as defense mechanisms that individual uses to keep themselves safe from negative consequences. despite purposefully repressing these memories, freud believed they still affect the individual unconsciously and, in some cases, will be brought back into one's recollection. since freud’s original conception of repression, much has changed and been debated across the field of psychology. in the eyes of critics of repressed memory, it is synonymous with false memory; however its proponents will argue that these people truly did have traumatic experiences. repressed memories and the impact of childhood trauma on memory are significant to note, as childhood sexual assault prosecutions may take place years after an alleged sexual assault. maltreatment causes impairments or distortions in cognitive, emotional processes, neurobiology, and brain development which might affect memory. repressed memories of interpersonal violence during childhood have been explored in longitudinal research. findings suggest that adults’ ability to recall from long-term memory instances of childhood maltreatment depends on numerous factors. factors include individual differences and development, the overall impact of the traumatic experience, and the modality interviewers use to assess adult childhood trauma. for example, the more significant the impact of childhood maltreatment is, the more accurate adult long-term memory of the events recall may be. additional predictors of long-term memory of child maltreatment are the form of abuse and the age of onset. research shows that being older when traumatic events occur correlates with a more accurate memory. intrusive thoughts main article: intrusive thoughts intrusive thoughts are defined as unwelcome, involuntary thoughts, images or unpleasant ideas that may become obsessions, are upsetting or distressing, and can be difficult to be free of and manage. in patients who have suffered from traumatic events, especially those with post-traumatic stress disorder, depression or obsessive-compulsive disorder, the thoughts are not as easy to ignore and can become troubling and severe. these thoughts are not typically acted on; the obsession of the thoughts usually comes from intense guilt, shame or anxiety relating to the fact that the patient is having the thoughts to begin with, so they are unlikely to actually act on things they feel so badly about. in trauma patients, the intrusive thoughts are typically memories from traumatic experiences that come at unexpected and unwanted times. the primary difference from other intrusive thoughts for patients is that the memories are real rather than imagined. emotion emotion is a large part of trauma, especially near death experiences. the effect emotions have on memory in different instances is an integral part of the effect of trauma on memory. emotional events tend to be recalled with more frequency and clarity than memories not associated with extreme emotions. typically traumatic events, such as physical attack or sexual abuse, are interrelated with strong negative emotions, causing these memories to be very strong and more easily recalled than memories not associated with similar emotions, or even those connected to positive emotions. emotion's strong connection with memory also has to do with how much attention or focus an individual has on the event. if they are heavily emotionally involved in the event, a lot of their attention is directed at what's happening, rendering it a stronger memory. it is also the case with emotionally aroused situations that even if attention is limited, it is more likely that a memory associated with the strong emotion will remain as opposed to some neutral stimulus. this increase in attention and encoding is due to the activation of the prefrontal-hippocampal-amygdala complex and results in improvement in later memories. chemically, this is because the emotional and physical stress caused by traumatic events creates an almost identical stimulation in the brain to the physiological condition that heightens memory retention. it excites the neuron-chemical activity centers of the brain that affects memory encoding and recollection. this reaction has been enforced by evolution as learning from high-stress environments is necessary in "fight or flight" decisions that characterize human survival. implications in neuropsychological testing and treatment it is common to see mild and subtle neurocognitive deficits in adults with ptsd across differing trauma types. research typically breaks down the assessment of neurocognitive function into nine cognitive domains. these domains include attention/working memory, executive functions, verbal learning, verbal memory, visual learning, visual memory, language, speed of information processing, and visuospatial abilities. one study highlights the discrepancy in sustained attention, working memory, and verbal memory among veterans with ptsd compared to the neurotypical control group. verbal and visual memory verbal memory is a recollection of verbally presented information. several neuropsychological assessments can be administered to assess verbal memory, such as the boston naming test (bnt), california verbal learning test (cvlt), and the logical memory ii subtest of the wechsler memory scale-iii (wms-iii). neuropsychological assessments for verbal memory typically include learning a list of words or a story and then performing recall. performance on assessments of verbal memory demonstrates an individual’s ability to encode said material in memory. by comparison, visual memory is recalling what has been observed or seen. it is typical for visual memory to remain intact, while verbal memory does not. this may explain why verbal trauma narratives are often disorganized, incoherent, or fragmented. while completing declarative verbal memory tasks, some individuals with ptsd illustrated anterograde memory difficulties and low encoding and storage. research findings suggest this may be due to complications from ptsd symptoms, which may result from reduced left hippocampal