Spanos, N.P., Burgess, C.A., Burgess, M.F., Samuels, C. & Blois, W.O. (1999). Creating false memories of infancy with hypnotic and non-hypnotic procedures. Applied Cognitive Psychology, 13, 201-218.

Goal: study designed to make participants generate memories from the day after their birth. This day was chosen because all available data suggest that adult recall of episodic memories from that time is impossible.

Background stuff: research suggests that false memory generation is facilitated in clinical settings by regression procedures that provide the patient with an expectation that they have been abused (current symptoms), encourage them to generate consistent ideas (dreams), and legitimate these imaginings as actual memories.

Purpose and rationale: lots of evidence suggests that complex and detailed false memories of really traumatic experiences can be elicited during some kinds of psychotherapy. Consequently the recovered memory debate should not be about whether false memories are generated in clinical contexts (as opposed to only experimental settings), but rather about the conditions that facilitate the generation of these memories. There is no reason to assume that the conditions differ in experimental and clinical settings.

So they designed this study to compare the effects of hypnotic and non-hypnotic procedures in leading undergraduates to produce memories of infancy. Since both groups were given extensive rationales concerning why their regression procedure was likely to facilitate retrieval of such memories from an authoritative source, they hypothesized that these groups would report false memories to a similar degree.

Method: 117 general psychology students (41 males and 76 females) were pre-tested for hypnotizability and divided into high (n = 39), medium (39), and low groups (39). Within these levels, they were randomly assigned to 3 treatment conditions: hypnotic regression (13), non-hypnotic regression (13), and a control (13).

The two experimental groups completed a fantasy proneness inventory, the DES, a temporal lobe lability scale, and a paranormal belief and liberal belief subscales of the PPI.

The completed questionnaires were taken into another room and "computer analyzed". A "personality profile" was generated (same one given to each person), which classified them as "High Positive Cognitive Monitors". They were informed that this insightful, intuitive cognitive style was largely determined by "practice at coordinated eye movements and visual exploration that occurred during a critical period during the first few days after birth." They were also told that they were probably born in hospitals that hung colored mobiles over their cribs shortly after birth.

Hypnotic regression treatment: they were told that the purpose of the procedure was to confirm that they had been born in hospitals that hung mobiles over their cribs. Further, they were told that the hypnosis was an effective way of retrieving such memories and that they would be "taken back" to that event. There was a five-minute orally given hypnotic induction procedure during which they were asked to recall increasingly earlier information (that most people can easily recall). Lastly, they were asked to recall the day after birth and specifically to look above their heads and describe what they saw. Additionally, there was a request to change to the by-stander perspective and view themselves from the "outside". These sessions were audio taped and coded for whether or not infancy memories were generated and for the presence or absence of the mobile.

After being returned to their adult selves, they completed a series of Likert scales: the extent to which they believed the infancy experiences were real memories, the degree to which the adult self faded into the background, their absorption in the infancy experience, and the vividness of the infancy experience.

They were scheduled for sessions a week later. Before they left, they were told that the experience may trigger unbiblical itchiness and thoughts or dreams about infancy. When they returned, they rated their belief in the infancy experience, assessed the frequency with which they experienced umbilical itching, and direct and indirect thoughts and dreams of infancy.

Non-hypnotic regression treatment: same procedure, except they were told that hypnosis only works for some people, so they were going to experience a technique that worked for everyone, "guided mnemonic restructuring". They were then given non-hypnotic suggestions like, "really try your best to recreate the situation in your mind".

Control treatment: they only came in for one session, during which they received no memory enhancing procedures. They just completed the questionnaires and assessed the frequency with which they experienced unbiblical itching, thoughts, or dreams about infancy in the previous week. Finally they were asked to "think back" to being in a crib the day after their birth and assess the extent to which they felt that was a real memory.

Results:

False memory reports: 1) the non-hypnotic group was more likely to report regression memories than the hypnotic group (95% vs. 79%). 2) High and medium hypnotiz-ables were combined into one group (cell size problem) and compared to the low group. There was no significant difference, indicating that all three groups were equally likely to report false memories (low-51%, medium-59%, and high-64%).

Mobile reports: 1) hypnotic and non-hypnotic groups did not differ in mobile recall (hypnotic-46% and non-hypnotic-56%). 2) Mediums and highs were more likely than lows to incorporate the mobile into their memory (high-62%, medium-62%, low 31%).

Belief in the infancy experience: 1) no difference between first and second sessions, so only belief ratings from session 2 are used in analyses. 2) hypnotic and non-hypnotic participants reported stronger beliefs in the reality of their experience than did the controls. See table 1.

Intensity of the infancy experience: 1) hypnozability had a significant effect on reported degree of adult fading, absorption, and vividness. 2) mediums and highs didn't differ from each other, but these groups reported a greater degree of adult fading, absorption, and vividness than the low hypnotiz-ables.

Thoughts: 1) hypnotic and non-hypnotic highs did not differ in their ratings of thoughts about infancy, but reported more frequent thoughts than did highs in the control treatment. 2) hypnotic highs and mediums reported significantly more frequent thoughts than did hypnotic lows. 3) no significant difference was found between highs, lows, and mediums in the non-hypnotic group. 4) mediums in the control condition reported more thoughts than did highs and lows (no difference) in the control condition.

Dreams: 1) participants were categorized as having experienced no dreams about infancy in the previous week (0) or as experiencing at least one dream in the previous week (1). 2) they compared the two experimental groups to the control group and found a significant difference, 50% of the age-regressed subjects experienced direct dreams of infancy , while only 21% of the controls experienced these dreams during the previous week. 3) results were similar for the symbolic dreams: 31% of experimentals and 8% of controls.

Body memories: 1) again, participants were categorized as either 0 or 1. 2) there was no significant difference in belly button itching between the three groups: hypnotic group-31%, non-hypnotic group-33%, and control group-38%.

Correlations: 1) the memory report index (1 or 0) correlated significantly with objective and subjective dimensions of the levels of hypnotizabilty scale (CURSS), fantasy proneness, and temporal lobe lability. 2) all correlations between the dimensions of the hypnotizability scale and the fantasy proneness, temporal lobe lability, and DES scores were significant (DES did not correlate with false memory reporting). 3) hypnotizability also correlated with ratings of adult fading during regression, absorption in the infancy experience, and vividness of the experience.

Discussion: 1) some experiences like thoughts and dreams may be reported simply because they have been suggested by a significant other. Therefore, the idea of these occurrences becomes highly salient. 2) merely inquiring about physical sensations and symptoms is associated with a high probability of eliciting an affirmative response. 3) although it is unknown what role compliance plays in studies like these, this effect may also be prevalent in clinical settings. 4) this study suggests that many individuals will report false memories when they are provided with a rationale from an authoritative source that makes the occurrence of such memories plausible, when they are provided with information that leads them to expect that they possess such memories, and when they are administered procedures that they believe will facilitate the recovery of hidden memories.


University of Arkansas

Department of Psychology

Lampinen Lab

False Memory Reading Group

False Memory Reading Group Summer 2000