Prenatal and perinatal psychology

Last updated April 22, 2024

Prenatal psychology can be seen as a part of developmental psychology, although historically it was developed in the heterogenous field of psychoanalysis. Its scope is the description and explanation of experience and behaviour of the individual before birth and postnatal consequences as well. In so far as the actual birth process is involved one can consider this perinatal psychology. Pre- and perinatal aspects are often discussed together.^[1]

Prenatal and perinatal psychology explores the psychological and psychophysiological effects and implications of the earliest experiences of the individual, before birth (prenatal), as well as during and immediately after childbirth (perinatal). Although there are various perspectives on the topic, a common thread is the importance of prenatal and perinatal experiences in the shaping the future psychological development. There is a debate among scientists regarding the extent to which newborn infants are capable of forming memories, the effects of any such memories on their personality, and the possibility of recovering them from an unconscious mind, which itself is the subject of argument in the field. A widespread assumption concerning the prenatal phase was that the fetus is almost completely shielded from outside stimuli. Thus, perception and consciousness would develop after birth. Meanwhile, there is a great number of scientific studies which show clearly that behaviour, perception and learning is already developed before birth. This also holds for nonhuman species, as for rat fetuses acoustic conditioning can be demonstrated.^[2]

Psycho-physiological aspects of the prenatal phase

Fetus, connected with the mother by umbilical cord and placenta Placenta.svg — Fetus, connected with the mother by umbilical cord and placenta

The physiological development while in the prenatal phase – especially that of the brain – is of particular importance for prenatal psychology. In the first eight weeks after insemination, the developing child is called an embryo. After the inner organs have developed (from the ninth week on) it is called a fetus.

Prenatal development of the brain

The basis of perception, experience, and behaviour is the brain. While in gestation, a giant neuronal net is developing, delivering the condition for any mental process. About half of the developing neurons become destroyed again during the development of the brain because of the "programmed cell death" (apoptosis). At birth the infantile brain contains 100 billion neurons – as many as in the brain of an adult.^[3] At birth, every cortical neuron is connected with about 2500 neurons; after a year, with about 15 000.^[4] Synapses develop, and are destroyed, over the whole life span – a process called neuroplasticity.

Motor development

In the 1930s the physiologist Davenport Hooker examined reflexes or reactions, respectively of aborted fetuses extrauterine.^[5] Nowadays, the motor skills of embryo and fetus can be examined with ultrasound techniques quite easily. From the eighth week on the embryo moves the rump, shortly after that his extremities.^[6] With the means of sonography one could demonstrate that these were not simple reflexes, but also endogenously provoked movements.^[7] According to Alessandra Piontelli the fetus shows all patterns of movement, which later can be found in the newborn.

Breath movements can be seen from the 19th week on, with the fetus taking amniotic fluid into his lungs.^[8] Eye movements are shown to exist from the 18th week on, from the 23rd week on there are rapid-eye-movements (REM-phases).^[9] These are connected with sleeping patterns and dreaming. Fetuses drink amniotic fluid and urinate into it.^[10]

Development of perception and prenatal learning

The sense modalities of the fetus develop prenatally and are functioning very well at birth. The examination of such abilities is connected with experimental examination of behaviour, provoked by stimuli. Ray examined vibro-acoustic conditioning of human fetuses. According to Hepper it rested uncertain, if such conditioning was successful.^[11] Hepper claims to have repeat such conditioning experiments successfully, with the earliest vibro-acoustic conditioning in the 32nd week of gestation.^[12]

Prenatal learning often is examined by using the habituation paradigm.^[13] The fetus gets exposed to a stimulus, e.g. an acoustic one. Afterwards the experimenter watches the extinction of the reaction while repeating the same stimulus again and again. This procedure becomes completed by the use of a new stimulus and the recording of the according reaction. When the new stimulus is identified by the fetus as different from the old one, it releases a new pattern of reaction, e.g. accelerated frequency of the heart. If this does not happen, the new stimulus cannot be distinguished from the old focal stimulus. In 1991 a study demonstrated the acoustic habituation by recording the heart frequency of foetuses in the 29th week of gestation.^[14] Such studies can be used for examining memory. Fetuses older than 34 weeks of gestation can reproduce learned content over a period of 4 weeks.^[15] The earliest vibro-acoustic conditioning is successful at 22-week-old fetuses.^[16] Maybe habituation to taste is possible even earlier.^[17] Such habituation was also demonstrated in fetal rats.^[18]

