Nondeclarative Memory

No conscious memory – but has effects on behavior.Priming is when presentation of one stimulus (the priming stimulus) affects the response to a stimulus that comes afterward (the test stimulus).

• Perceptual priming = priming stimulus leads to faster or more accurate processing of perceptual features.

• Conceptual priming = priming stimulus leads to faster or more accurate processing of meaning.

Perceptual Priming

Tulving (1982)– Show people 96 words (some are priming stimuli:

e.g., Toboggan )– People then quickly complete word fragment

puzzles• _O _O_GA _

– Compare performance on new words to performance on words used as priming stimuli

Word-Fragment Completion Task

Study List 1 Study List 2 "Test” List

elephant elevator e_e_h_n_ e_e_a_t_r market monkey m_r_e_ m_n_e_ doctor diamond d_c_o_ d_a_o_d closet clever c_o_e_ c_e_e_ ladder lover l_d_e_ l_v_r

Perceptual Priming

% of word fragment puzzles solved

Primed

New

Perceptual Priming

Tulving tried to prevent people from using declarative memory in the experiment

• Speeded test (no time for conscious awareness)• No memory test, instead people solved a problem

Tulving wanted to make sure that declarative memory (even very weak memory) was not causing repetition priming.

• Repeated the word-fragment study, and this time gave people recognition tests, too.

• Both tests were given at 1 hour and 7 days of delay

Performance

(good is up)

1 hour

7 days

Recognition Test

Word Fragment

Task

Over time:Performance on the recognition task decreased (DECLARATIVE) Performance on the word-fragment task the same (Nondeclarative)

Perceptual Processing with Degraded Pictures

Showing the intact picturespeeds later recognition of the degraded pictures.

Conceptual Priming

Lexical Decision TaskFast presentation of a word followed by a mask.Asked to decide if the next letter string is a word or not.

e.g., Butter as a prime leads to faster recognition of bread as a word.prime target reaction timedoctor nurse 500 ms chair nurse 525 ms

Skill Learning

e.g., Mirror Tracing or Inverted Text-Reading Skill learning is much more general and flexible than priming. Schwartz & Hashtroudi (1991) tested normal subjects for skill learning and priming and found no correlation between the two tasks.

Priming and Skill Learning depend on different mechanisms.

Amnesia

Caused by brain damage in which there are severe problems with long-term memory.Retrograde Amnesia – impaired memory for events occurring before the onset of amnesia.

Anterograde Amnesia – Reduced ability to form new memories after the onset of amnesia.(e.g., Clive Wearing).

Anterograde vs Retrograde Amnesia

Impaired memory for events after the trauma

Impaired memory for events before the trauma

Retrograde

Anterograde

Implicit Memory and Amnesia

Degraded Picture Test Elizabeth WarringtonAmnesias show impaired explicit memory but much less impairment of implicit memory.

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What remains Intact?

In general, Nondeclarative memory tasks do not differ between healthy participants and amnesiacs. Often have intact procedural memory!

Interesting ExampleTwo experienced drivers who developed severe amnesia due to bilateral hippocampal lesions participated in a series of standardized challenges of driving performance and knowledge of driving rules. During drives in a high fidelity simulator and on the road in an instrumented vehicle, they demonstrated vehicle control similar to that of normal drivers on measures of steering, speed control, safety errors, and driving with distraction. Their knowledge of driving rules, safety procedures, and road sign meaning also was normal. However, both participants were impaired at following route directions, and both had unsafe responses in a difficult crash avoidance scenario on the simulator. These findings suggest that memory impairment acquired by experienced drivers does not impair most aspects of driving performance, but may increase safety risk under some challenging circumstances. (Anderson et el., 2007)

Episodic Vs. Semantic MemoryAmnesiacs have impaired ability to form new episodic memories. Dewar et al. (2010) tested amnesiac episodic memory for a story under two conditions.Recall after 10 mins of doing a tone detection task.Recall after 10 mins in a dark quiet room.

Recall was much better in the second condition!Amnesiacs do form new episodic LTMs but they are very fragile and easily disrupted.

McCarthy et al. (2005) case study of RFR.Persistent severe anterograde and retrograde amnesia for personal and public events.

His personal semantic knowledge was relatively spared for the retrograde period (knew facts about himself).

Slight reduction in RFR's vocabulary for words acquired in adulthood before he became amnesic but not words learned in childhood.

Showed evidence of a limited but significant ability to acquire new word meanings and a restricted capacity for learning about new celebrities.

While he was able to demonstrate face and name familiarity for newly famous people (e.g., he could recognize and name Bill Clinton), he was unable to provide much semantic detail (did not know how or why he recognized Bill Clinton).

Case study shows impaired Semantic and Episodic memory.

Semantic vs. Episodic Memory

• While all anterograde amnesiacs have profound deficits in episodic memory, many have only minor (if any) semantic impairments:– Spiers, Maguire, & Burgess’s (2001) reviewed

147 cases.– Vargha-Khadem’s (1997) patients, Jon and

Beth (impaired as children but developed normal semantic memories).

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Vargha-Khadem’s (1997)

Global anterograde amnesia is described in three patients with brain injuries that occurred in one case at birth, in another by age 4, and in the third at age 9. MRIs showed bilateral hippocampal damage in all three cases. Remarkably, despite their pronounced amnesia for the episodes of everyday life, all three patients attended mainstream schools and attained levels of speech and language competence, literacy, and factual knowledge that are within the low average to average range.

Vargha-Khadem’s patients give us Neurological Evidence of Dissociation!

Episodic Memory depends highly on the hippocampus!

Semantic Memory relies on areas adjacent to the hippocampus. Problem: Brain damage sufficient to impair episodic memory will typically also impair semantic memory.

