In presence of a person suffering of a borderline disorder, it is possible to think that this person is a "professional liar" or pathological.  The truth is, of course, much more complex beyond often misleading appearances.  Clinical studies, although very interesting not bring THE answer and you will find on the last part of this document our vision which we hope more comprehensive and listening to their suffering

Glossary

Overgeneral memory : This refers to the tendency for a depressed, when asked to retrieve memories of a specific event that occurred at a particular time and place, to retrieve more generic personal memories referring to repeated experiences or wholeperiods in their lives (Brittlebank AD, Scott J, Williams JM, Ferrier IN, “Autobiographical memory in depression: state or trait marker?”, Br J Psychiatry. 1993)
.
Autobiographical Memory : Memory for events and issues related to yourself , includes memories for specific experiences and memory for the personal facts of one’s life
Remembering buying your first car --> specific experience
“Do you own a car?” --> personal fact
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Affect - The emotional tone characteristic of each person's presentation. Affect is depressed in dysthymia, elevated in manic phases

* Arntz A, Meeren M, Wessel I. - Dept. of Medical, Clinical and Experimental Psychology, Maastricht, The Netherlands
2OO2 Behav Res Ther - No evidence for overgeneral memories in borderline personality disorder.
"Borderline personality disorder, anxiety disorders and childhood traumas were not related to number of specific memories"

* Jones B, Heard H, Startup M, Swales ... Department of Psychology, Bath Mental Health NHS Trust.
1999 Psychol Med - Autobiographical memory and dissociation in borderline personality disorder.
23 patients with BPD and 23 matched controls
"Patients with BPD have difficulties in recalling specific autobiographical memories. These difficulties are related to their tendency to dissociate and may help them to avoid episodic information that would evoke acutely negative affect"

* Startup M, Heard H, Swales M, Jones B,... - School of Psychology, University of Wales, Bangor, UK.
2001 Br J Clin Psychol - Autobiographical memory and parasuicide in borderline personality disorder.
"Over-general,autobiographical recall may help to protect borderline individuals from parasuicidal acts by helping them to avoid distressing memories."

* Torgersen S, Alnaes R. - Department of Psychology, University of Oslo, Norway.
1992 Compr Psychiatry - Differential perception of parental bonding in schizotypal and borderline personality disorder patients.
54 patients with schizotypal and/or borderline personality disorders. Perception of parental behavior in childhood. "Both schizotypals and borderlines reported low care; however, schizotypals remembered underprotection and borderline remembered overprotection. The study suggests parental negative over-involvement for borderlines"

* Williams LM. - Family Research Laboratory, University of New Hampshire, Durham
1994 J Consult Clin Psychol - Recall of childhood trauma: study of women's memories of child sexual abuse.
129 women with histories of sexual victimization in childhood
A large proportion of the women (38%) did not recall the abuse that had been reported 17 years earlier. Women who were younger at the time of the abuse and those who were molested by someone they knew were more likely to have no recall of the abuse.

* O'Leary KM, Brouwers P, Gardner DL, Cowdry RW. - Div of Intramural Research Programs, NIMH, Neuroscience Center at St. Elizabeths, Washington, DC
1991 - Am J Psychiatry 1991 - Neuropsychological testing of patients with borderline personality disorder.
16 DSM IIIR bpd patients and 16 normal volunteers
RESULTS: The performance of the borderline patients was significantly impaired in comparison with that of the normal group on memory tests requiring uncued recall of complex, recently learned material. The patients' performance was also significantly impaired on several visual perceptual tests. CONCLUSIONS: The observed difficulties in separating essential from extraneous visual information and in recalling complex material may be relevant in understanding some of the clinical features of borderline personality disorder.

* Paris J. - Department of Psychiatry, McGill University, Montreal, Quebec, Canada.
1995 Harv Rev Psychiatry - Memories of abuse in borderline patients: true or false ?
This review will examine issues related to the validity of memories of child abuse in patients with borderline personality disorder (BPD). A large body of research has shown that all memories are distorted by cognitive schema, and that "recovered memories" may be particularly unreliable. Evidence will be examined suggesting that borderline patients have a distorted perception of interpersonal events.

* Epstein MA, Bottoms BL - La Rabida Children's Hospital, Chicago, Illinois, USA.
2OO2 Child Maltreat - Explaining the forgetting and recovery of abuse and trauma memories: possible mechanisms
"Rates of forgetting were similar among victims who experienced sexual abuse, physical abuse, and multiple types of traumas. Victims of other types of childhood traumas (e.g., car accidents) reported less forgetting than victims of childhood sexual abuse or multiple types of trauma. Most victims' characterizations of their forgetting experiences were not indicative of repression in the classic Freudian sense but instead suggested other more common mechanisms, such as directed forgetting and relabeling."

* Snyder S.
1986 Am J Psychiatry - Pseudologia fantastica in the borderline patient.
"An infrequently described clinical feature sometimes associated with borderline personality disorder is pseudologia fantastica, or pathological lying"

Memory, vision, lies, when, how ?

