Silent Recall Research Articles

Neural correlates of recalled sadness, joy, and fear states: a source reconstruction EEG study.

The capacity to understand the others' emotional states, particularly if negative (e.g. sadness or fear), underpins the empathic and social brain. Patients who cannot express their emotional states experience social isolation and loneliness, exacerbating distress. We investigated the feasibility of detecting non-invasive scalp-recorded electrophysiological signals that correspond to recalled emotional states of sadness, fear, and joy for potential classification. The neural activation patterns of 20 healthy and right-handed participants were studied using an electrophysiological technique. Analyses were focused on the N400 component of Event-related potentials (ERPs) recorded during silent recall of subjective emotional states; Standardized weighted Low-resolution Electro-magnetic Tomography (swLORETA) was employed for source reconstruction. The study classified individual patterns of brain activation linked to the recollection of three distinct emotional states into seven regions of interest (ROIs). Statistical analysis (ANOVA) of the individual magnitude values revealed the existence of a common emotional circuit, as well as distinct brain areas that were specifically active during recalled sad, happy and fearful states. In particular, the right temporal and left superior frontal areas were more active for sadness, the left limbic region for fear, and the right orbitofrontal cortex for happy affective states. In conclusion, this study successfully demonstrated the feasibility of detecting scalp-recorded electrophysiological signals corresponding to internal and subjective affective states. These findings contribute to our understanding of the emotional brain, and have potential applications for future BCI classification and identification of emotional states in LIS patients who may be unable to express their emotions, thus helping to alleviate social isolation and sense of loneliness.

A consensus-based elastic matching algorithm for mapping recall fixations onto encoding fixations in the looking-at-nothing paradigm

We present an algorithmic method for aligning recall fixations with encoding fixations, to be used in looking-at-nothing paradigms that either record recall eye movements during silence or want to speed up data analysis with recordings of recall data during speech. The algorithm utilizes a novel consensus-based elastic matching algorithm to estimate which encoding fixations correspond to later recall fixations. This is not a scanpath comparison method, as fixation sequence order is ignored and only position configurations are used. The algorithm has three internal parameters and is reasonable stable over a wide range of parameter values. We then evaluate the performance of our algorithm by investigating whether the recalled objects identified by the algorithm correspond with independent assessments of what objects in the image are marked as subjectively important. Our results show that the mapped recall fixations align well with important regions of the images. This result is exemplified in four groups of use cases: to investigate the roles of low-level visual features, faces, signs and text, and people of different sizes, in recall of encoded scenes. The plots from these examples corroborate the finding that the algorithm aligns recall fixations with the most likely important regions in the images. Examples also illustrate how the algorithm can differentiate between image objects that have been fixated during silent recall vs those objects that have not been visually attended, even though they were fixated during encoding.

Effectiveness of Reminiscence Therapy on Reduction of Stress among Elderly Residing in old age Home

Reminiscence has been defined as the “vocal or silent recall of events in a person's life, either alone or group of people”. Reminiscence therapy is a process in which individual attempt to accept negative event in the past, resolve past conflicts, reconcile the discrepancy between ideals and reality, identify continuity between past and present, and find meaning and worth in life. It helps the elderly recollect past coping activity and strategies, including memories of plans as developed to solve difficult situation, goal directed activities and the achievement of one's own goal or goals one helped other meet. Pre-experimental approach was adopted to determine the effectiveness of reminiscence therapy among elderly residing in Red Cross society old age home sector-15 Panchkula. One group pre-test post-test research design was used where 30 old age people were included in pre-experimental one group respectively. Convenient sampling technique was used to select 30 elderly people residing in old age home. Protocol for Reminiscence therapy was developed and content validity was determined by experts internal consistency (r=0.7) and stability (r=0.98) of tool was tested by using split half reliability test-re test method respectively. Pilot study was conducted found to be feasible. Base line stress level was assessed and reminiscence therapy was introduced where seven sessions were delivered for subject in experimental group. It is evident from the result that pretest mean score was founded to be 20.06 as compared to the post test mean score 11.1. Hence the study concluded that the reduction of stress level among elderly people after the administration of reminiscence therapy. This indicate that the reminiscence therapy was effective therefore the null hypothesis is rejected.

On the electrophysiology of effective visual memory as measured by QEEG

An investigation into the QEEG parameters of effective cognitive functioning of visual memory for six Korean figures was conducted employing 69 normal subjects. Subjects studied the figures for 1 minute, engaged in an immediate 30-second quiet recall period, which was then followed by the subjects drawing the figures. A delayed recall of 45 minutes later followed the same methodology. The recall performances were correlated with the QEEG variables. For the input stage, total memory was determined predominantly by specific patterns of left frontal (F7, F3, Fpl) projections (phase and coherence activity) and left central/posterior (T3, C3, P3) phase (Alpha and Betal( 13–32 Hz)) projections. Success during immediate silent recall was determined by left frontal (F7, Fpl, F3) projections and left central/posterior (T3, T5, Ol, P3) projections in the Beta frequencies. Long term-delayed recall was determined by Ol coherence Alpha projection activity and Symmetry of Beta2 (32–64 Hz) at F8. Degree of activation variables (from visual attention and eyes closed) showed different patterns of successful activations.

The cerebellum plays a role in conscious episodic memory retrieval

The cerebellum has traditionally been considered to be primarily dedicated to motor functions. Its phylogenetic development and connectivity suggest, however, that it also may play a role in cognitive processes in the human brain. In order to examine a potential cognitive role for the cerebellum in human beings, a positron emission tomography (PET) study was conducted during a "pure thought experiment": subjects intentionally recalled a specific past personal experience (consciously retrieved episodic memory). Since there was no motor or sensory input or output, the design eliminated the possibility that cerebellar changes in blood flow were due to motor activity. During silent recall of a consciously retrieved episodic memory, activations were observed in the right lateral cerebellum, left medial dorsal thalamus, medial and left orbital frontal cortex, anterior cingulate, and a left parietal region. These activations confirm a cognitive role for the cerebellum, which may participate in an interactive cortical-cerebellar network that initiates and monitors the conscious retrieval of episodic memory.

The cerebellum plays a role in conscious episodic memory retrieval

The cerebellum has traditionally been considered to be primarily dedicated to motor functions. Its phylogenetic development and connectivity suggest, however, that it also may play a role in cognitive processes in the human brain. In order to examine a potential cognitive role for the cerebellum in human beings, a positron emission tomography (PET) study was conducted during a “pure thought experiment”: subjects intentionally recalled a specific past personal experience (consciously retrieved episodic memory). Since there was no motor or sensory input or output, the design eliminated the possibility that cerebellar changes in blood flow were due to motor activity. During silent recall of a consciously retrieved episodic memory, activations were observed in the right lateral cerebellum, left medial dorsal thalamus, medial and left orbital frontal cortex, anterior cingulate, and a left parietal region. These activations confirm a cognitive role for the cerebellum, which may participate in an interactive cortical-cerebellar network that initiates and monitors the conscious retrieval of episodic memory. Hum. Brain Mapping 8:226–234, 1999. © 1999 Wiley-Liss, Inc.