Docstoc

ISPNE_jahn_2006

Document Sample
ISPNE_jahn_2006 Powered By Docstoc
					                               The relationship between cortisol and memory: Preliminary analysis on the
                                                                                           role of affective state and the amygdala
                                                                     Allison L. Jahna,b, Simone Kernb, Richard J. Davidsona, b, Jerry L. Halversona,
                                                                                                 Clemens Kirschbaumc, and Heather C. Abercrombiea
       University of Wisconsin-Madison Departments of Psychology & Psychiatrya, The Waisman Laboratory for Brain Imaging and Behavior b, Technical University
                                                                          of Dresdenc
Background                                  Methods                                        RESULTS                                                      *                                                                                                                                                                                                      0.57
                                                                                                                                                      Counterbalanced
                                                                                                                                                                                                                                                                                                                                                                                                                                           0.52
Historically, cortisol has been considered harmful to cognition and health.
However, animal and human data suggest that moderate cortisol elevations can
                                                                                                                                                  15 mg
                                                                                                                                                  Cortisol         Placebo
                                                                                                                                                                                                        Memory Data for Low & High PA                                                                                                                          0.52

                                                                                                                                                                                                                                                                                                                                                                                                                                           0.47
be beneficial.
                                                                                                                                                                                                                                                                                                                                                               0.47
                                                                                                                                                                                                                                                                                                                                                                                                               Low PA
Cortisol release affects cognitive processes such as memory. Research is divided                                                                                                                                                                                                                                                                                                                                                                                                          Low PA




                                                                                                                                                                                                                                                                                                                                                          Pr




                                                                                                                                                                                                                                                                                                                                                                                                                                      Pr
                                                                                                                                                                                                                                                                                                                                                                                                               High PA                                                                    High PA
                                                                                                                                                                                                                                                                                                                                                                                                                                           0.42
with some studies finding that cortisol impairs memory and others finding that                                                                                                                                                                                                                                                                                 0.42

cortisol facilitates memory (Maheu et al. 2004; Abercrombie et al. 2003).                                     Screening Visit   MRI Sim ulation
                                                                                                                                                                                  Memory Test
Interestingly, research suggests that the beneficial effects of cortisol on memory                                                                                                                                                                                                                                                                             0.37                                                                        0.37
                                                                                               Phone Screen                                            Beginning
depend on the emotional state of the individual (Okuda et al., 2004; Abercrombie                                                                     approx. 4:30pm
et al., 2006). These studies suggest that state negative affect plays a permissive                                                                                                                                                                                                                                                                             0.32
                                                                                                                                                                                                                                                                                                                                                                                                                                           0.32

role in the effects of cortisol on memory.                                                                                                          3.0 T esla GE SIGNA
                                                                                                                                                                                                        Amygdala ROI for Low & High PA                                                                                                                                    Placebo        Cortisol
                                                                                                                                                                                                                                                                                                                                                                                                                                                             Placebo    Cortisol

                                                                                                                                                           Scanner                                                                                                                                                                                                                                                                             *Significance p < 0.05
Animal data suggests that amygdala activation, specifically the basolateral region                                                                                                                      Contrast:                                                                                                                                                                                                                              Interaction: F (1,12) = 6.16, p <
of the amygdala, is necessary for the beneficial effects of cortisol on memory. To                                                                                                                                                                                                                                                                                                                                                             0.05
date, this is the first human investigation of the role of the amygdala in the effects                                                   FMRI Stimuli Presentation                                      Negative Word Trials – (Neutral + Positive Word Trials)
of cortisol on memory.                                                                                                                                                                                                                                                                                                                   Average Percent Signal Change
Hypotheses: We hypothesize that a moderate dose of cortisol given in the late                                                                                                                                                                                                                                                                 Left Ventral Amygdala
                                                                                                                                                       quiet                                                                                                                                                                                                                                                             Time Course Left Ventral Amygdala
afternoon (when endogenous levels are low) will be related to increases in brain                                                                                                                                                                                                                                                  1.6                 †
activation in the amygdala compared to placebo. We hypothesize that this effect                                                                                    +
                                                                                                                                                                                                                      R                                               L                                                           1.4
                                                                                                                                                                                                                                                                                                                                                                                                          25


will be associated with emotional state. Finally, we hypothesize that changes in                                                                                                                                                                                                                                                  1.2                                                                     20

emotional state will be related to changes in memory for words encoded during




                                                                                                                                                                                                                                                                                                          Percent Signal Change
                                                                                                                                                                             lonely                                                                                                                                                 1                                                                     15
elevated cortisol.
                                                                                         • AVOTEC goggle system & Eprime                                                                                                                                                                                                          0.8                                               Low PA                10                                                                       LowPA Cort Ng
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   LowPA Plac Ng
                                                                                         Presentation Software for stimuli display                                                    +                                                                                                                                           0.6                                               High PA                                                                                        LowPA Cort NuPo
                                                                                                                                                                                                                                                                                                                                                                                                           5
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   LowPA Plac NuPo