Babies remember musical patterns they once heard in the womb, as W. Ernest Freud – a grandson of Sigmund Freud – could demonstrate.^[19] The empirical proof used the registration of heart frequency and motorical activity.^[20]

Also the development of speech is based on prenatal learning, as the study of DeCasper and Fifer from 1980 seems to demonstrate.^[21] This study used operant conditioning as a paradigm. Several empirical studies demonstrated that prenatal learning exists.^[22]

Historical development of psychoanalytical and depth psychological theories concerning prenatal life

Most psychoanalytical theories assume that the development of objects, the self and even consciousness begins after birth. Nevertheless, some psychoanalysts explicitly write that pre- and perinatal aspects are responsible for certain symptom formations, among them Otto Rank, Nandor Fodor, Francis J. Mott, Donald Winnicott, Gustav Hans Graber and Ludwig Janus. They think that the structuring of the unconscious psyche starts in the prenatal phase. The fetus already has early, emotionally relevant experiences. They assume the existence of perception in several sense modaliaties, states of asphyxia, fears and stress, which are stored and can be remembered after birth under certain circumstances. In psychoanalysis pre- and perinatal topics usually are seen as fantasies. The manifest prenatal content of dreaming or fantasizing of swimming under water while breathing, being inside of a cave, fighting with underwater monsters – are interpreted as re-projections in time onto the early phase.^[23] Janus assumes that in many psychoanalytical approaches there can be found contentual and phenomenological aspects close to prenatal psychology – but without explicit references. Janus wrote of the "hidden attendance of the prenatal existence" in the works of psychoanalysts such as Sandor Ferenczi, Carl Gustav Jung, Melanie Klein, Bela Grunberger, Françoise Dolto and others.^[24]

In 1924 Otto Rank (1884–1939), one of Sigmund Freud's disciples, published his book The Trauma of Birth (German: Das Trauma der Geburt und seine Bedeutung für die Psychoanalyse). There he stated that the emotional shock of being born is an individual's first source of anxiety. Because of this book the friendship between Freud and Rank came to an end.^[25] Rank was of the opinion that birth is connected with an overwhelming experience of fear of the fetus. He also presumed that this trauma was the cause of later anxieties. He also claimed that aspects of the later prenatal phase can be remembered.^[26] So already Rank himself had developed the outlines of a true prenatal psychology. In the light of such assumptions he interpreted cultural aspects, e.g. he understood Christian fantasies of the hell as being based on aversive intrauterine situations.^[27] In his book, he treated the interpretation of symbols, art and myths by using pre- and perinatal assumptions. Rank believed that a "primal fixation" with the prenatal state is the root of all neuroses and character disorders^[28] and developed a process of psychoanalysis based on birth experiences.^[29]^[30]

Donald Winnicott (1896–1971) tried to understand very early forms of symbol formation. He described in several case studies the reenactment of perinatal experiences in psychotherapies, especially of children. A five-year-old boy climbed into Winnicott's jacket and then slit down the pants onto the ground. He repeated this again and again.^[31] Winnicott interpreted this game as a regression and a repeating of birth. He presumed that some babies developed a paranoid attitude by having problems at birth, e.g. in the case of asphyxia.^[32] Also psychosomatic symptoms (headaches, breast- and breathing problems and feelings of getting choked) were interpreted as possible consequences of birth experiences by Winnicott. Nevertheless, he rejected the assumption of a universal birth trauma.

In his book The Search for the Beloved: A Clinical Investigation of the Trauma of Birth and Prenatal Condition of 1949 the British-American psychoanalyst Nandor Fodor (1895–1964) traced certain forms of anxiety back to unprocessed and repressed birth experiences following Rank's assumptions, who had been his psychoanalyst.^[33] Fodor interpreted dreams, experiencing the lack of oxygen, claustrophobia and sexual disorders and their etiology, which he explained by assuming specific pre- and perinatal experiences.