"History of losing time. For example, patients with borderline personality disorder might start watching a movie and suddenly reorient later in the middle of another movie with no clear memory of the elapsed time" (Richard J. Laban, Ph.D ,”Working with the Borderline Personality Disordered Client”, CAAP Connection 1998)

"During a dissociative,episode, the brain is thought to switch into a biochemically-induced "high defense mode", during which the storage of new memories is effectively blocked. Yet not all memory is erased, which is quite confusing to those interacting with the individual during these times. Researchers propose that "these early encoding deficits [...] have a deleterious effect on the short-term memory system; they manifest as deficits in the ability to take in new information but not in the ability to conceptualize and manipulate previously encoded information" (Helen, “Memory, Trauma & BPD”, Helen's World of BPD Resources)

* Cyril Jeckel - Interne en DES Psychiatrie au CHU de Reims.
2OO2 revue Forensic N°9.
"...L'existence de mensonge pathologique, de « pseudologia fantastica » chez certains sujets borderlines peut conduire à de fausses accusations. Elles peuvent être dirigées contre leur thérapeute [Gutheil Am J Psychiatry, 1989 ]... Le manque de tolérance à l’angoisse peut également expliquer ces mensonges pathologiques, le sujet préférant mentir plutôt que de souffrir des conséquences d’une réponse fidèle à la réalité. Les fausses accusations les plus fréquentes sont les fausses accusations de viol [Snyder Am J Psychiatry, 1986 ].
De même, certaines femmes qui portent plainte de façon abusive pour harcèlement sexuel sont en fait essentiellement motivées par le désir de se dépeindre eux-mêmes comme victime...Il s’agit souvent de sujets souffrant d’un trouble borderline [Feldman-Schorrig - Factitious sexual harassment. Bull Am Acad Psychiatry Law, 1996]

Aapel view of lying, memory loss, visual impairment and borderline personality disorder

Here is our feeling.
Some evidence says that Borderline patient have memory problems but also visual impairment
Trauma and memory are directly connected. "Forgetting" events is a defense mode

Could we say that borderline peoples are liars ?

yes, we all are liars, borderline and not borderline peoples.

Why are they lying ?

To protect themselves, and certainly because WE (the "non") are too stupid to understand him. In that way when we ask him "are you ok", it is difficult to him to say "no" and explain why

Are they pathological liars ?

No, very often the patient is conscious about his lie. He has the possibility to lie or not. If it was a pathological liar, he would be unable to stop lying, it will be a chronic lying
(we suppose that it is possible to have both BPD and pathological lying)

Are they conscious of their lies ?

Very often, yes and sometimes no
In that case, for them it is not a lie, but, in real, it is not the truth

When are they lying without knowing that ?

Each time, we ask them to give us an information wrongly stored in their memory.
Trauma, dissociation, lying and memory are linked
During their transient epidose of dissociation, their memory storage is impaired
Dissociation is a self-defensive mode to escape from unacceptable situation. In that way it is logical to not memorize exactly such episode.
In such circonstance asking a patient about this fact will lead him to say HIS truth, but it is a lie. (It is then very dangerous and can lead to false accusations)

What about their ability to erase the "good" side of some people ?

Our hypothesis, theory (unproved as we think) about the "black and white thinking" is linked with overgeneral memory
Like in PTSD, a borderline is not living some event about the present but about the past.
If your trauma was a rape in an elevator. Each time you will enter in an elevator you will not live the present as just entering in the elevator but in the past, remembering the rape.
So when you asked a BPD patient to remember when he had a "gool meal with michael" which is now the new "all bad michael", the information is hidden.
Why ?
The self defensive mechanism (trauma - black and white thinking we assume) has recorded the new trauma information "michael and argument" above the previous one "michael and meal", and not beside the information.
It is a top priority data (like "rape" is a top priority data linked with "elavator")
So when we ask a specific information about "meal and michael", the overgeneral memory of the borderline will find the data "michael (and argument)" and not "michael and meal", "michael and funfair", "michael and broken led", etc...
But now, the information "michael" became a traumatic thinking like the elevator sample.
It is now "michael and argument", so each time you talk about "michael" to the patient, the only thinking is the "trauma event - michael and argument", unacceptable for a borderline.
And if there is no way for the patient to physically escape from the "trauma thinking" situation (the "elevator"), the solutions are "rage attack", "panic attack", ... or "dissociation"
All this is certainly the inability for BPD people to manage "stress" and "trauma"
- not sure to explain well -

What do you think about visual impairment and borderline disorder ?

The study of O'Leary give some evidence about this. It seems totaly logical when we think that BPD people are emotionaly driven.  In that way the essential visual information are not defined by "reason" but by "emotion". The same scene lived by a bpd people will not be "seen" the same way if the person is for example euphoric or in panic attack