Trauma victims with post-traumatic stress disorder (PTSD) often experience ‘flashbacks’ that are described as being different from memories of other fearful biographic situations. We used Positron Emission Tomography and Statistical Parametric Mapping to compare in the same subject brain activation patterns during induced flashbacks with recall of fearful non-traumatic situations. During fearful recall there were significant activations of right precuneus. When traumatic memories were compared to neutral, right lingual gyrus, right thalamus / mamillary bodies, and right cerebellum were significantly activated. When brain activation during flashbacks was compared to simple fear, right mediodorsal thalamus (MD), right precuneus, and right cerebellum were significantly more active. With respect to recent experimental evidence concerning the function of thalamo-cortical systems, we hypothesize that post-traumatic flashback experiences are based on hyperactive thalamo-cortical ‘closed loop’ networks.
Andreasen, NC, O'Leary, DS, Cizadlo, T, Arndt, S, Rezai, K, Watkins, GLet al (1995): Remembering the past: two facets of episodic memory explored with positron emission tomography. American Journal of Psychiatry152: 1576-1585.
2.
Andreasen, NC, O'Leary, DS, Paradiso, S, Cizadlo, T, Arndt, S, Watkins, GLet al (1999): The cerebellum plays a role in conscious episodic memory retrieval. Human Brain Mapping8: 226-234.
3.
Armstrong, E (1990): Limbic Thalamus: Anterior and Mediodorsal Nuclei. In Paxinos, G, editor. The Human Nervous System. Los Angeles: Academic Press, pp 469-480.
4.
Bremner, JD, Southwick, SM, Charney, DS (1999): The neurobiology of posttraumatic stress disorder: an integration of animal and human research. In Saigh, P, Bremner, JD, Neddham Heights, MA, editors. Postraumatic Stress Disorder: a Comprehensive Text: Allyn & Bacon, pp 103-143.
5.
Bremner, JD, Staib, LH, Kaloupek, D, Southwick, SM, Soufer, R, Charney, DS (1999): Neural correlates of exposure to traumatic pictures and sound in Vietnam combat veterans with and without posttraumatic stress disorder: a positron emission tomography study. Biological Psychiatry45: 806-816.
6.
Creutzfeldt, OD (1983): Cortex cerebri. New York Heidelberg Berlin: Springer.
Friston KJ, HAWKPJFCFR. Statistical Parametric Maps in Functional Imaging: A General Linear Approach. Human Brain Mapping2, 189-210. 2000. Ref Type: Generic
9.
Friston, KJ, Holmes, A, Poline, JB, Price, CJ, Frith, CD (1996): Detecting activations in PET and fMRI: levels of inference and power. Neuroimage4: 223-235.
10.
Horowitz, M, Wilner, N, Alvarez, W (1979): Impact of Event Scale: a measure of subjective stress. Psychosomatic Medicine41: 209-218.
11.
Jones, EG (1981): Functional subdivision and synaptic organization of the mammalian thalamus. International Review of Physiology25: 173-245.
12.
Kapur, N, Friston, KJ, Young, A, Frith, CD, Frackowiak, RS (1995): Activation of human hippocampal formation during memory for faces: a PET study. Cortex31: 99-108.
13.
Krause, BJ, Schmidt, D, Mottaghy, FM, Taylor, J, Halsband, U, Herzog, Het al (1999): Episodic retrieval activates the precuneus irrespective of the imagery content of word pair associates. A PET study. Brain122: 255-263.
14.
Krettek, JE, Price, JL (1977): The cortical projections of the mediodorsal nucleus and adjacent thalamic nuclei in the rat. Journal of Comparative Neurology171: 157-191.
15.
Lang, PJ (1985): The cognitive psychophysiology of emotion: Fear and anxiety. In Tuma, A, Maser, J, editors. Anxiety and the anxiety disorders. Hillsdale, NJ: Erlbaum, pp 131-170.
16.
Lang, PJ, Bradley, MM, Fitzsimmons, JR, Cuthbert, BN, Scott, JDet al (1998): Emotional arousal and activation of the visual cortex: an fMRI analysis. Psychophysiology35: 199-210.
17.
Llinas, RR, Ribary, U (1994): Perception as an Oneiric Like State Modulated by the Senses. In Koch, C, Davis, JL, editors. Large-Scale Neuronal Theories of the Brain. Cambridge, Massachusetts: Bradford Book, MIT Press, pp 111-124.
18.
Maercker, A and Schützwohl, M.Erfassung von psychischen Belastungsfolgen: Die Impact of Event Skala-revidierte Version (IES-R). Diagnostica44, 130-141. 1998. Ref Type: Generic
19.
Pitman, RK, Orr, SP (1995): Psychphysiology of emotional memory networks in posttraumatic stress disorder. In McGaugh, JL, Weinberger, NM, Lynch, G, editors. Brain and memory. New York Oxford: Oxford University Press, pp 75-83.
20.
Quarles, RP, Mintun, MA, Larson, KB, Markham, J, MacLeod, AM, Raichle, ME (1993): Measurement of regional cerebral blood flow with positron emission tomography: a comparison of [15O]water to [11C]butanol with distributed-parameter and compartmental models. Journal of Cerebral Blood Flow & Metabolism13: 733-747.
21.
Rauch, SL, Savage, CR, Alpert, NM, Miguel, EC, Baer, L, Breiter, HCet al (1995): A positron emission tomographic study of simple phobic symptom provocation. Archives of General Psychiatry52: 20-28.
22.
Rauch, SL, van der Kolk, BA, Fisler, RE, Alpert, NM, Orr, SP, Savage, CRet al (1996): A symptom provocation study of posttraumatic stress disorder using positron emission tomography and script-driven imagery. Arch.Gen.Psychiatry53: 380-387.
23.
Scheibel, AB (1997): The Thalamus and Neuropsychiatric Illness. In Salloway, S, Malloy, P, Cummings, JL, editors. The Neuropsychiatry of Limbic and Subcortical Disorders. Washington, DC: American Psychiatric Press, pp 31-42.
24.
Shapiro, F (1996): Eye movement desensitization and reprocessing (EMDR): evaluation of controlled PTSD research. [Review] [36 refs]. Journal of Behavior Therapy & Experimental Psychiatry27: 209-218.
25.
Shin, LM, McNally, RJ, Kosslyn, SM, Thompson, WL, Rauch, SL, Alpert, NMet al (1999): Regional cerebral blood flow during script-driven imagery in childhood sexual abuse-related PTSD: A PET investigation. Am.J.Psychiatry156: 575-584.
26.
Shook, BL, Schlag-Rey, M, Schlag, J (1991): Primate supplementary eye field. II. Comparative aspects of connections with the thalamus, corpus striatum, and related forebrain nuclei. Journal of Comparative Neurology307: 562-583.
27.
Talairach J, Tournoux P (1988): Co-Planar Sterotaxic Atlas of the Human Brain. New York: Thieme Medical Publishers.
28.
Watson, D, Clark, LA, Tellegen, A (1988): Development and validation of brief measures of positive and negative affect: the PANAS scales. Journal of Personality & Social Psychology54: 1063-1070.
29.
Wienhard, K, Dahlbom, M, Eriksson, L, Michel, C, Bruckbauer, Tet al (1994): The ECAT EXACT HR: performance of a new high resolution positron scanner. Journal of Computer Assisted Tomography18: 110-118.
30.
Zilberg, NJ, Weiss, DS, Horowitz, MJ (1982): Impact of Event Scale: a cross-validation study and some empirical evidence supporting a conceptual model of stress response syndromes. Journal of Consulting & Clinical Psychology50: 407-414.