Francis John Mott (1901–1980) was a disciple of Fodor and the first author who concentrated on the placenta as the first object of the fetus.^[34] He wrote, that the fetus fears his placenta as a "blood sucker" or experience it as a "feeder" or "life-giver".^[35] His work an prenatal aspects is connected with his speculative assumptions on a quasi-religious design of the universe.

Material emerging from sessions of psychedelic psychotherapy using LSD and other hallucinogenic drugs was the foundation for research into the enduring effects of pre- and perinatal experiences in adult life conducted by Frank Lake, Athanasios Kafkalides (1919–1989) and Stanislav Grof. Grof went on to formulate an extensive theoretical framework for the analysis of pre- and perinatal experiences, based on the four constructs he called Basic Perinatal Matrices. Lake and Grof independently developed breathing techniques, following Wilhelm Reich (1897–1957) as an alternative to the use of psychedelic drugs, which was subject to considerable legal difficulty from the mid-1960s onwards. A related technique called Rebirthing was developed by psychotherapist Leonard Orr in the 1970s, and Core Process psychotherapy trainees relive presumed birth trauma as part of their training.

The US-American social scientist Lloyd deMause (born 1931) compiled in his essay from 1981 the psychoanalytic approaches to prenatal mental life as well as the physiological findings of the human ontogenesis concerning fetal development. He took several assumptions from the works of Grof and Mott, but left away their metaphysical implications completely. In his own approach he assumes, that the placenta becomes the first object of the fetus, namely in two split versions: a positive and a negative one, he called the "nurturing" and the "poisonous placenta".^[36] DeMause presumed that in every gestation – especially at the end of this period – there are problems of supply with oxygen for the fetus. Because of physiological conditions the placenta would not be able anymore to supply the growing fetus with enough oxygen. This would give rise to states of pain and deprivation. Pre- and perinatal experiences lead to a mental script, a kind of pattern, to which later experiences would be connected with and internalized. He calls the experience of successive good and painful states the "fetal drama", long precursing the well known "oedipal drama" sensu Freud. Besides these theories about prenatal psychology deMause also developed approaches in the field of psychohistory – a system of cultural psychological assumptions, which explain historical processes and phenomenons by using psychological theories. Especially aspects of childhood history and prenatal psychology play an important role.

Fetus at 14 weeks (profile)

In 1992 the Italian child neuropsychiatrist Alessandra Piontelli (born 1945) published a study in her book From Fetus to Child: An Observational and Psychoanalytic Study (1992). Using sonography she examined the behaviour of 11 fetuses. The fetuses showed a very complex behavioural repertoire and were quite different concerning their forms of activities.^[37] They reacted to stimuli in complex ways. Piontelli's study suggested that certain prenatal experiences determined later mental life. Psychological traits, e.g. enhanced oral activity, were recognizable in the prenatal phase, and also after birth. Piontelli interpreted her observations in psychoanalytical terms. Piontelli saw a remarkable continuity between pre- and postnatal mental development. Her study is important, because it combines the assessment of empirical data with the observation of single case studies in the postnatal phase and also in infancy. Her study use equally the methods of academic psychology together with the hermeneutics of psychoanalysis, what makes it unique in the scientific landscape.

Related Research Articles

Psychohistory is an amalgam of psychology, history, and related social sciences and the humanities. Its proponents claim to examine the "why" of history, especially the difference between stated intention and actual behavior. It works to combine the insights of psychology, especially psychoanalysis, with the research methodology of the social sciences and humanities to understand the emotional origin of the behavior of individuals, groups and nations, past and present. Work in the field has been done in the areas of childhood, creativity, dreams, family dynamics, overcoming adversity, personality, political and presidential psychobiography. There are major psychohistorical studies of anthropology, art, ethnology, history, politics and political science, and much else.

<span class="mw-page-title-main">Otto Rank</span> Austrian psychoanalyst (1884–1939)

Otto Rank was an Austrian psychoanalyst, writer, and philosopher. Born in Vienna, he was one of Sigmund Freud's closest colleagues for 20 years, a prolific writer on psychoanalytic themes, editor of the two leading analytic journals of the era, managing director of Freud's publishing house, and a creative theorist and therapist. In 1926, Rank left Vienna for Paris and, for the remainder of his life, led a successful career as a lecturer, writer, and therapist in France and the United States.