An Alternative Explanation

• Ryan et al. (2000) Relational memory binding– Amnesiacs have difficulty forming associations

between two concepts or pieces of information.

How will amnesiacs do on a procedural task that involves forming associations?According to the traditional (Explicit vs. Implicit) view they should do well, if the need to make associations among objects impairs the task it suggests the problem is with binding information.

Procedure

Stimuli – color images of real world scenes.Three conditions:1. Novel scenes2. Repeated old scenes3. Manipulated – repeats but with positions of objects

altered.Procedural implicit task measure - Measured the proportion of time the eye fixations were in the critical area of scene (manipulated).

Healthy Controls – showed increased eye fixation in critical areas of manipulated scenes indicating implicit memory for the relationship between the objects.

Amnesiacs – showed no increased eye movements (i.e., lack implicit memory for the original scene).

Explicit task where no associations are needed

Huppert and Piercy (1976): On Day 1 of the experiment, subjects were shown 80 photographs Half of the photographs were presented to subjects once, and the other half were presented three times. On Day 2 of the experiment, another 80 photographs were presented, half once and half three times. The test phase occurred on Day 2, and subjects were asked to indicate whether each of a long list of photographs was seen on Day 1 or 2, and whether it was presented once or three times when it was studied.

The critical data come from the conditions in which a photograph was presented three times on Day 1, or once on Day 2.

Control subjects tended to judge accurately the day and frequency of presentation of these items. However, amnesics tended to judge Day 1 items presented three times as having been presented on Day 2.

Similarly, they tended to judge Day 2 items presented once as having been presented three times. These data indicate that amnesiacs were responding on the basis of an item's familiarity, whereas controls tended to respond on the basis of the context in which an item was presented.

In other words, a photograph shown three times on Day 1 is often judged to have been shown on Day 2 by the amnesic because its familiarity may be similar to many of the photographs shown once on Day 2.

On the other hand, a photograph shown three times to a control subject would give that subject three opportunities to bind the presentation of that photograph to the context (Day 1).

Also remember

Skinner & Fernandes (2007) – amnesiacs with hippocampus damage show impaired recollection compared to controls, but comparable familiarity judgments.

Double Dissociation - Capgras’ Syndrome

Forgetting From Implicit Memory

Mitchell (2006) - Fragmented Picture test 17 years after the original presentation!!Significant Implicit memory but little if any explicit memory of having been in the original study.

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Encoding Specificity PrincipleGetting Information back out depends on the appropriateness of the cues at recall.

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Context Effects

Recall memory is better when tested in the same environment that the material was learned in.

The same is not true for recognition.

WHY?

Figure 5.10 Words learned and tested in the same environment are better recalled than those items for which the environmental context varied between study and test. Data from Godden and Baddeley (1975).

Context Can be External or Internal

Miles and Hardman (1998) - Cardiovascular rate.

Marian and Kaushanskayu (2007) language –dependency effect.

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State Dependent Memory

• Same effect for alcohol.

Mood Dependent Memory- generally recall pleasant better than unpleasantPollyanna Principle

- better encoding- more rehearsal- available

Depression and Memory

Recognition vs. Recall

Recognition is generally better but . . . if the cues at recall are better than recognition cues – recall should be better. (Muter, 1978)

Circle the last names of famous people.~ 29% correct!

Author of Last of the Mohicans: James Fennimore ___________.~ 42% correct!

Proactive and Retroactive InterferenceSimilar items learned earlier (proactive) or after (retroactive) interfere.

Why? Similar cues lead to a variety of items in LTM.When a memory from anearlier or later time is stronger(e.g., more distinctive) it is Likely to interfere.

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Memory Consolidation

Why is the rate of forgetting greatest shortly after learning?

Figure 5.9 Forgetting over time as indexed by reduced savings during relearning. Data from Ebbinghaus (1885/1913).

Memory Consolidation

A process after initial encoding that is critical to stable long-term memory

Stabilizes memories.Incorporates new information with old.

Two Phases

1st Phase: Cellular or synaptic consolidation• Brief process over a period of hours• Involves Hippocampus

2nd Phase: Systems consolidation• Lasts weeks, months, or years• Applies only to semantic and episodic memory• Involves interactions between the hippocampus

and the neocortex.

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Your memory for last new year’s Eve could include sights, sounds, smells, emotions you were feeling and thoughts you were thinking at the stroke of midnight

Experience results in activity of the different cortical areas

No connection in the cortex

Graded amnesia – Retrograde amnesia is most severe for events that occurred just prior to the injury and becomes less severe for earlier, more remote events

Alcohol and Memory Consolidation

• Alcoholic amnesia – alcohol prevents consolidation so nothing is remembered and no memory can be recovered.

• Alcoholic blackout – state- dependent memory, so recall is possible if one is back in the same state.

REM Sleep and Memory Consolidation

Memory consolidation is associated with REM periods of sleep.

e.g., Significant increase in post-training REM sleep after intensive foreign language learning, with the degree of successful learning correlating with the percentage increase of REM sleep.

Misremembering

Reconsolidation – reactivation of a memory trace that has already been consolidated puts it back in a fragile state – allowing it to be updated and altered.

• Walker et al. (2003)Day One:Participants learned a finger tapping routine.Day Two:Learned a different finger tapping routine.2 conditions – Brief rehearsal of day one routine or not.

Then retested on Day one routine.Brief rehearsal condition was worse.

WHY?

Rehearsal re-activated the previously learned routine making it’s memory trace more fragile!

Hindsight Bias

Tendency to exaggerate how accurately a person would have predicted some event in advance after they know what actually happened.

Knew it all along effect.Might be due to reconsolidation.

Post-Event Misinformation Effect

Loftus & Zanni (1975)Did you see the broken Headlight?

“