gray matter density. research suggests that this could have significant implications for an individual with ptsd’s responsiveness to cognitive behavioral therapy because verbal memory impairment may impact spoken or written recall of trauma memories. attention and working memory in response to cognitive tasks, neuroimaging supports the notion that individuals with ptsd evoke a hypoactive response in both attention and working memory. mri results have shown significantly reduced gray matter density clusters in the anterior cingulate cortex, ventromedial prefrontal cortex, and left hippocampus. this area of the brain is typically involved in fear processing, emotion regulation, memory encoding, and retrieval; as such, damage to this area of the brain can lead to functional discrepancies. these brain structures support cognitive constructs such as attentional switching, information processing speed, and working memory. hypervigilance is a commonly experienced symptom of ptsd, which indicates a dysfunction in attention processing manifested as a high-attention-bias toward possible environmental threats that is distracting or otherwise problematic in an individual’s day to day life. post-traumatic stress disorder main article: posttraumatic stress disorder post-traumatic stress disorder is a psychological disorder (in the same category as: reactive attachment disorder, disinhibited social engagement disorder, acute stress disorder and adjustment disorders) caused by exposure to a terrifying event or ordeal involving the occurrence or threat of physical harm or where a person learns these terrible events happened to a close family member or someone whom they care about. it is one of the most severe and well-known of the different types of psychological trauma, mostly due to its prevalence in war veterans. it can manifest itself as early as after the first year of life. typically symptoms include avoidance of reminders of the traumatic event or mention thereof, irritability, trouble sleeping, emotional numbness and exaggerated reactions to surprises. one of the most common and powerful symptoms, is the recurrence of random intense memories from the event (intrusive thoughts). this can manifest itself in different ways such as flashbacks of the event and unwanted thoughts about the trauma (e.g. "why did this happen to me?"). ptsd patients who have gone through different traumatic experiences will have small variances in their symptoms, mostly insignificant. for example, ptsd patients who were rape victims will have aversion to words such as touch and dirty while patients who were in a fire or war experience will respond similarly to words like burn or fight. the stress of ptsd can have an adverse effect on memory. specifically, this can have severe effects on the hippocampus, including decrease in hippocampus volume, causing problems with transferring short-term to long-term memory, and with the formation of short-term memories. to expand on the relationship between ptsd and hippocampal volume, one meta-analysis found that individuals diagnosed with ptsd have significantly smaller hippocampi volumes compared to controls. another meta-analysis found that in adults who experienced childhood trauma, the hippocampi were smaller than control hippocampi. in a broad overview, individuals with ptsd who have impairments to their memory generally have this impairment in their verbal memory, more so than their visual memory. though studies show that there is no singular way in which patients' memories are affected by ptsd, north korean refugees with ptsd were found to have generally lower scores on memory tests than control groups of refugees without ptsd. the early presentation of memory impairment compared to complications with other cognitive functions may be due to dysfunction in the hippocampus. world war ii (wwii) contributed to an abundance of ptsd cases today. many of the patients diagnosed with pstd after wwii did not have memories of the traumatic events yet had symptoms like hysteria. the amnesia can be attributed to freud’s theory of repression which suggests that individuals repress their memories to keep themselves safe from further harm/consequences. stricker et al. (2017) furthered this idea through research that demonstrated higher rates of cognitive impairment (e.g., executive functioning, attention, working memory, and processing speed) in individuals diagnosed with ptsd, like service members or veterans. memory and learning ability were the most affected areas. more specifically, veterans had a more difficult time with initial learning and encoding the information than recalling it at a later time. moradi et al. (1999) attributes the memory loss associated with ptsd to "intrusion, avoidance, and hyperarousal symptoms." these symptoms are thought to interrupt performance memory. additionally, the loss of memory was attributed to a smaller hippocampus in those with ptsd, as the hippocampus is responsible for memory functioning. effects of memory impairment on ptsd treatment response memory is a vital predictive factor in a positive response to cognitive behavioral therapy for individuals with a trauma history. specifically, the more intact their verbal memory functioning, the greater the positive predictive outcomes are for treatment response. additionally, treatment impacts highlight the bidirectional relationship between neurocognitive functioning and trauma symptom preservation. several studies have associated improved ptsd symptoms with receiving a treatment that enhances cognitive inhibition. some research supports emdr and brief eclectic therapy as possible treatment modalities that can intercede verbal memory, processing speed, and executive functioning in individuals with ptsd symptoms. memory performance improves alongside a reduction in ptsd symptoms, which indicates that some effects of ptsd on memory may be reversible upon symptom improvement. for example, patients who exhibited a positive treatment response showed improved verbal memory and increased hippocampal volume.