Participants                                                                             • SRET (Self-Referent Encoding Task) participants                                                                                                                                                                                        0.4
                                                                                                                                                                                                                                                                                                                                                                                                           0

                                                                                         asked to decide whether descriptive words are                                                    exhilarated                                                                                                                             0.2
• Data collection is ongoing                                                             self-referent by making a dichotomous button press.                                                                                                                                                                                        0
                                                                                                                                                                                                                                                                                                                                                                                                          -5



                                                                                         Each scan has different sets of words matched                                                                                                                                                                                                                                                                   -10
• 17 Participants (5 Women; Age-M:28.72; SD:7.21; 3 participants dropped from                                                                                                                                                                                                                                                     -0.2                                                                              0          2           4             6         8   10
                                                                                         for valence and arousal.                                                                                                                                                                                                                           Placebo            Cortisol       † Trend p < 1.0                                                  Seconds
analysis; 1 for abnormal levels of cortisol on the cortisol scan day; 1 experimenter
error; 1 abnormal memory values on the memory testing day)                               • Memory session: recognition memory assessed 4-6 days
                                                                                         after scanning session
• Right handed; Free of general health issues; Free of psychiatric disorders
                                                                                                                                                                                                          Conclusion
                                                                                                                                                                                                          While these analyses are preliminary, we find support for increased brain activation in the ventral amygdala after the
                                                                                                                                                                                                          administration of cortisol only in individuals with low positive affect. This effect was found in response to negative words
MRI Methods & Analysis                                                                                                                                                                                    compared to neutral and positive. Also, we find that individuals with low positive affect also show greater memory for words
Quadrature Birdcage Coil for T1 high resolution anatomical & BOLD
                                                                                           Group Selection                                                                                                encoded during cortisol administration – and that this effect is more evident when examining memory for negatively valenced
                                                                                           Positive and Negative Affect Schedule (Watson, Clark, & Tellegen, 1988)                                        words.
Sagital Acquisition; Flip Angle: 90 degrees; TR: 2000 ms; TE: 30 ms
                                                                                                      •Due to low variation in negative affect scores we used positive affect                             Future directions: We hypothesize that cortisol will alter brain activation in other regions such as the hippocampus,
Slices per Volume: 30; Voxel Size: 3.75 x 3.75x 4mm with 1 mm gap                                                                                                                                         parahippocampal gyrus, and prefrontal cortex. Activation in these regions may be especially important because of their
                                                                                                      as an index of affective state
AFNI: Slice timing correction, Motion correction, Spatial smoothing: 6mm                                                                                                                                  association with memory and emotion. We are also collecting data on emotion and arousal ratings of the stimuli in the
                                                                                                      •Median split: 7 Low Positive Affect (Low PA; 3 women); 7 High                                      scanner. Thus, we will examine the relationship among memory, changes in brain activation, and affective responses.
Normalization to Talairach space                                                                      Positive Affect (High PA; 2 women)
Extraction of amygdala ROI in AFNI with predefined masks
                                                                                                                                                                                                        References:
                                                                                                                                                                                                        Abercrombie HC, Kalin NH, Thurow ME, Rosenkranz MA, Davidson RJ (2003). Cortisol variation in humans affects memory for emotionally laden and neutral information. Beh Neuroscience 117:505-16.
GLM: Gamma Variate Function; percent signal change from baseline for Negative                                                                                                                           Abercrombie, H.C., Speck, N.S., & Monticelli, R.M. (2006). Endogenouscortisol elevations are related to memory facilitation o nly inindividuals who are emotionally aroused. PNEC 31:187-96.
                                                                                                                                                                                                        Maheu FS, Joober R., Beaulieu S, Lupien SJ (2004). Differential Effects of Adrenergic and Corticosteroid Hormonal Systems on Human Short- and Long-Term Declarative Memory for Emotionally Arousing Material. Beh Neuroscience 118:420-8.
Word Trials – (Neutral + Positive Word Trials)                                                                                                                                                          Okuda S, Roozendaal B, McGaugh JL (2004). Glucocorticid effects on object recognition memory require training -associated emotional arousal. PNAS 101:853-8.
                                                                                                                                                                                                        Watson D, Clark LA, Tellegen A (1988). Development and Validation of Brief Measures of Positive and Negative Affect: The PANA S Scales. J Personality & Social Psych 54:1063-70.


                                                                                                                                                                                                        This research was supported in part by a NARSAD Young Investigator Award given to Heather Abercrombie.

				
DOCUMENT INFO
Shared By:
Categories:
Stats:
views:4
posted:7/10/2011
language:English
pages:1