<span class="mw-page-title-main">Amniocentesis</span> Sampling of amniotic fluid done mainly to detect fetal chromosomal abnormalities

Amniocentesis is a medical procedure used primarily in the prenatal diagnosis of genetic conditions. It has other uses such as in the assessment of infection and fetal lung maturity. Prenatal diagnostic testing, which includes amniocentesis, is necessary to conclusively diagnose the majority of genetic disorders, with amniocentesis being the gold-standard procedure after 15 weeks' gestation.

Stillbirth is typically defined as fetal death at or after 20 or 28 weeks of pregnancy, depending on the source. It results in a baby born without signs of life. A stillbirth can often result in the feeling of guilt or grief in the mother. The term is in contrast to miscarriage, which is an early pregnancy loss, and sudden infant death syndrome, where the baby dies a short time after being born alive.

Obstetric ultrasonography, or prenatal ultrasound, is the use of medical ultrasonography in pregnancy, in which sound waves are used to create real-time visual images of the developing embryo or fetus in the uterus (womb). The procedure is a standard part of prenatal care in many countries, as it can provide a variety of information about the health of the mother, the timing and progress of the pregnancy, and the health and development of the embryo or fetus.

Twin-to-twin transfusion syndrome (TTTS), also known as feto-fetal transfusion syndrome (FFTS), twin oligohydramnios-polyhydramnios sequence (TOPS) and stuck twin syndrome, is a complication of monochorionic multiple pregnancies in which there is disproportionate blood supply between the fetuses. This leads to unequal levels of amniotic fluid between each fetus and usually leads to death of the undersupplied twin and, without treatment, usually death or a range of birth defects or disabilities for a surviving twin, such as underdeveloped, damaged or missing limbs, digits or organs, especially cerebral palsy.

Dr. Athanassios Kafkalides was a Greek neuropsychiatrist. He was born in 1919 and he died in 1989 while in Athens. He graduated in medicine from the University of Athens and took post-graduate courses in neurology, experimental neurophysiology, neurosurgery and psychiatry at the Prince of Wales General Hospital, the Institute of Neurology in London, the Serafimer Lazarettet and the Karolinska Institutet in Stockholm, and the Eginition Hospital in Athens. From 1960 to 1987 he devoted a great deal of time to clinical research into the field of psychedelic psychotherapy, using drugs such as LSD, psilocybin and ketamine. At the IV World Congress of Psychiatry in Madrid, in 1966, he delivered a paper on the subject of intrauterine life, pioneering the field of pre- and perinatal psychology. He delivered further papers on intrauterine experiences and their repercussions at the VI International Congress of Psychotherapy, the Panhellenic Congress of Psychiatry in Salonica (1972), Athens, and at the Congress of Preventive Psychiatry.

Prenatal development includes the development of the embryo and of the fetus during a viviparous animal's gestation. Prenatal development starts with fertilization, in the germinal stage of embryonic development, and continues in fetal development until birth.

Fetal surgery also known as antenatal surgery, prenatal surgery, is a growing branch of maternal-fetal medicine that covers any of a broad range of surgical techniques that are used to treat congenital abnormalities in fetuses who are still in the pregnant uterus. There are three main types: open fetal surgery, which involves completely opening the uterus to operate on the fetus; minimally invasive fetoscopic surgery, which uses small incisions and is guided by fetoscopy and sonography; and percutaneous fetal therapy, which involves placing a catheter under continuous ultrasound guidance.

Ventriculomegaly is a brain condition that mainly occurs in the fetus when the lateral ventricles become dilated. The most common definition uses a width of the atrium of the lateral ventricle of greater than 10 mm. This occurs in around 1% of pregnancies. When this measurement is between 10 and 15 mm, the ventriculomegaly may be described as mild to moderate. When the measurement is greater than 15mm, the ventriculomegaly may be classified as more severe.

Maternal–fetal medicine (MFM), also known as perinatology, is a branch of medicine that focuses on managing health concerns of the mother and fetus prior to, during, and shortly after pregnancy.

Frank Lake was a British psychiatrist and one of the pioneers of pastoral counselling in the United Kingdom. In 1962, he founded the Clinical Theology Association with the primary aim to make clergy more effective as listeners in understanding and accepting the psychological origins of their parishioners’ personal difficulties. However, the training in pastoral counselling, which he began in 1958, eventually enlisted professional and lay people in various fields from various denominations. Many thousands of people attended the seminars.

