Functional Neuroanatomy of Episodic memory (Autobiographical memory)
Gabeza and St Jaques (2007) provided a detailed review of the primary areas of the brain that are involved in AB. As summarized memory creation is dependent upon the retrosplenial cortex, the hippocampus (memory), the occipital lobes (visual component) and cuneus and precunius brain areas so as the amygdala (emotional content of memories). Memory creation, on the other hand is facilitated by the DPC (involved in attentional processes), lateral PFC (involved in organization), and the medial PFC (involved in ‘self-refferal’). (p.116-117). As noted by Loveday and Conway, although the HERA model makes a distinction between the right and the left hemispheric networks for that the former guide in memory retrieval and the latter encoding; the hypothesis of the researchers, based on current findings, is that left hemisphere PFC networks are in fact involved in some aspects of retrieval as well (transient). This hypothesis is related to AB memory on that LH PFC possibly control the choice and amplification of cues that in turn guide posterior network activation (involved in memory storage), whilst the respective RH networks function to stabilize this activation upon memory production (2011).
SenseCam Research Brain Imaging findings
St Jack’s et al (2011), using a stringent methodological design, studied the brain activation patterns of 12 female and 11 male healthy volunteers (age range: 18-35) whilst reviewing SC footage (SC) or being provided with verbal cues (VC) of experienced events. The results demonstrated greater activation (during the SC condition) in the medial temporal lobe of the left hippocampus, left inferior frontal gyrus, retrosplenial cortex and right occipital cortex that corresponded to rating of PM during pictorial footage (SC) with a male gender effect. The results supported that Sensecam activates brain regions important to memory (including hippocampal structures) during memory consolidation/retrieval (p. 39-40). Gabeza and colleagues (2005) have tested SC under real life settings and laboratory conditions and reported greater activation in the medial temporal and prefrontal regions and visual and parahippocampal brain sites, medial prefrontal cortex (that houses processing of self referral), and the hippocampus (that hosts event recollection), a network relating to EM. Moreover, in a second part of the study of Claire, the researchers reported high activation in the occipital areas (involved in visualization) and posterior parietal regions during retrieval. |
Brain Plasticity?
Neuroimaging studies suggest an association of increased memory consolidation (and episodic memory support) to activation of PFC, and hippocampus regions that increases with age. However, in normal ageing, or sustained brain damage memory- related brain structures or their associated circuits may become dysfunctional, with episodic memory being more susceptible to damage. Based on the principle of brain plasticity, SC might be able to strengthen those circuits (and benefit memory capacities) via ‘training’ and strengthening the synapses. Moreover, prolonged stress is associated to increased cortisol secretion (being highly toxic to and being able to damage the hippocampus) that can negatively impact on neurogenesis and interfere with BDNF growth factors. As research shows SC also reduces anxiety levels |