
But not just due to bigger storage—adults have more knowledge/expertise.
Example: Chess
Chi (1978):
10-year-old chess experts remembered chess positions better than adult novices.
But adults remembered random numbers better.
Shows that expertise improves memory in specific domains.
🧩 Memory Strategies
Children develop strategies to boost memory:
- Rehearsal
Repeating info to remember it.
Digit Span Task shows:
Primacy effect (better recall of early items) is weaker in young children because they rehearse less.
- Chunking
Grouping info into meaningful units.
e.g., “747007409” → Jet (747), James Bond (007), Car (409)
Schneider (1986):
10-year-olds chunk better than 7-year-olds when given categorized pictures.
- Encoding / Maintenance
Storing info using:
Phonological loop (language/sounds)
Visuospatial sketchpad (images/space)
Episodic buffer (integrated memory)
🧪 Studies on Encoding/Storage Strategy Use
🗣️ Conrad (1971) – Phonological Loop Use
Children heard similar vs. different-sounding items.
After age 6, more errors with sound-alike items → shows use of phonological loop
Before age 6, performance was equal → likely using visuospatial sketchpad.
👁️ Hitch et al. (1988) – Visual vs. Verbal Confusability
5-year-olds: more trouble recalling visually similar items.
10-year-olds: more trouble with items that had long names.
Suggests younger kids use visual, older kids use verbal encoding.
🧠 Metamemory
🧠 Metamemory
Definition: Awareness of one’s own memory and how to manage it.
🌱 Young Children
Tend to overestimate memory ability.
May know strategies but not realize when to use them.
🧪 Wellman et al. (1975)
3-year-olds told to remember which cup hid a toy.
Many looked at/touched the correct cup while waiting → shows early metamemory behavior.
Those who used such strategies performed better.
✅ Key Takeaways
Memory improves in childhood due to:
More knowledge (expertise)
Use of strategies (rehearsal, chunking, encoding)
Switch to verbal memory systems with age
Development of metamemory—understanding and controlling memory
🧾 Children as Witnesses
Children are often asked to testify about real events (e.g., abuse cases, accidents).
Their memory reliability varies by age and context.
Young children are more vulnerable to false memories and suggestive questioning.
Key Issue: Source Monitoring
Definition: The ability to distinguish the origin of a memory.
Young children:
Confuse imagined vs. experienced events.
Are more suggestible due to immature source monitoring.