Velamentous cord insertion is a complication of pregnancy where the umbilical cord is inserted in the fetal membranes. It is a major cause of antepartum hemorrhage that leads to loss of fetal blood and associated with high perinatal mortality. In normal pregnancies, the umbilical cord inserts into the middle of the placental mass and is completely encased by the amniotic sac. The vessels are hence normally protected by Wharton's jelly, which prevents rupture during pregnancy and labor. In velamentous cord insertion, the vessels of the umbilical cord are improperly inserted in the chorioamniotic membrane, and hence the vessels traverse between the amnion and the chorion towards the placenta. Without Wharton's jelly protecting the vessels, the exposed vessels are susceptible to compression and rupture.

A fetus or foetus is the unborn offspring that develops from a mammal embryo. Following embryonic development, the fetal stage of development takes place. In human prenatal development, fetal development begins from the ninth week after fertilization and continues until the birth of a newborn. Prenatal development is a continuum, with no clear defining feature distinguishing an embryo from a fetus. However, a fetus is characterized by the presence of all the major body organs, though they will not yet be fully developed and functional and some not yet situated in their final anatomical location.

Congenital pulmonary airway malformation (CPAM), formerly known as congenital cystic adenomatoid malformation (CCAM), is a congenital disorder of the lung similar to bronchopulmonary sequestration. In CPAM, usually an entire lobe of lung is replaced by a non-working cystic piece of abnormal lung tissue. This abnormal tissue will never function as normal lung tissue. The underlying cause for CPAM is unknown. It occurs in approximately 1 in every 30,000 pregnancies.

Circumvallate placenta is a rare condition affecting about 1-2% of pregnancies, in which the amnion and chorion fetal membranes essentially "double back" on the fetal side around the edges of the placenta. After delivery, a circumvallate placenta has a thick ring of membranes on its fetal surface. Circumvallate placenta is a placental morphological abnormality associated with increased fetal morbidity and mortality due to the restricted availability of nutrients and oxygen to the developing fetus.

Prenatal memory, also called fetal memory, is important for the development of memory in humans. Many factors can impair fetal memory and its functions, primarily maternal actions. There are multiple techniques available not only to demonstrate the existence of fetal memory but to measure it. Fetal memory is vulnerable to certain diseases so much so that exposure can permanently damage the development of the fetus and even terminate the pregnancy by aborting the fetus. Maternal nutrition and the avoidance of drugs, alcohol and other substances during all nine months of pregnancy is important to the development of the fetus and its memory systems. The use of certain substances can entail long-term permanent effects on the fetus that can carry on throughout their lifespan.

Perinatal matrices or basic perinatal matrices, in pre-perinatal and transpersonal psychology, is a theoretical model of describing the state of awareness before and during birth.

In psychology, limbic imprint refers to the process by which prenatal, perinatal and post-natal experiences imprint upon the limbic system, causing lifelong effects. The term is used to explain how early care of a fetus and newborn is important to lifelong psychological development and has been used as an argument for alternative birthing methods, and against circumcision. Some also refer to the concept as the human emotional map, deep-seated beliefs, and values that are stored in the brain's limbic system. When a fetus or newborn experiences trauma, the brain will register trauma as normal affecting the newborn into adulthood. However, when a fetus or newborn does not experience trauma, the brain will develop healthy coping mechanisms that work effectively into adulthood.

The fetal origins hypothesis proposes that the period of gestation has significant impacts on the developmental health and wellbeing outcomes for an individual ranging from infancy to adulthood. The effects of fetal origin are marked by three characteristics: latency, wherein effects may not be apparent until much later in life; persistency, whereby conditions resulting from a fetal effect continue to exist for a given individual; and genetic programming, which describes the 'switching on' of a specific gene due to prenatal environment. Research in the areas of economics, epidemiology, and epigenetics offer support for the hypothesis.

References

↑ For an overview see: Lloyd DeMause: The fetal origins of history. In: Lloyd deMause: Foundations of Psychohistory.Creative Roots, New York, 1982, p. 244–332; Ludwig Janus: Die Psychoanalyse der vorgeburtlichen Lebenszeit und der Geburt. Centaurus, Pfaffenweiler 1993, S. 1–72; Ralph Frenken: Symbol Plazenta: Die Pränatalpsychologie der Kunst. Springer, Wiesbaden 2015, S. 5–61.
↑ Smotherman, William P.; Robinson, Scott R. (1994). Classical conditioning of opioid activity in the fetal rat. In: Behavioral Neuroscience, 108 (5), S. 951–961.
↑ Otwin Linderkamp, Ludwig Janus, Rupert Linder, Dagmar Beate Skoruppa: Entwicklungsschritte des fetalen Gehirns. In: International Journal of Prenatal and Perinatal Psychology and Medicine. 21(1/2), 2009, (S. 91–105), S. 91. Similarly: Carolin Sheridan Hubert Preissl, Niels Birbaumer: Wie reagiert das fetale Gehirn auf Reize? Untersuchungen mit fetaler Magnetoenzephalographie. In: Karl Heinz Brisch, Theodor Hellbrügge (Hrsg.): Der Säugling: Bindung, Neurobiologie und Gene. Grundlagen für Prävention, Beratung und Therapie. Klett-Cotta, Stuttgart 2008, S. 32.
↑ Otwin Linderkamp, Ludwig Janus, Rupert Linder, Dagmar Beate Skoruppa: Entwicklungsschritte des fetalen Gehirns. In: International Journal of Prenatal and Perinatal Psychology and Medicine. 21(1/2), 2009, S. 99.
↑ Davenport Hooker: The Prenatal Origin of Behavior. University of Kansas Press, Lawrence, Kansas 1952.
↑ Heinz F. R. Prechtl: Wie entwickelt sich das Verhalten vor der Geburt. In: Carsten Niemitz (Hrsg.): Erbe und Umwelt: Zur Natur von Anlage und Selbstbestimmung des Menschen. Suhrkamp, Frankfurt am Main 1987, (S. 141–155), S. 142.
↑ Alessandra Piontelli: From Fetus to Child: An Observational and Psychoanalytic Study. London 1992, S. 28.
↑ Heinz F. R. Prechtl: Wie entwickelt sich das Verhalten vor der Geburt. In: Carsten Niemitz (Hrsg.): Erbe und Umwelt: Zur Natur von Anlage und Selbstbestimmung des Menschen. Suhrkamp, Frankfurt am Main 1987 (S. 141–155), S. 143.
↑ Heinz F. R. Prechtl: Wie entwickelt sich das Verhalten vor der Geburt. In: Carsten Niemitz (Hrsg.): Erbe und Umwelt: Zur Natur von Anlage und Selbstbestimmung des Menschen. Suhrkamp, Frankfurt am Main 1987 (S. 141–155), S. 146; Alessandra Piontelli: From Fetus to Child: An Observational and Psychoanalytic Study. London 1992, S. 32.
↑ Alessandra Piontelli: From Fetus to Child: An Observational and Psychoanalytic Study. London 1992, S. 31.
↑ P. G. Hepper: Fetal memory: Does it exist? What does it do? In: Acta Paeditrica. supplement, 416, 1996, S. 16–20. (S. 17). Spelt repeated these experiments in 1948. G. Hepper: Fetal memory: Does it exist? What does it do? In: Acta Paeditrica. supplement, 416, 1996, S. 16–20 (S. 17).
↑ P. G. Hepper: Fetal memory: Does it exist? What does it do? In: Acta Paeditrica. supplement, 416, 1996, S. 16–20 (S. 17).
↑ See Daniel N. Stern: Die Lebenserfahrung des Säuglings. Klett-Cotta: Stuttgart 1993, S. 65 ff.
↑ J. W. Goldkrand, B. L. Litvack: Demonstration of fetal habituation and patterns of fetal heart rate response to vibroacoustic stimulation in normal and high-risk pregnancies. In: Journal of Perinatology. 11(1), 1991, S. 25–29. (S. 25).
↑ Chantal E. H. Dirix, Jan G. Nijhuis, Gerard Hornstra: Aspects of Fetal Learning and Memory. In: Child Development. 80 (4), 2009, S. 1251–1258.
↑ L. R. Leader, P. Baillie, B. Martin, E. Vermeulen: The assessment and significance of habituation to a repeated stimulus by the human fetus. In: Early Human Development. 7(3), 1982, S. 211–219 (S. 211).
↑ P. G. Hepper: The beginnings of the mind: evidence from the behaviour of the fetus. In: Journal of Reproductive and Infant Psychology. 12, 1994, S. 143–154. (S. 143).
↑ William P. Smotherman, Scott R. Robinson: Classical conditioning of opioid activity in the fetal rat. In: Behavioral Neuroscience. 108 (5), 1994, S. 951–961.
↑ W. Ernest Freud: Remaining in Touch. Gesammelte Schriften 1965–2000. Zur Bedeutung der Kontinuität früher Beziehungserfahrungen. Konsequenzen aus der psychoanalytischen Entwicklungspsychologie für die Prophylaxe früher Schädigungen. Edition Déjà-vu, Frankfurt am Main 2003, ISBN 3-9805317-4-0.
↑ D. K. James, C. J. B. Spencer, B. W. Stepsis: Fetal learning: a prospective randomized controlled study. In: Ultrasound in Obstetrics and Gynecology. 20, 2002, S. 431–438. Richard Ferner Parncutt: Prenatal development. In: G. E. McPherson (Hrsg.): The child as musician. Oxford University Press, 2006, S. 1–31.
↑ Anthony J. DeCasper, William P. Fifer: Of Human Bonding: Newborns Prefer Their Mothers' Voices. In: Science. 208 (4448), 1980, S. 1174–1176.
↑ Overview in: David K. James: Fetal Learning: a Critical Review. In: Infant and Child Development. 19, 2010, S. 45–54.
↑ Ludwig Janus: Die Psychoanalyse der vorgeburtlichen Lebenszeit und der Geburt. Centaurus, Pfaffenweiler 1993, S. 21–75.
↑ Ludwig Janus: Die Psychoanalyse der vorgeburtlichen Lebenszeit und der Geburt. Centaurus, Pfaffenweiler 1993, S. 55.
↑ Robert Kramer: Einsicht und Blindheit: Zur Aktualität von Otto Rank. In: Psyche. 53, 1999, S. 158–200.
↑ Otto Rank: Das Trauma der Geburt und seine Bedeutung für die Psychoanalyse. Fischer, Frankfurt am Main 1988, S. 98.
↑ Otto Rank: Das Trauma der Geburt und seine Bedeutung für die Psychoanalyse. Fischer, Frankfurt am Main 1988, S. 142.
↑ Maret, Stephen (2009), Introduction to Prenatal Psychology, Church Gate Books, p. 16, ISBN 9780578089980
↑ Rank, Otto (1952), The Trauma of Birth, New York: Richard Brunner
↑ Rank, Otto (1932), The Myth of the Birth of the Hero and Other Writings, New York: Random House
↑ Donald W. Winnicott: Birth Memories, Birth Trauma and Anxiety. In: Collected Papers: Through Pediatrics to Psychoanalysis. Routledge, New York 1949, (p. 174–193), S. 177 ff.
↑ Donald W. Winnicott: Birth Memories, Birth Trauma and Anxiety. In: Collected Papers: Through Pediatrics to Psychoanalysis. Routledge, New York 1949, (p. 174–193), p. 185 ff.
↑ Fodor, Nandor (1949), The Search for the Beloved: A Clinical Investigation of the Trauma of Birth and Prenatal Condition, New Hyde Park, NY: University Books
↑ Lloyd DeMause: The fetal origins of history. In: Lloyd deMause: Foundations of Psychohistory.Creative Roots, New York, 1982, p. 249 ff.
↑ Francis J. Mott: The nature of the self. Wingate, London 1959, p. 82 ff; p. 181 f.
↑ DeMause, Lloyd (1982). The fetal origins of history, pp. 258. In: “Foundations of psychohistory.“ New York: Creative Roots. ISBN 0-940508-01-X.
↑ Alessandra Piontelli, From Fetus to Child: An Observational and Psychoanalytic Study, Routledge, London, 1992. See also: Alessandra Piontelli, Luisa Bocconi, Chiara Boschetto, Alessandra Kustermann, Umberto Nicolini, Differences and similarities in the intra-uterine behaviour of monozygotic and dizygotic twins, Twin Research, 1999, 2, S. 264–273 (S. 270 ff.)